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A letter to the editor is presented in which local versus central bone marrow reticulin grading is being compared under a central pathology review in international trial.

Fe-ZSM-5 samples containing a combination of 57Fe3+ in framework (FW) and regular iron in extra-framework (EFW) sites were prepared by introducing 57Fe in hydrothermal synthesis, then exchanging Fe2+ of natural isotope composition into the lattice. The stability for one part of Fe2+ and Fe2+ ↔ Fe3+ reversibility for the other part in catalytic decomposition of N2O is demonstrated by in situ Mössbaer measurements. Formation of dinuclear FeFW–O–FeEFW pairs is not prevailing. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the PROX reaction is to reduce the CO content of hydrogen feed to proton-exchange membrane fuel cells (PEMFCs) by selective oxidation of CO in the presence of excess hydrogen. Both Pt and Pd on ceria are active in CO oxidation (without hydrogen), whereas Pd is poorly active in the presence of hydrogen. In this paper we explore the reasons for such behavior, using the same techniques for Pd/CeO2 as used for Pt/CeO2 in Part I: catalytic tests, in situ DRIFTS, high-pressure XPS, HRTEM, and TDS. We also examine the reaction mechanism of CO oxidation (without hydrogen), which does not occur via exactly the same mechanism on Pt and Pd/CeO2 catalysts. In the presence of hydrogen (PROX) at low temperature (), the formation of Pd β-hydride was confirmed by high-pressure in situ XPS. Its formation greatly suppressed the possibility of CO oxidation, because oxygen both from gas-phase and support sites reacted rapidly with hydride H to form water, which readily desorbed from Pd. Nevertheless, CO adsorption was not hampered here. These entities transformed mainly to surface formate and formyl (ies instead of oxidation as observed by DRIFTS. The participation of a low-temperature water–gas shift type reaction proposed for the platinum system (see Part I) was hindered. Increasing temperature led to decomposition of the hydride phase and a parallel increase in the selectivity toward CO oxidation. This still remained lower on Pd/CeO2 than on Pt/CeO2, however. [Copyright &y& Elsevier]

Abstract: The CO content of hydrogen feed to proton-exchange membrane fuel cells (PEMFCs) must be kept under 1–100 ppm for their proper operation. This can be achieved by using catalysts able to selectively oxidize CO in the presence of excess hydrogen (PROX). The present study reports on the mechanism of the PROX reaction on Pt/CeO2 catalyst, using catalytic tests, in situ DRIFTS, high-pressure XPS, HRTEM, and TDS techniques. Bulk metallic, pronounced adsorbate-induced surface Pt, and a small amount of oxidized Pt sites were detected by in situ high-pressure XPS under PROX conditions. The preoxidized ceria surface was strongly reduced in pure H2 but significantly reoxidized under PROX conditions (i.e., O2 +CO in excess hydrogen) at . The remaining small amount of Ce3+ decreased with increasing temperature. HRTEM found well-crystallized CeO2 particles (8–10 nm) in the case of activated (pre-oxidized) sample that transformed in a large extent to an oxygen deficient ceria supercell structure after PROX reaction. Metallic Pt particles (2–3 nm) and small (0.5–0.6 nm) Pt clusters were found by HRTEM. These findings were in accordance with the variations in relative intensity of the corresponding Pt(DRIFTS). Different types of carbonate and formate species were detected (XPS and DRIFTS). Their possible role in the reaction mechanism is discussed. Resolved OH bands could not be found by DRIFTS in the PROX reaction mixture indicating significant amount of adsorbed water in a hydrogen-bonded structure. Its presence seems to suppress hydrogen oxidation while CO oxidation still takes place, as the metallic particles are covered by CO (DRIFTS). The direct contribution of surface water in a low-temperature water–gas shift-type reaction in the PROX mixture is proposed. [Copyright &y& Elsevier]

Hydrated microcrystalline compound, V1-xCrxOy · nH2O, where x<0.063 and 4.4< n<8 and hydrated amorphous phases, CrVO4 ·H2O and Cr2V4O13 ·4H2O have been prepared using peroxo-polyacids of vanadium and chromium. The transformations of these hydrated phases upon heating were studied by TG-DTA and XRD techniques and led to three crystalline anhydrous compounds: ( i) phase V1-xCrxOy, which is closely related to the orthorhombic V2O5, ( ii) Cr2V4O13 and ( iii) monoclinic CrVO4-M. The ranges of coexistence of phases in equilibrium were also determined. [ABSTRACT FROM AUTHOR]

New two-dimensional microcrystalline V1−xCrxOy·nH2O phase, where x<0.25 and 6.4

The results of studying the magnetic properties of the components of the natural environment of the Barabinsk forest steppe accommodating the archaeological monuments dated to VI century B.C. to II century A.D. are presented. The rock magnetic model is constructed for a two-layer medium composed of modern soil and an underlying blanket substratum deposits (clay loam, sandy loam, sand). It is shown that the magnetism of the humic horizon of the soil depends on the topographic position and soil type, whereas the magnetic characteristics of the underlying substratum deposits are persistent throughout the studied territory. The ratio of the magnetic susceptibilities of the humus horizon to the substratum is K = 3-6 for the automorphic soil, K = 1-2.5 for semihydromorphic soil, and K = 0.8-1.0 for hydromorphic soil. Based on subdividing the studied territory in accordance with the values of K and the calculated amplitudes of the microanomalies of the magnetic field, the areas where application of the magnetic survey is highly promising, moderately efficient, and unpromising are outlined. The particular cases of the absence of magnetic anomalies above the archaeological objects, the false anomalies, and the chaotic patterns of the low-amplitude anomalies-all the situations when the magnetic survey is inefficient-are explained from the standpoint of the model. [ABSTRACT FROM AUTHOR]

Introduction The workup of lymphoproliferative disorders ( LPDs) involves the combined use of flow cytometry ( FC) and immunohistochemistry ( IHC). This often results in duplicate immunophenotypic testing and adds costs that may not be eligible for reimbursement based on the Medicare National Correct Coding Initiative. We aimed to establish a cost-effective diagnostic algorithm based on initial FC categorization to reduce repetitive immunophenotyping. Methods We retrospectively reviewed 242 cases of suspected LPDs with concurrent FC and IHC testing over a 12-month period. We correlated FC with surgical diagnoses and evaluated the frequency of repeat IHC testing. Results Repetitive immunophenotyping was common; overall, 85% of cases had at least one marker repeated. Concordant cases were significantly less likely to have markers repeated than discordant cases. Of concordant B cell malignancies, 57% represented recurrent disease; however, repeat marker usage was not decreased as compared to new diagnoses. The most frequently repeated markers were CD3, CD5, CD10, and CD20. Conclusions We propose that in concordant cases, CD5 and CD10 should not be repeated by IHC; this would decrease the use of these markers by 80% and 76%, respectively. We developed an algorithmic approach to IHC usage that has improved incorporation of FC data at our institution and may reduce healthcare costs. [ABSTRACT FROM AUTHOR]

A study of model systems that include sodium vanadate, sulfates of nickel, iron, and calcium, and a soda solution made it possible to determine the optimum parameters for desulfurizing high-sulfur wastes formed in the operation of heating and power plants. It is shown that when Ni/V = 0.15–0.33 and Fe/V = 0.5–0.75, 98% of the vanadium and 99.8% of the nickel are precipitated and sulfur content is no greater than 0.2 mass%. This has made it possible to obtain concentrates suitable for the smelting of complex alloys. [ABSTRACT FROM AUTHOR]