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In a recent paper (2019 Phys. Rev. A 99 , 053617), the total number of fermion pairs in a spin-balanced two-component Fermi gas of 6Li atoms was experimentally probed in the normal phase above the superfluid critical temperature, in order to investigate the sectors of pseudogap and preformed-pair in the temperature–coupling phase diagram. Here, we present a theoretical account of these experimental results in terms of an ab initio self-consistent t-matrix calculation, which emphasizes the role of the pair-correlation function between opposite-spin fermions at equilibrium. Good agreement is found between the available experimental data and the theoretical results obtained with no adjustable parameter. [ABSTRACT FROM AUTHOR]

Shape optimization in unsteady flow problems enables the consideration of dynamic effects on design. The ability to treat unsteady effects is attractive, as it can provide performance gains when compared to steady-state design methods for a variety of applications in which time-varying flows are of paramount importance. This is the case, for example, in turbomachinery or rotorcraft design. Given the high computational cost involved in time-accurate design problems, adjoint-based shape optimization is a promising option. However, efficient sensitivity analysis should also be accompanied by a significant decrease in computational cost for the primal flow solution, as well. Reduced-order models, like those based on the harmonic balance concept, in combination with the calculation of gradients via adjoint methods, are proposed for the efficient solution of a certain class of aerodynamics optimization problems. The harmonic balance method is applicable if the flow is characterized by discrete finite dominant flow frequencies that do not need to be integer multiples of a fundamental harmonic. A fully-turbulent harmonic balance discrete adjoint formulation based on a duality-preserving approach is proposed. The method is implemented by leveraging algorithmic differentiation and is applied to two test cases: the constrained shape optimization of both a pitching airfoil and a turbine cascade. A key advantage of the current approach is the accurate computation of gradients as compared to second order finite differences without any approximation in the linearization of the turbulent viscosity. The shape optimization results show significant improvements for the selected time-dependent objective functions, demonstrating that design problems involving almost-periodic unsteady flows can be tackled with manageable computational effort. [ABSTRACT FROM AUTHOR]

An investigation on non-equilibrium condensing steam flow is conducted to attain a semi-analytical model for the prediction of the Wilson point up to the critical point. The database for the analysis includes experimental observations in various nozzles and conditions (ranging from 20 to 150 bar) taken from the literature as well as additional data at lower and higher reduced pressures, generated by means of a calibrated quasi-1D model based on the method of moments. The simplified model is based on a reformulation of the Wilson point in terms of activation time, defined as the temporal interval between the instant at which the flow is at saturation conditions and the inception stable of condensation. This allows to incorporate the dependency of the Wilson point on the cooling rate and dew-point temperature, which are found the key parameters affecting the delay of condensation. The accuracy of the approach is proved by predicting the degree of subcooling on four different test cases, with deviations against experiments in the range of 1 − 10 % . As demonstrated, the same approach can be exploited to design nozzles free of condensation. [ABSTRACT FROM AUTHOR]

Examines the ground state configuration and the spin-wave excitations of a model of two ferromagnetic monolayers using a microscopic and quantum approach. Formulation of the spin-wave theory; Results; Discussion.

Presents a study which analyzed an experimental data showing a dimensional crossover of the T-dependent magnetization in molecular beam epitaxy-grown iron(110)/silver (Ag)(111) superlattices with different Ag spacer thickness. Role of surface anisotropies in the stabilization of the long range order; Spin-wave dispersion curves and magnetization; Asymptotic forms for the temperature dependence of the spin deviation in the quasi-two dimension regime and in the three dimension.

An adjoint-based shape optimization approach for supersonic turbine cascades is proposed for application to organic Rankine cycle (ORC) turbines. The algorithm is based on an inviscid discrete adjoint method and encompasses a fast look-up table (LuT) approach to accurately deal with real-gas flows. The turbine geometry is defined by adopting state-of-the-art parameterization techniques (NURBS), enabling to handle both global and local control of the shape of interest. A preconditioned steepest descent method has been chosen as gradient-based optimization algorithm to efficiently search for the nearest minimum. The potential of the optimization approach is first verified by application on the redesign of an existing converging-diverging turbine nozzle operating in thermodynamic regions characterized by relevant real-gas effects. A significant efficiency improvement and a more uniform flow at the blade outlet section are achieved, with expected beneficial effects on the aerodynamics of the downstream rotor. The optimized configuration is also assessed by means of high-fidelity turbulent simulations, which point out the capability of the present inviscid approach in optimizing supersonic turbine cascades with very limited computational burdens. Finally, the newly developed real-gas adjoint method is compared against adjoints based on ideal equations of state on the same design problem. Results show that the performance gain obtained by a fully real-gas optimization strategy is by far higher than that achieved with simplified approaches in case of ORC turbines. This proves the relevance of including accurate thermodynamic models in all steps of ORC turbine design. [ABSTRACT FROM AUTHOR]

