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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]

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]

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.

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.

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.

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.

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]

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]

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]

This study is part of a research program that aims to develop a constitutive threedimensional model of the periodontal ligament (PDL) through the identification of pertinent material parameters. As part of this program, bovine PDL was utilized to establish stress-strain responses under tensile and compressive loading conditions. Fresh bovine molars were secured, frozen and prepared to appropriate dimensional specifications. Bar-shaped specimens that comprised portions of dentine, PDL and bone were produced. Push-pull tests were conducted using a specifically constructed loading machine. Full range monotonic stress-strain diagrams were generated. The effect of a rate increase on cyclic S-E diagrams was also determined. The influence of specimen thickness was expressed in terms of modulus of elasticity, strength, uniaxial maximizer strain, and strain energy density. The overall load-response was heavily hysteretic in compression. On the tensile side, after a steep rise, the curve tended to ftatten out asymptotically. Variations in rate that spanned four orders of magnitude had no effect on reciprocal load responses. The E-modulus was in the 4-8 MPa range, the strength of the PDL was 1-2 MPa, the maximizer strain was at 45-60% and the strain energy density ranged between 0.3 and 0.4 MPa. [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]

Cerebral venous and sinus thrombosis (CVST) is still considered a severe clinical problem that is difficult to diagnose and manage and is linked to a poor prognosis. Nonetheless, conventional cerebral angiography and magnetic resonance imaging (MRI), or more recently, MR angiography allow a more rapid and precise diagnosis, and prognosis has improved with the use of anticoagulant treatment.We report 23 cases of CVST consecutively admitted to the Institute of Neurology of the University of Parma during the period 1990–1997. In all cases diagnosis was confirmed by means of MRI or conventional angiography of brain vessels. Among the patients, 22 were female and 1 was male. In all patients, plasma levels of protein C, protein S, antithrombin III (ATIII) and antiphospholipid antibodies (APA) were evaluated. In 15 of 23 patients, the presence of factor V Leiden mutation was also determined, and found positive in 3 patients (20%). Of the 22 female patients, 15 (68%) were on low-oestrogen (containing less than 50 μg oestrogen) oral contraceptive (OC) treatment. This percentage of OC use by patients with CVST is much higher than that of the rest of the female Italian population. OC use was associated with the presence of factor V Leiden mutation in two cases, with a deficiency of protein C in 1 case and a deficiency of protein S in another.Whether low-oestrogen Ocs may induce cerebral thromboembolic events is an open matter. According to our data, it may be argued that Ocs, even if at low oestrogen content, represent a major risk factor for CVST. The use of Ocs, as is the case for systemic venous thromboembolic events, may further increase the risk of CVST in women carrying the factor V Leiden mutation or other inherited hyperthrombotic conditions. [ABSTRACT FROM AUTHOR]

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Copyright of Italian Journal of Neurological Sciences is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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.

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.