Shot noise in magnetic double-barrier tunnel junctions

We calculate shot noise and the corresponding Fano factors in magnetic double-barrier tunnel junctions. Two situations are analyzed: (i) the central metallic layer is nonmagnetic while the external ones are ferromagnetic, and (ii) all of the metallic layers are ferromagnetic. In the latter case, the number of various magnetic configurations of the junctions is larger, which improves the functionality of such devices. The corresponding shot noise and Fano factor are shown to depend on the magnetic configuration of the junctions. The effect of spin relaxation in the central layer is also taken into account. The theoretical results are compared with experimental data on the shot noise in Fe/MgO/Fe/MgO/Fe structuresThis work is supported by the National Science Center in Poland as a research project in the years 2011–2014 and by the Polish National Center of Research and Development within the framework of the European project Era.Net.Rus “SpinBarrier” for the years 2012–2014. The work in Madrid has been supported by the Spanish MINECO (Grant No. MAT2012-32743, CONSOLIDER CSD2007-00010) and Comunidad de Madrid (Grant No. P2009/MAT-1726

Two types of vascularisation of intramural uterine leiomyomata revealed by corrosion casting and immunohistochemical study

The blood supply of myomatous uteri collected upon autopsy was examined. The uterine vascular beds were perfused via afferent vessels with fixative followed by Mercox resin and corroded after polymerisation of the resin. The vascular casts thus obtained were examined using scanning electron microscopy. The vascular system of the uterine fibroids was also examined using immunohistochemical analysis (FVIII, factor VIII-related antigen)

Eta invariants for flat manifolds

Using H. Donnelly result from the article "Eta Invariants for G-Spaces" we calculate the eta invariants of the signature operator for almost all 7-dimensional flat manifolds with cyclic holonomy group. In all cases this eta invariants are an integer numbers. The article was motivated by D. D. Long and A. Reid article "On the geometric boundaries of hyperbolic 4-manifolds, Geom. Topology 4, 2000, 171-178Comment: 18 pages, a new version with referees comment

AWG-DBR-based WDM transmitter fabricated in an InP generic foundry platform

We report a novel narrow-linewidth WDM transmitter operating at 10 Gbps per transmission channel with 275 kHz optical linewidth. The device, which integrates an AWG-based laser using selective DBR-mirrors with a Mach-Zehnder modulator array, has been fabricated in a multi-project wafer run in a generic InP-based foundry process.</p

Shot noise in magnetic tunneling structures with two-level quantum dots

We analyze shot noise in a magnetic tunnel junction with a two-level quantum dot attached to the magnetic electrodes. The considerations are limited to the case when some transport channels are suppressed at low temperatures. Coupling of the two dot's levels to the electrodes are assumed to be generally different and also spin dependent. To calculate the shot noise we apply the approach based on the full counting statistics. The approach is used to account for experimental data obtained in magnetic tunnel junctions with organic barriers. The experimentally observed Fano factors correspond to the super-Poissonian statistics, and also depend on relative orientation of the electrodes' magnetic moments. We have also calculated the corresponding spin shot noise, which is associated with fluctuations of spin current

Application of acrylic emulsion Liquitex R (Binney and Smith) for the preparation of injection specimens and immunohistochemical studies - an observation

Application of acrylic emulsion Liquitex R for injection studies of the vascular system of human myomatous uteri was analysed. It was found that this injection mass does not penetrate the capillary bed of human organs, but it is useful in studies carried out on the blood supply of the human organs removed from cadavers. The results were compared with the studies performed with the help of immunohistochemical tests for von Willebrandt's factor

Ig heavy chain gene rearrangements in T-cell acute lymphoblastic leukemia exhibit predominant DH6-19 and DH7-27 gene usage, can result in complete V-D-J rearrangements, and are rare in T-cell receptor αβ lineage