Abstract: Sexuality and affectivity constitute a complex phenomenon involving many spheres: biological, psychological and social. To investigate these aspects, we distributed a dedicated questionnaire, followed by an interview, to 130 elderly residents in Milan and 100 in Monza. The answers indicated that the elderly communicate their emotions regarding the affective and sexual sphere, with different levels of desire for physical contact. The main variables were sex, age, marital status, co-morbidity and poly-pharmacotherapy, the perception of health status and of oneself, past experiences, cultural conditioning and social factors. [Copyright &y& Elsevier]

The mechanical response of the bovine periodontal ligament (PDL) subjected to uniaxial tension and compression is reported. Several sections normal to the longitudinal axis of bovine incisors and molars were extracted from different depths. Specimens with dimensions 10×5×2 mm including dentine, PDL and alveolar bone were obtained from these sections. Scanning electron microscopy suggested a strong similarity between the bovine PDL and the human PDL microstructure described in the literature. The prepared specimens were tested in a custom made uniaxial testing machine. They were clamped on their bone and dentine extremities and immersed in a saline solution at 37°C. Stress–strain curves indicated that the PDL is characterized by a non-linear and time-dependent mechanical behaviour with the typical features of collagenous soft tissues. The curves exhibited hysteresis and preconditioning effects. The mechanical parameters evaluated in tension were maximum tangent modulus, strength, maximizer strain and strain energy density. For the molars, all these parameters increased with depth except for the apical region. For the incisors, all parameters increased with depth except ultimate strain which decreased. It was assumed that collagen fibre density and orientation were responsible for these findings. [Copyright &y& Elsevier]

The study examined the relationships among dissociative experiences, anger proneness, and attachment styles in late adolescent females. One hundred sixty-two college students (mean age = 17.5 years) were assessed using the Dissociative Experience Scale (DES), the State-Trait Anger Expression Inventory (STAXI), and the Adult Attachment Questionnaire (AAQ), a self-report tool for assessing attachment styles (avoidant, secure, and ambivalent-resistant) in close relationships of youths and adults. Significant correlations were obtained between DES scores (total and factorial) and STAXI scores (State Anger, Trait Anger, Anger/In, and Anger/Expression), confirming in a nonclinical sample the connection between anger proneness and dissociation described in patients with dissociative disorders. Insecure females, particularly ambivalent ones, scored higher on the DES, supporting van der Kolk's hypothesis of an inverse relationship between secure attachment and dissociative tendency. Moreover, insecurely attached females showed more anger proneness, with some differences between ambivalent and avoidant types. Further research should be conducted to examine these relationships in males, as well as to clarify the role of insecure attachment in anger management and the recourse to dissociation in late adolescence as a protective response to trauma and emotional distress. [ABSTRACT FROM AUTHOR]

Alternating gradient force magnetometry and Brillouin light scattering (BLS) experiments were exploited to investigate the perpendicular magnetic anisotropy (PMA) localized at the CoFeB–MgO interface, both in Ta/CoFeB/MgO heterostructures (bottom samples) and in the inverted ones MgO/CoFeB/Ta (top samples). Thermal treatment was found to induce a marked increase of the PMA with respect to the as grown state. Using linear spin wave theory, an analysis of the spin wave frequencies was performed which allowed to estimate the thickness dependence of the PMA in the single CoFeB film. Magnetic tunnel junctions with the Ta/CoFeB/MgO/CoFeB/Ta structure were also studied by BLS. The analysis of the experimental results, performed via the linear spin wave theory, revealed that there is an antiferromagnetic interlayer exchange coupling between the free and the fixed CoFeB layers which increases after the annealing procedure. [ABSTRACT FROM AUTHOR]

An abstract of the article "Unfractionated Heparin for Venous Thromboembolism Prevention in the Hospitalized Medical Patient: Should Dosing be Once, Twice, or thrice Daily?," by C.E. Mahan, M. Pini and A.C. Spyropoulos is presented.

