Perception of unfamiliar caregivers during sickness - Using the new Caregiver Perception Task (CgPT) during experimental endotoxemia.

Social withdrawal is a well-established part of sickness behavior, but in some contexts sick animals might gain from keeping close instead of keeping away. For instance, sick individuals are more willing to be near known individuals who can provide care and safety (close others) compared to when healthy. Yet, interactions with some strangers might also be beneficial (i.e., healthcare professionals), but it is not known how sickness interplay with social behavior towards such individuals. Here, we assessed if sickness affects perception of caregivers, and developed a new task, the Caregiver Perception Task (CgPT). Twenty-six participants performed the CgPT, once after an injection of lipopolysaccharide (LPS, 0.8 ng/kg body weight, n = 24), and once after an injection of saline (n = 25), one hour and forty-five minutes post-injection. During the task, participants watched short video clips of three types of caregivers: a healthcare professional taking care of a sick individual, a healthcare professional not taking care of a sick individual, and a non-healthcare professional taking care of their sick adult child or partner. After each video clip, the likability, trustworthiness, professionalism, and willingness to interact with and receive care from the caregiver were rated on visual analogue scales. Results showed that participants injected with saline rated healthcare professionals who did not take care of a sick individual less positively on all aspects compared to healthcare professionals who took care of a sick individual. Moreover, compared to saline, LPS increased the participants' willingness to receive care from healthcare professionals and non-healthcare professionals providing care, but not from healthcare professionals not providing care. Thus, our results indicate that sick individuals may approach unknown individuals with potential to provide care and support.

Substituting Chromium in Iron-Based Catalysts for the High-Temperature Water-Gas Shift Reaction.

A set of doped iron oxides (chromium, aluminum, gallium, indium, manganese, zinc, niobium) were prepared by a one-step coprecipitation/calcination approach evaluated for their WGS activity under industrially relevant conditions and characterized in detail. The WGS activity after ageing the doped catalyst for 4 days at 25 bar follows the order chromium ≈ aluminum > gallium > indium > manganese > zinc > niobium for copper-codoped catalysts. The activated catalysts predominantly consist of magnetite, irrespective of the dopant. Mössbauer spectra of aged catalysts showed that aluminum and zinc occupy both tetrahedral and octahedral sites of magnetite, while chromium, gallium, indium, manganese, and niobium preferentially substitute octahedral iron. The incorporation of trivalent metal ions of similar size to octahedral Fe3+ (i.e., chromium, aluminum, gallium) results in moderate to high CO conversion, irrespective of incorporation in tetrahedral or octahedral sites. The substitution of Fe2+ with Mn2+ results in an increased Fe3+/Fe2+ ratio. Incorporation of Zn2+ in tetrahedral sites (replacing Fe3+ ions) leads to a complex structure where the charge balance is compensated from the octahedral sites. Separate dopant metal oxide phases were observed in indium- and niobium-doped catalysts. XPS shows that copper is present as a separate phase in activated copper-codoped catalysts. Aluminum is identified as the most promising promoter for substituting chromium in commercial high-temperature WGS catalysts on the basis of their similar high CO conversion although incorporation of these dopants into the magnetite structure differed substantially.

Breaking the geometric magnetic frustration in controlled off-stoichiometric LuMn1+zO3+δ compounds.

This study explores controlled off-stoichiometric LuMn1+zO3+δ (|z| < 0.1) compounds, intended to retain the utter LuMnO3 intrinsic hexagonal symmetry and ferroelectric properties. X-ray powder diffraction measurements evidenced a single phase P63cm structure. Thermo-gravimetric experiments show a narrow impact of oxygen vacancies while a distinguishable gas exchange at ∼700 K, a surprisingly lower temperature when compared to perovskite systems. A comparison of different nominal ceramics revealed pertinent structural and magnetic property variations owing to subtle self-doping effects. Deviations from the archetypal antiferromagnetic state were detected below ∼90 K suggesting local rearrangements of the nominal Mn(3+) ions matrix, breaking the ideal geometrical spin frustration, leading to a non-compensated magnetic structure.

Direct magnetocaloric characterization and simulation of thermomagnetic cycles.

An experimental setup for the direct measurement of the magnetocaloric effect capable of simulating high frequency magnetothermal cycles on laboratory-scale samples is described. The study of the magnetocaloric properties of working materials under operative conditions is fundamental for the development of innovative devices. Frequency and time dependent characterization can provide essential information on intrinsic features such as magnetic field induced fatigue in materials undergoing first order magnetic phase transitions. A full characterization of the adiabatic temperature change performed for a sample of Gadolinium across its Curie transition shows the good agreement between our results and literature data and in-field differential scanning calorimetry.

Driving magnetostructural transitions in layered intermetallic compounds.

