Thermal Expansion Coefficient and Spontaneous Volume Magnetostriction of Fe-Ni (fcc) Alloys

The thermal expansion coefficient α of Fe-Ni (fcc) alloys was measured in the range from 800℃ to room temperature. Below the Curie temperature T_c, the α-T curve exhibits an anomaly corresponding to the spontaneous volume magneto-striction ω_s. The \u27paramagnetic\u27 thermal expansion coefficient α_p below T_c was determined by the extrapolation of the α-T curve above T_c, and the value of ω_s was estimated from the difference between α_p and α below T_c. The relation between ω_s and the change of T_c with pressure was discussed. The α_p vs. composition curve at a fixed temperature shows a minimum around the invar alloys. This minimum corresponds to the anomaly in the elastic moduli vs. composition curves. It is thus pointed out that the lattice energy must be considered in addition to the magnetic energy in discussing the origin of the invar properties

Variation of Internal Friction with Magnetization in Nickel

The internal friction Q^ of nickel annealed at 1000℃ for 10hr was measured in a magnetic field by the electrostatic driving method. The results obtained are as follows : (1) With decreasing magnetic field H from a magnetically saturated state, Q^ increases from about H=30 Oe and shows a maximum at H=15 Oe. (2) The magnetic hysteresis loss Q^_h was separated from the whole Q^ through measurement of the dynamic stress with an interference comparameter. (3) When Q^_h is expressed as a function of magentization I/I_s, Q^_h shows a maximum at I/I_s=0.6 ; it becomes smaller with increasing driving frequency f and vanishes at f=5.8 kHz

Specific Heats of Fe-Ni (fcc) Alloys at High Temperature

Specific heats at constant pressure, C_p, of Fe-Ni (fcc) alloys have been measured a temperatures 300～1000 K. For alloys containing more than 50%Ni, the C_p-T curve shows a sharp λ-type peak at ferromagnetic Curie temperature. For the alloys less in concentration of nickel, however, only a dull peak is observed. The C_p-T curve is analyzed using the values of thermal expansion coefficient and of compressibility measured on the same conditions, separating the magnetic contribution from total specific heats

Thermal Expansion Coefficient of Fe-Ni(fcc) Alloys

The thermal expansion coefficient, α, was measured over the range from 800℃ to room temperature for Fe-Ni(fcc) alloys. The results obtained are as follows : (1) On the temperature vs. α curve, a peak appears at the Curie temperature, T_c, in the composition range above 42% of Ni but none in the range of 42-30% of Ni. (2) T_c of the alloys with more than 42% of Ni is present in the γ phase at a temperature higher than the upper limit for (α+γ) mixture phase in the equilibrium diagram. (3) the value of α_P obtained from α by climinating the magnetic contribution shows a minimum in the Invar range as in the case of α. This may suggest that the interatomic cohesive force must be considered in addition to the magnetic effect in making clear the origin of Invar property

The Effect of Carbon Addition on the Magnetic Shunt Properties of M.S.O. Alloy

The magnetic shunt properties of a kind of M.S.O. Alloy (31%Ni, 8.5%Cr and rest Fe) containing C from 0.019 to 0.150% were studied. The magnetization curves at 0°to 40℃ were measured by the ballistic method. The dimension of specimen was 0.4 cm in diameter, 3.1 cm in length, and so the demagnetization factor N was 0.30. The experimental results on magnetic shunt properties are summarised as follows : (1) With increasing C addition, the permeability decreases at first and then increases slightly through a feeble minimum. It is assumed that the former decreasing is due to the impurity of C and the latter increasing due to the formation of Fe_6Cr_C_6 which is speculated by the microscopic. texture and the calculation. (2) The temperature coefficient of permeability becomes larger with increasing C addition, and its linearity becomes worse

IgA Response of BALB/c Mice to Orally Administered Salmonella typhimurium Flagellin-Displaying T2 Bacteriophages

Salmonella typhimurium antigens were displayed on the capsid of a T2 bacteriophage to explore the potential of phage display for an oral vaccine. Segments of the flagellin proteins FliC (H1 antigen) and FljB (H2) were fused to the N-terminal of T2 phage SOC to give two recombinant phages, T2FliCm and T2FljBm. Over 14 days, 19 BALB/c mice were orally administered twice, either with purified recombinant FliCm and FljBm protein, or T2FliCm and T2FljBm with or without host Escherichia coli. Feces were sampled over 10 weeks and examined for phage by plaque assay and for the presence of mucosal IgA by ELISA. Relatively few phages were detected relative to the amount administered (up to 8.21 Â 10 3 PFU/ g faeces) and none were detected five days after initial administration. The administration of a large number of phages appeared to cause no clinical symptoms. IgA concentration in feces peaked around four weeks after the second administration and subsided after eight weeks. The highest relative titers were observed in the protein group (0.37% for anti-FliCm and 0.22% for anti-FljBm) and the mouse group which received no E. coli (0.33% and 0.35%) despite the theoretical amount of protein contained in a phage dose being at least 80-465 times lower than the protein dose administered. The possibility that the immunostimulatory properties of the phage create an adjuvant effect to enhance the immunogenic properties of the displayed proteins is discussed. We conclude that phage may be valuable as a vector for oral vaccines

The Effect of Grazing on Fecal Shedding of Pathogenic Escherichia coli in Beef Cattle

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Uptake and Degradation of Bacteriophages by Liver Sinusoidal Endothelial Cells

Bacteriophages (briefly, “phages”) are viruses which target bacteria, and are non-infectious to eukaryotic cells. It is estimated that more than 30 billion phages cross into the human body from the gut each day1, and eventually need to be cleared from the blood circulation. The liver plays a central role in pathogen clearance, and liver sinusoidal endothelial cells (LSECs), which form the lining of the numerous capillaries in the liver, are therefore on the front lines for this removal process. However, despite their strategic location and efficiency in removing small (<200 nm) particles2, LSECs have historically been poorly studied in terms of removal of phages. We hypothesized that LSECs play a critical role in the removal of phages from the bloodstream through endocytic uptake and lysosomal degradation, and used GFP-labeled T4 bacteriophages as a model system to study this clearance process. Uptake and trafficking of phages in primary cultured LSECs was monitored by deconvolution microscopy on both short (1 hour) and long (24 hours) term timescales, and structured illumination microscopy was used to confirm the identity of the LSECs using their unique, sub-diffraction scale morphological features: tiny holes called fenestrations. After being taken up by the cells, the phages were rapidly transported to late endosomes/lysosomes, as confirmed by colocalization studies with an LSEC-specific lysosomal vital marker. Challenging the LSEC cultures with radiolabeled phages for up to 24 hours showed that the phages were degraded about 4h after being taken up by the cells, with degradation products being increasingly released to the spent medium up to about 18h after uptake. In conclusion, our novel finding that LSECs internalize and degrade bacteriophages lends support to the hypothesis that LSECs play an important role in the clearance of blood borne phages