An abstract of the article "Heparins and Bleeding Complications: Size of the Problem and Risk Determinants," by M. Pini, C. Pattacini and D. Dazzi is presented.

The effect of graded anisotropy on static and dynamic magnetic properties of Ar+-irradiated FePt films has been investigated by static magnetometry, magnetic force microscopy, and Brillouin light scattering from thermally excited spin waves. A gradual variation of magnetic anisotropy with film thickness was obtained by Ar+ irradiation. The irradiation incidence angle influences the anisotropy profile: on decreasing α, a decreasing thickness of the hard L10 phase and an increasing thickness of the soft A1 phase were obtained. Accordingly, the zero-field spin-wave frequency gap was found to decrease. In the sample with the highest soft-phase thickness the spin-wave frequency gap takes a substantial value (ν0≈6 GHz), which could be reproduced assuming the presence of a nonzero "rotatable" anisotropy (i.e., any direction in the film plane can be established as the easy axis by the application of a saturating magnetic field along this direction). The hypothesis is supported by both magnetometry and magnetic force microscopy data. [ABSTRACT FROM AUTHOR]

In this study a new multipath mitigation architecture for satellite navigation receiver, named coupled amplitude delay lock loops (CADLLs) is presented. This architecture exploits the 'turbo principle' to separately track the line-of-sight (LOS) signal and multipath signals in order to mitigate the effects of the multiple reflections. The delay lock loop (DLL) and the amplitude lock loop (ALL) are two basic elements in the structure. DLL is in charge of estimating and tracking the code delay of a specific ray in the incoming signal while ALL is in charge of estimating the corresponding amplitude. A pair of DLL and ALL makes a Unit, devoted to track LOS or a multipath signal. Several Units are incorporated in the CADLL structure, and then able to track the different component rays from the overall incoming signal. The feedback architecture and special working strategy of CADLL boost the performances of the parameter estimation accuracy, the noise tolerance ability and the error mitigation for short-range multipath. [ABSTRACT FROM AUTHOR]

BACKGROUND: Evidence-based guidelines recommend that acutely ill hospitalized medical patients who are at risk of venous thromboembolism (VTE) should receive prophylaxis. Our aim was to characterize the clinical practices for VTE prophylaxis in acutely ill hospitalized medical patients enrolled in the International Medical Prevention Registry on Venous Thromboembolism (IMPROVE). METHODS: IMPROVE is an ongoing, multinational, observational study. Participating hospitals enroll the first 10 consecutive eligible acutely ill medical patients each month. Patient management is determined by the treating physicians. An analysis of data on VTE prophylaxis practices is presented. RESULTS: From July 2002 to September 30, 2006, 15,156 patients were enrolled from 52 hospitals in 12 countries, of whom 50% received in-hospital pharmacologic and/or mechanical VTE prophylaxis. In the United States and other participating countries, 52% and 43% of patients, respectively, should have received prophylaxis according to guideline recommendations from the American College of Chest Physicians (ACCP). Only approximately 60% of patients who either met the ACCP criteria for requiring prophylaxis or were eligible for enrollment in randomized clinical trials that have shown the benefits of pharmacologic prophylaxis actually received prophylaxis. Practices varied considerably. Intermittent pneumatic compression was the most common form of medical prophylaxis utilized in the United States, although it was used very rarely in other countries (22% vs 0.2%, respectively). Unfractionated heparin was the most frequent pharmacologic approach used in the United States (21% of patients), with low-molecular-weight heparin used most frequently in other participating countries (40%). There was also variable use of elastic stockings in the United States and other participating countries (3% vs 7%, respectively). CONCLUSIONS: Our data suggest that physicians' practices for providing VTE prophylaxis to acutely ill hospitalized medical patients are suboptimal and highlight the need for improved implementation of existing evidence-based guidelines in hospitals. [ABSTRACT FROM AUTHOR]