Rearranged IGH genes were detected by Southern blotting in 22% of 118 cases of T-cell acute lymphoblastic leukemia (ALL) and involved monoallelic and biallelic rearrangements in 69% (18/26) and 31% (8/26) of these cases, respectively. IGH gene rearrangements were found in 19% (13/69) of CD3- T- ALL and in 50% of TCRγδ+ T-ALL (12/24), whereas only a single TCRαβ+ T- ALL (1/25) displayed a monoallelic IGH gene rearrangement. The association with the T-cell receptor (TCR) phenotype was further supported by the striking relationship between IGH and TCR delta (TCRD) gene rearrangements, ie, 32% of T-ALL (23/72) with monoallelic or biallelic TCRD gene rearrangements had IGH gene rearrangements, whereas only 1 of 26 T-ALL with biallelic TCRD gene deletions contained a monoallelic IGH gene rearrangement. Heteroduplex polymerase chain reaction (PCR) analysis with VH and DH family- specific primers in combination with a JH consensus primer showed a total of 39 clonal products, representing 7 (18%) VH-(DH-)JH joinings and 32 (82%) DH- JH rearrangements. Whereas the usage of VH gene segments was seemingly random, preferential usage of DH6-19 (45%) and DH7-27 (21%) gene segments was observed. Although the JH4 and JH6 gene segments were used most frequently (33% and 21%, respectively), a significant proportion of joinings (28%) used the most upstream JH1 and JH2 gene segments, which are rarely used in precursor-B-ALL and normal B cells (1% to 4%). In conclusion, the high frequency of incomplete DH-JH rearrangements, the frequent usage of the more downstream DH6-19 and DH7-27 gene segments, and the most upstream JH1 and JH2 gene segments suggests a predominance of immature IGH rearrangements in immature (non-TCRαβ+) T-ALL as a result of continuing V(D)J recombinase activity. More mature αβ-lineage T-ALL with biallelic TCRD gene deletions apparently have switched off their recombination machinery and are less prone to cross-lineage IGH gene rearrangements. The combined results indicate that IGH gene rearrangements in T-ALL are postoncogenic processes, which are absent in T-ALL with deleted TCRD genes and completed TCR alpha (TCRA) gene rearrangements.</p

Ig heavy chain gene rearrangements in T-cell acute lymphoblastic leukemia exhibit predominant DH6-19 and DH7-27 gene usage, can result in complete V-D-J rearrangements, and are rare in T-cell receptor αβ lineage

Rearranged IGH genes were detected by Southern blotting in 22% of 118 cases of T-cell acute lymphoblastic leukemia (ALL) and involved monoallelic and biallelic rearrangements in 69% (18/26) and 31% (8/26) of these cases, respectively. IGH gene rearrangements were found in 19% (13/69) of CD3- T- ALL and in 50% of TCRγδ+ T-ALL (12/24), whereas only a single TCRαβ+ T- ALL (1/25) displayed a monoallelic IGH gene rearrangement. The association with the T-cell receptor (TCR) phenotype was further supported by the striking relationship between IGH and TCR delta (TCRD) gene rearrangements, ie, 32% of T-ALL (23/72) with monoallelic or biallelic TCRD gene rearrangements had IGH gene rearrangements, whereas only 1 of 26 T-ALL with biallelic TCRD gene deletions contained a monoallelic IGH gene rearrangement. Heteroduplex polymerase chain reaction (PCR) analysis with VH and DH family- specific primers in combination with a JH consensus primer showed a total of 39 clonal products, representing 7 (18%) VH-(DH-)JH joinings and 32 (82%) DH- JH rearrangements. Whereas the usage of VH gene segments was seemingly random, preferential usage of DH6-19 (45%) and DH7-27 (21%) gene segments was observed. Although the JH4 and JH6 gene segments were used most frequently (33% and 21%, respectively), a significant proportion of joinings (28%) used the most upstream JH1 and JH2 gene segments, which are rarely used in precursor-B-ALL and normal B cells (1% to 4%). In conclusion, the high frequency of incomplete DH-JH rearrangements, the frequent usage of the more downstream DH6-19 and DH7-27 gene segments, and the most upstream JH1 and JH2 gene segments suggests a predominance of immature IGH rearrangements in immature (non-TCRαβ+) T-ALL as a result of continuing V(D)J recombinase activity. More mature αβ-lineage T-ALL with biallelic TCRD gene deletions apparently have switched off their recombination machinery and are less prone to cross-lineage IGH gene rearrangements. The combined results indicate that IGH gene rearrangements in T-ALL are postoncogenic processes, which are absent in T-ALL with deleted TCRD genes and completed TCR alpha (TCRA) gene rearrangements.</p

Calculation of atomic spontaneous emission rate in 1D finite photonic crystal with defects

We derive the expression for spontaneous emission rate in finite one-dimensional photonic crystal with arbitrary defects using the effective resonator model to describe electromagnetic field distributions in the structure. We obtain explicit formulas for contributions of different types of modes, i.e. radiation, substrate and guided modes. Formal calculations are illustrated with a few numerical examples, which demonstrate that the application of effective resonator model simplifies interpretation of results.Comment: Cent. Eur. J. Phys, in pres