We report the dramatic effect of applied pressure and magnetic field on the layered intermetallic compound Pr(0.5)Y(0.5)Mn(2)Ge(2). In the absence of pressure or magnetic field this compound displays interplanar ferromagnetism at room temperature and undergoes an isostructural first order magnetic transition (FOMT) to an antiferromagnetic state below 158 K, followed by another FOMT at 50 K due to the reemergence of ferromagnetism as praseodymium orders (T(C)(Pr)). The application of a magnetic field drives these two transitions towards each other, whereas the application of pressure drives them apart. Pressure also produces a giant magnetocaloric effect such that a threefold increase of the entropy change associated with the lower FOMT (at T(C)(Pr)) is seen under a pressure of 7.5 kbar. First principles calculations, using density functional theory, show that this remarkable magnetic behavior derives from the strong magnetoelastic coupling of the manganese layers in this compound.

Heat-capacity measurements on small samples: the hybrid method.

A newly developed method is presented for measuring heat capacities on small samples, particularly where thermal isolation is not sufficient for the use of the traditional semiadiabatic heat-pulse technique. This "hybrid technique" is a modification of this heat-pulse method in case the temperature drift of the sample after the heat pulse is not linear but exponential. Deliberate extrapolations of these exponential drift curves, dependent on the evaluated relaxation time, yield reliable results for the temperature steps. The method is faster than the traditional relaxation method, and by comparing with the values published by the National Bureau of Standards (NBS) on copper, the accuracy is shown to be of the order of 1%.

Transition-metal-based magnetic refrigerants for room-temperature applications.

Magnetic refrigeration techniques based on the magnetocaloric effect (MCE) have recently been demonstrated as a promising alternative to conventional vapour-cycle refrigeration. In a material displaying the MCE, the alignment of randomly oriented magnetic moments by an external magnetic field results in heating. This heat can then be removed from the MCE material to the ambient atmosphere by heat transfer. If the magnetic field is subsequently turned off, the magnetic moments randomize again, which leads to cooling of the material below the ambient temperature. Here we report the discovery of a large magnetic entropy change in MnFeP0.45As0.55, a material that has a Curie temperature of about 300 K and which allows magnetic refrigeration at room temperature. The magnetic entropy changes reach values of 14.5 J K-1 kg-1 and 18 J K-1 kg-1 for field changes of 2 T and 5 T, respectively. The so-called giant-MCE material Gd5Ge2Si2 (ref. 2) displays similar entropy changes, but can only be used below room temperature. The refrigerant capacity of our material is also significantly greater than that of Gd (ref. 3). The large entropy change is attributed to a field-induced first-order phase transition enhancing the effect of the applied magnetic field.

[Morbidity after contralateral transplantation of the patellar ligament for cruciate ligament replacement]. / Zur Morbidität nach kontralateraler Entnahme des Lig.-patellae-Transplantats zum Kreuzbandersatz.

After cruciate ligament reconstruction using an autogenous central bone-patellar tendon-bone graft persistent complaints are described in the literature. There is the difficulty to distinguish the morbidity associated with the graft harvest and the morbidity caused by the injury and the reconstruction procedure. In order to clarify the morbidity resulting from the graft harvest alone, we evaluated those patients who had transplantat harvest from the opposite knee. Between 1990 and 1995 a central bone-tendon-bone graft has been taken from the contralateral uninjured knee in 37 patients, in 22 cases for anterior and in 15 cases for posterior cruciate ligament reconstruction. 27 patients were clinically (IKDC Score), isokinetically and radiologically followed up in an average of 25.3 months after the operation (range: 9-73 months). 21 patients were classified into IKDC group A. Except of one patient with an extension deficit of 5 degrees all others showed normal range of motion. Only 5 of 27 patients expressed minimal knee pain during vigorous activities. Three of them reported about weather sensitivity in addition. These 6 patients were ranked in group B. No patient was classified into IKDC group C or D. The isokinetic examination showed a normal level of quadriceps strength. At final followup, the technique of Blackburne and Peel was used to assess patellar height. There was no radiographic evidence of patella contracture or baja. According to our results taking the autogenous CBTB graft used for cruciate ligament reconstruction leads to no serious morbidity.

[Blunt thoracic trauma with aortic rupture and lung contusion caused by hoof kick in a 15-year-old girl. Diagnostic and therapeutic management]. / Stumpfes Thoraxtrauma mit Aortenruptur und Lungenkontusion durch Hufschlag bei einem 15jährigen Mädchen. Diagnostisches und therapeutisches Management.

The number of published cases of adolescents surviving thoracic aortic injuries with accompanying severe thoracic injuries is small. Only 20-30% of all these patients reach the trauma center alive. In the present case we demonstrate the diagnostic, operative and intensive care management in a 15-year-old girl. The exact interpretation of the AP thoracic X-ray in connection with a typical mechanism of injury led to the detection of a haemomediastinum. This is very important in the further development of diagnostics, because the conventional X-ray picture does not show significant signs in the case of an incomplete aortic rupture. Diagnostic hints have to be derived from the detection of the haemomediastinum. The girl was operated on under left heart bypass. Spinal ischaemia was absent after surgery, and renal failure also did not occur. The adjacent severe lung confusion healed under kinetic therapy with a kinetic treatment table without pulmonary complications.