We present a combined experimental and theoretical study of the magnetization of one-dimensional atomic cobalt chains deposited on a platinum surface. We discuss the intrinsic magnetization parameters derived by X-ray magnetic circular dichroism measurements and the observation of ferromagnetic order in one dimension in connection with the presence of strong, dimensionality-dependent anisotropy energy barriers of magnetocrystalline origin. An explicit transfer matrix formalism is developed to treat atomic chains of finite length within the anisotropic Heisenberg model. This model allows us to fit the experimental magnetization curves of cobalt monatomic chains, measured parallel to the easy and hard axes, and provides values of the exchange coupling parameter and the magnetic anisotropy energy consistent with those reported in the literature. The analysis of the spin–spin correlation as a function of temperature provides further insight into the tendency to magnetic order in finite-sized one-dimensional systems. [ABSTRACT FROM AUTHOR]

Although intravenous (i.v.) heparin is widely used as the first line treatment for cerebral venous and sinus thrombosis (CVST), the most appropriate therapy for this disease is still controversial. We report 2 cases of CVST who were successfully treated by means of loco-regional thrombolysis with urokinase. In the first case we chose this treatment instead of i.v. heparin because clinical conditions of the patient appeared critical for life on hospital admission; in the second case loco-regional thrombolysis was performed because a full-dose heparin treatment over 8 days failed to improve the clinical picture of the patient. In the literature, there are no established criteria for the use of loco-regional thrombolysis in CVST. On the basis of our own experience and few previous reports on the matter, we suggest that loco-regional thrombolysis should be considered an appropriate treatment for CVST when patients are at life risk, when an involvement of deep cerebral veins is present or when, after full heparinization, patients are doing poorly clinically. [ABSTRACT FROM AUTHOR]

Focuses on ultrathin ferromagnetic films of cobalt (Co), grown on a stepped copper (Cu)(100) substrate, which exhibit shifted magnetization curves. Information on shifted magnetization curves; Field dependence of the film magnetization.

Epitaxial Cu/Ni/Cu/Si(001) magnetic films have been studied in the thickness range (17-120 Å) where a uniaxial anisotropy favoring the direction perpendicular to the film plane is dominant over the easy-plane dipolar interaction. Using magneto-optic magnetometry and Brillouin light scattering we show that on decreasing an in-plane magnetic field the perpendicular component of the magnetization breaks into domains. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Evaluating and testing hydration status is increasingly requested by rehabilitation, sport, military and performance-related activities. Besides commonly used biochemical hydration assessment markers within blood and urine, which have their advantages and limitations in collection and evaluating hydration status, there are other potential markers present within saliva, sweat or tear. This literature review focuses on body fluids saliva, sweat and tear compared to blood and urine regarding practicality and hydration status influenced by fluid restriction and/or physical activity. The selected articles included healthy subjects, biochemical hydration assessment markers and a well-described (de)hydration procedure. The included studies (n=16) revealed that the setting and the method of collecting respectively accessing body fluids are particularly important aspects to choose the optimal hydration marker. To obtain a sample of saliva is one of the simplest ways to collect body fluids. During exercise and heat exposures, saliva composition might be an effective index but seems to be highly variable. The collection of sweat is a more extensive and time-consuming technique making it more difficult to evaluate dehydration and to make a statement about the hydration status at a particular time. The collection procedure of tear fluid is easy to access and causes very little discomfort to the subject. Tear osmolarity increases with dehydration in parallel to alterations in plasma osmolality and urine-specific gravity. But at the individual level, its sensitivity has to be further determined. [ABSTRACT FROM AUTHOR]

Presents a study on the ground state of antiferromagnetic systems in a magnetic field and in the presence of surfaces. Properties of materials made of ferromagnetic films antiferromagnetically coupled; Discussion on semi-infinite antiferromagnetic system; Derivation of equations; Results.

Provides information on a study that examined the spin-wave spectrum of multilayer structures Fe(110)/Nm(111), with different thicknesses of the noble metal interlayer using a surface-sensitive M ö ssbauer spectroscopy technique.

