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Introduction: In recent years, there has been a growing trend among regulatory agencies to consider the use of historical controls in clinical trials as a means of improving the efficiency of trial design. In this paper, to enhance the statistical operating characteristic of Phase I dose-finding trials, we propose a novel modelassisted design method named “MEM-Keyboard”. Methods: The proposed design is based on the multisource exchangeability models (MEMs) that allows for dynamic borrowing of information from multiple supplemental data sources, including historical trial data, to inform the dose-escalation process. Furthermore, with the frequent occurrence of delayed toxicity in novel anti-cancer drugs, we extended our proposed method to handle late-onset toxicity by incorporating historical data. This extended method is referred to as “MEM-TITE-Keyboard” and aims to improve the efficiency of early clinical trials. Results: Simulation studies have indicated that the proposed methods can improve the probability of correctly selecting the maximum tolerated dose (MTD) with an acceptable level of risk, compared to designs that do not account for information borrowing and late-onset toxicity. Discussion: The MEM-Keyboard and MEM-TITE-Keyboard, easy to implement in practice, provide a useful tool for identifying MTD and accelerating drug development. [ABSTRACT FROM AUTHOR]

Most gastric cancers (GC) are adenocarcinomas, whereas GC is a highly heterogeneous disease due to its molecular heterogeneity. However, traditional morphology-based classification systems, including the WHO classification and Lauren's classification, have limited utility in guiding clinical treatment. We performed nonnegative matrix factorization (NMF) clustering based on 2752 metabolism-associated genes. We characterized each of the subclasses from multiple angles, including subclass-associated metabolism signatures, immune cell infiltration, clinic10al characteristics, drug sensitivity, and pathway enrichment. As a result, four subtypes were identified: immune suppressed, metabolic, mesenchymal/immune exhausted and hypermutated. The subtypes exhibited significant prognostic differences, which suggests that the metabolism-related classification has clinical significance. Metabolic and hypermutated subtypes have better overall survival, and the hypermutated subtype is likely to be sensitive to anti-PD-1 immunotherapy. In addition, our work showed a strong connection with previously established classifications, especially Lei's subtype, to which we provided an interpretation based on the immune cell infiltration perspective, deepening the understanding of GC heterogeneity. Finally, a 120-gene classifier was generated to determine the GC classification, and a 10-gene prognostic model was developed for survival time prediction. [ABSTRACT FROM AUTHOR]

Ferromagnetic phase of Mn-Al exhibits great potential in the rare-earth free permanent magnetic materials due to its high magnetocrystalline anisotropy, high magnetization, high Curie temperature and low cost. In this work, the strip casting technique was applied to prepare MnAl magnetic phase. X-ray diffraction and energy dispersive X-ray analyses indicate that the as-prepared Mn54Al46 strip sample consists of pure τ-MnAl magnetic phase. It is found that the composition of Mn54Al46 is suitable to prepare τ-MnAl phase during the strip casting process. The Mn54Al46 strip sample synthesized through the strip casting exhibits a fairly high magnetization of 114 emu/g under a field of 5 T, while the coercivity of iHc = 2.8 kOe, magnetization of M5T = 63.9 emu/g at room temperature can be obtained for Mn54Al46 powder sample. This preparation method can produce a large amount of τ-phase MnAl alloy and promote mass industrialized production. [ABSTRACT FROM AUTHOR]

The rare earth-Fe intermetallic compounds with planar magnetocrystalline anisotropy were deemed as hopeful candidates for microwave absorption owing to their higher Snoek’s limit as compared to the cubic spinel-type ferrites. In this work, The Y2Fe16Si alloy was massively produced through strip casting technique, and the microwave absorbing properties of Y2Fe16Si-paraffin composites were studied. The Y2Fe16Si alloy exhibits a single phase of hexagonal Th2Ni17-type structure with a planar magnetocrystalline anisotropy and has a saturation magnetization of 121 emu g−1. It was found that electromagnetic dissipation contributes to microwave absorption but is not the determinative factor in Y2Fe16Si-paraffin composites. Controlling the values of the complex permittivity and the complex permeability in a reasonable range can lead to proper impedance matching. Thus excellent microwave absorbing properties can be obtained. The sample with the mass ratio of 3:1 between Y2Fe16Si and paraffin displays high performance ascribed to its appropriate values of complex permittivity and permeability. A minimum reflection loss (RL) of  −51.6 dB is obtained with a thickness of 1.8 mm. Full covers of the effective bandwidth (RL  <  −10 dB) on the X-band and the Ku-band are achieved when the thicknesses are 1.9 mm and 1.38 mm, respectively. Hence, Y2Fe16Si exhibits excellent potential as a high-performance microwave absorbing material. [ABSTRACT FROM AUTHOR]

Mn-based Heusler alloys have attracted significant research attention as half-metallic materials because of their giant magnetocrystalline anisotropy and magnetocaloric properties. We investigate the crystal structure and magnetic properties of polycrystalline, [101]-oriented, and [100]-oriented prepared separately by arc melting, the Bridgeman method, and the flux method. All of these compounds crystallize in a Ni2In-type structure. In the lattice, Mn atoms occupy all of the 2a and a fraction of the 2d sites. Site disorder exists between Mn and Sn atoms in the 2c sites. In addition, these compounds undergo a re-entrant spin-glass-like transition at low temperatures, which is caused by frustration and randomness within the spin system. The magnetic properties of these systems depend on the crystal directions, which means that the magnetic interactions differ significantly along different directions. Furthermore, these materials exhibit a giant magnetocaloric effect near the Curie temperature. The largest value of maximum of magnetic entropy change ( occurs perpendicular to the [100] direction. Specifically, at 252 K, maximum is 2.91 and for a magnetic field of 5 and 7 T, respectively. The working temperature span over 80 K and the relative cooling power reaches 302 J/kg for a magnetic field of 7 T, which makes the compound a promising candidate for a magnetic refrigerator. [ABSTRACT FROM AUTHOR]