The in-plane rotation of magnetic stripe domains in a 65-nm magnetostrictive Fe0.8Ga0.2 epitaxial film was investigated combining magnetic force microscopy, vibration sample magnetometry, and x-ray resonant magnetic scattering measurements. We analyzed the behavior of the stripe pattern under the application of a bias magnetic field along the in-plane direction perpendicular to the stripe axis, and made a comparison with the analogous behavior at remanence. The experimental results have been explained by means of micromagnetic simulations, supported by energy balance considerations. Fields smaller than ~400 Oe do not induce any stripe rotation; rather, a deformation of the closure domains pattern was evidenced. Larger fields produce a sudden rotation of the stripe structure. [ABSTRACT FROM AUTHOR]

Brillouin light scattering was applied to measure the evolution of spin waves in exchange-coupled [Co/Pd]-NiFe films with out-of-plane/in-plane magnetic anisotropy. Tunable tilting of the magnetization has important effects on the spin wave frequency gap: a substantial increase is observed with decreasing the soft NiFe thickness, while seemingly insignificant tilting angles cause a strong reduction with respect to a film with only the hard [Co/Pd] component. The spin wave frequency is reproduced also in samples, with increased thickness of the upper Pd layer, where a sudden modification in the tilting at the hard/soft interface is caused by the weakening of interlayer exchange. [ABSTRACT FROM AUTHOR]

Co/Ni(lll) multilayers with variable cobalt thickness iCo between 0.15 and 0.35 nm and fixed nickel thickness tNi = 0.6 nm were grown on a Pt( 1.6 nm)/Ta(3 nm) substrate by dc magnetron sputtering. A strong perpendicular magnetic anisotropy was found both using vibrating sample magnetometry and Brillouin light scattering from thermally excited spin waves. The simultaneous presence of two spin-wave modes, for a range of magnetic fields H applied in plane between ≈2.5 and 5 kOe, was connected with the presence of bubble domains, revealed by polar Kerr microscopy. The lower frequency mode (v ≈ 3 GHz), which exhibits a smooth dependence on the strength of H, was attributed to harmonic oscillations of the domain walls. The higher frequency mode, which displayed the typical field behavior of a film with a perpendicular anisotropy, was interpreted as the superposition of two nearly degenerate modes, associated, respectively, with the in-phase and out-of-phase precession of the spins in the bubble array. The higher frequency mode also displayed an unprecedented, nonmonotonic dependence on cobalt thickness, reflecting the nonmonotonic tCo dependence of the effective anisotropy field of the multilaye. [ABSTRACT FROM AUTHOR]

Abstract: The histone deacetylase inhibitor (HDACi) valproic acid (VPA) has been shown to be active on acute myeloid leukemia (AML) and refractory anemia with excess of blasts (RAEB). Thirty-one elderly AML/RAEB patients (AML n =25; RAEB n =6) with a high rate of comorbidity were entered in a phase II study with low-dose cytarabine (Ara-C) and VPA. Fitness was evaluated by means of the Comprehensive Geriatric Assessment (CGA), including the Cumulative Illness Rating Scale (CIRS) score, the self-sufficiency scores of Activity of Daily Living (ADL) and Instrumental Activity of Daily Living (IADL). Eight patients obtained a lasting complete remission and 3 other patients obtained hematologic improvement for a total response rate of 35%. Five of 11 responding patients were relapsed or resistant after a previous treatment with Ara-C. Seven of 11 responding patients were assessed as frail at enrolment and/or had IADL impairment. Grades 3 and 4 toxicities were mainly hematological. Low-dose Ara-C and VPA is a relatively non-toxic combination with good therapeutic activity in elderly patients with AML/RAEB. This therapeutic approach represents an alternative treatment for patients who cannot undergo standard induction therapy. [Copyright &y& Elsevier]

Acutely ill, hospitalized medical patients are at risk of VTE. Despite guidelines for VTE prevention, prophylaxis use in these patients is still poor, possibly because of fear of bleeding risk. We used data from the International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) to assess in-hospital bleeding incidence and to identify risk factors at admission associated with in-hospital bleeding risk in acutely ill medical patients. [ABSTRACT FROM AUTHOR]