Mn-based intermetallic compounds have attracted much attention due to their fascinating structural and physical properties, especially their interesting hard magnetic properties. In this paper, we have summarized the magnetic and structural properties of Mn-based intermetallic compounds (MnX, where X =Al, Bi, and Ga). Various methods for synthesizing single phases of MnAl, MnBi, and MnxGa were developed in our lab. A very high saturation magnetization of 125 emu/g, coercivity of 5 kOe, and maximum energy product (BH)max of were achieved at room temperature for the pure τ-Mn–Al magnetic phase without carbon doping and the extrusion process. Low temperature phase (LTP) MnBi with a purity above 95 wt.% can be synthesized. An abnormal temperature coefficient of the coercivity was observed for the LTP MnBi magnet. Its coercivity increased with temperature from 100 K to 540 K, reached a maximum of 2.5 T at about 540 K, and then decreased slowly to 1.8 T at 610 K. The positive temperature coefficient of the coercivity is related to the evolution of the structure and magnetocrystalline anisotropy field of the LTP MnBi phase with temperature. The LTP MnBi bonded magnets show maximum energy products (BH)max of (70 kJ/m3) and (40 kJ/m3) at room temperature and 400 K, respectively. Ferrimagnetic MnxGa phases with L10 structures () and D022 structures () were obtained. All of the above structures can be described by a D022 supercell model in which 2a-Ga and 2b-Mn are simultaneously substituted. The tetragonal D022 phases of the MnxGa show high coercivities ranging from 7.2 kOe for low Mn content x = 1.8 to 18.2 kOe for high Mn content x = 3 at room temperature. The Mn1.2Ga sample exhibits a room temperature magnetization value of 80 emu/g. The hard magnetic properties of coercivity , remanence Mr= 43.6 emu/g, and were obtained at room temperature. Based on the above studies, we believe that Mn-based magnetic materials could be promising candidates for rare earth free permanent magnets exhibiting a high Curie temperature, high magnetocrystalline anisotropy, and very high coercivity. [ABSTRACT FROM AUTHOR]

Carbon was successfully introduced into NdMnxCr2−xSi2 serial compounds as an interstitial atom. The compounds with x  ⩽  0.5 keep a CeMg2Si2-type structure while the structure changes slowly with increasing manganese content. Finally, a new superstructure was found and determined for x around 1.7. All the compounds for x  =  1.1, 1.3, 1.5 and 1.7 have two magnetic phase transition temperatures around 43 and 314 K. What is more, a giant magnetocaloric effect has been observed around the lower phase transition temperature, TR ~ 51 K, in NdMn1.7Cr0.3Si2C. The maximum values of the magnetic entropy change  −ΔSM for the field change of 2 T and 5 T are 14.9 J kg−1 K−1 and 26.0 J kg−1 K−1, which means the interstitial atom effect enhanced the MCE values for 85% and 63% compared to NdMn1.7Cr0.3Si2, respectively. NdMn1.7Cr0.3Si2C with first order magnetic transition but low hysteresis losses (thermal  <  ~0.58 K; magnetic field  <  ~0.12 T) can be a candidate for magnetic refrigerator applications in the temperature region near 50 K. Besides, two field-induced magnetic phase transitions were found in NdMn1.7Cr0.3Si2C among the temperature range from 53 to 60 K, and a linear relation between the phase transition field and temperature was found and analyzed. [ABSTRACT FROM AUTHOR]

The crystal structure and magnetic properties of AlFe2−xMnxB2 (x = 0–0.5) compounds were investigated. With increasing Mn content, the magnetic properties of these compounds evolve gradually and the lattice parameters change continuously: Curie temperature (Tc) decreases from 312 K (x = 0) to 220 K (x = 0.5) and a new phase transition from the ferromagnetic state (FM) to spin-glass state (SPG) appears upon cooling. The lattice shrinks in the ab plane while it expands in the c direction. The formation of re-entrant SPG around 50 K was studied via temperature dependent ac and dc magnetization as well as the initial magnetization curves in 5 K. The reason for this glass state is the triangular configuration of magnetic atoms and the antiferromagnetic interactions introduced by Mn substitutions. The Curie transition leads to a conventional magnetocaloric effect (MCE). The Mn doping leads to a decrease in the MCE near room temperature, but there is a plane in entropy change (ΔS) for the x = 0.1 compound under low field which makes these compounds good candidates to produce composites used for magnetic refrigeration application in a wide temperature span. [ABSTRACT FROM AUTHOR]

By suppressing the growth of impurities, a melt spinning method was successfully applied to the synthesis of typical layered CeMn2Si2 and AlFe2B2 compounds. X-ray diffraction analysis showed that CeMn2Si2 and AlFe2B2 had good purity and crystallized in ThCr2Si2- and AlFe2B2-type structures, respectively. The differences among three -type structures were also analyzed. The magnetic properties were investigated by magnetic measurements and electronic structure calculations. It was found that the Fe moment of AlFe2B2 reaches 1.32 μB at 5 K, which fits well with the calculated result of 1.44 μB at 0 K, and that the isothermal magnetic entropy change reaches 7.2 J kg−1 K−1 at 5 T, which shows great potential for room-temperature refrigeration applications. [ABSTRACT FROM AUTHOR]