Ferromagnetic materials based on the Heusler alloy Ni2MnGa have been recognized as interesting actuating materials. Large strains can be obtained by applying an external magnetic field acting on the reorientation of the mesoscopic structure of martensite. Even if a great part of the investigation has been performed on single crystals, an interest exists for the development of polycrystalline technology. It has been recognized that, in order to balance the strong uncoupling effect due to the large number of fixed interfaces (e.g. the grain boundaries), the polycrystalline sample should have some texture. This should result in some pre-orientation of the twinned martensitic structure and, if possible, in a modification of the random distribution of the easy axis orientation within the material.Strong material texturing can be obtained basically by using directional solidification, rapid solidification techniques or plastic deformation. The effects of directional solidification, and of melt spinning have been evaluated in the past. In the present work, we report on successfully plastic deformation of polycrystalline NiMnGa alloys. In literature, there are few (if any) papers devoted to this topic. The great brittleness of the alloy at room temperature is well known. The rare attempts performed to deform the material are reported as failures. The approach used here is based on the hot working of NiMnGa ingots in special metallic cans filled with Argon and sealed. Hot deformation of a 7×7×40 mm3 small slab down to 1.25×11.9×130 mm3 was successful. Even after this severe plastic deformation, it was possible to easily remove the deformed material from the special can. The structural and functional characterization of the final product, which maintained the martensitic transformation, will be presented and discussed. [Copyright &y& Elsevier]

Seventeen medical homes (MH) were established in the Local Health Authority (LHA) of Parma, Emilia-Romagna, Italy, between 2011 and 2016. MH implementation was associated with a 7% decrease in emergency department (ED) utilization (HR=0.93; 95% CI: 0.92-0.94). Conclusions Accounting for pre-existing differences in utilization, this MH initiative was associated with some modest improvements in utilization measures, some of which depended on when the MH was implemented, how long it had been open, or its complexity. [Extracted from the article]

To analyze the prevalence of polypharmacy and potentially inappropriate medications (PIMs) in the older population of the Parma Local Health Authority (LHA), Italy, and to evaluate their associations with patients' and general practitioners' (GPs) characteristics. Polypharmacy (>5 medications) and excessive polypharmacy (>10 medications) were indicated by adding the total number of medications per quarter, averaged over four quarters. The insight into patients' and GPs' characteristics associated with polypharmacy and PIMs may help to enhance the prescribing strategies in this vulnerable patient population. [Extracted from the article]

In this work, we present a nuclear magnetic resonance (NMR) study of the spin dynamics in the rare-earth-based low-dimensional molecular magnetic chains Eu(hfac)3NITEt and Gd(hfac)3NITEt (in short, Eu-Et and Gd-Et). Although both samples are based on the same chemical building block, [(hfac)3NITEt], their magnetic properties change dramatically when the Eu3+ ion, which is nonmagnetic at low temperatures, is substituted by the magnetic Gd3+ ion. The present proton NMR investigation shows that, down to the lowest investigated temperature (T=1.5 K for Gd-Et and T=3 K for Eu-Et), the Eu-Et chain behaves as a one-dimensional Heisenberg model with antiferromagnetic exchange coupling (J=-20 K) between s=1/2 organic radicals, and has a T-independent exchange frequency (ωe=2.6?1012 rad/s). In the Gd-Et chain, in contrast, a competition arises between nearest-neighbor ferromagnetic coupling and next-nearest-neighbor antiferromagnetic coupling; moreover, two phase transitions have previously been found, in agreement with Villain's conjecture: a first transition, at T0=2.2 K, from a high temperature paramagnetic phase to a chiral spin liquid phase, and a second transition, at TN=1.9 K, to a three-dimensional helical spin solid phase. Contrary to the Eu-Et chain (whose three-dimensional ordering temperature is estimated to insurge at very low, TN≈0.3 K), critical spin dynamics effects have been measured in the Gd-Et chain on approaching TN=1.9 K: namely, a divergence of the proton nuclear spin-lattice relaxation rate 1/T1, which in turn produces a sudden wipe-out of the NMR signal in a very narrow (ΔT~0.04 K) temperature range above TN. Below TN, an inhomogeneous broadening of the NMR line indicates a complete spin freezing. At T0=2.2 K, instead, such critical effects are not observed because NMR measurements probe the two-spin correlation function, while the chiral spin liquid phase transition is associated with a divergence of the four-spin correlation function. [ABSTRACT FROM AUTHOR]

The article cites a study on the hemosiderosis and dietary iron in birds from the Sturnidae and Paradisaedae families. Liver iron levels in the said groups were monitored after the initial evaluation that involves feeding trials and diet changes instituted in 1988. Atomic absorption spectroscopy was used to determine total hepatic iron concentration in liver specimens. It is found that two families of the order Passeriformes, Paradisaedae and Sturnidae showed outstanding liver iron concentrations. It is also revealed that livers from zoo birds fed diets of known iron content did not differ statistically from those with unknown diet history.