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Daishi Shimada,1 Motoyasu Sagawa,2 Masafumi Seki1,3 1Division of Infectious Diseases, Tohoku Medical and Pharmaceutical University Hospital, Sendai City, Japan; 2Division of Endoscopy, Tohoku Medical and Pharmaceutical University Hospital, Sendai City, Japan; 3Division of Infectious Diseases and Infection Control, Saitama Medical University International Medical Center, Hidaka City, JapanCorrespondence: Masafumi Seki, Division of Infectious Diseases and Infection Control, Saitama Medical University International Medical Center, Yamane 1397-1, Hidaka City, Saitama, Japan, Tel +81-42-984-4392, Fax +81-42-984-0280, Email sekimm@saitama-med.ac.jpBackground: Higher rates of diagnosis of pulmonary Mycobacterium avium-intracellulare complex (MAC) disease by bronchoscopy (BS) in patients who could not diagnose by sputum cultures have been suggested, but the detailed utility of BS, especially in combination with anti-glycopeptidolipid-core IgA antibodies (anti-MAC Ab), is still unclear.Methods: A total of 111 patients at our hospital with suspected MAC who underwent BS because they were sputum-negative from April 2018 to March 2022 were analyzed prospectively. These patients were also divided into two groups, anti-MAC Ab-positive and anti-MAC Ab-negative, and compared.Results: A total of 111 patients underwent BS, though 95 (38.0%) of 250 enrolled patients were sputum smear/culture-positive. The age of the 111 patients was 69.14 (31.0– 89.0) years, and 90 (81.0%) were female; 69 (62.2%) of 111 patients were either smear-positive (n = 42, 37.8%) or culture-positive (n = 27, 24.3%) by BS. Of the total 111 patients, 69 (62.2%) were anti-MAC Ab-positive and 57 (82.6%) of 69 patients were also positive by BS. In contrast, only 12 (28.6%) of the 42 anti-MAC Ab-negative patients were positive by BS. The sensitivity and specificity of anti-MAC Ab for positive by BS were 82.6% and 71.4%, respectively, and the area under the curve (AUC) on receiver-operating characteristic (ROC) curve analysis was 0.807.Conclusion: BS and anti-MAC Ab showed similar usefulness to confirm the diagnosis in patients who could not be diagnosed by sputum examination, but pulmonary MAC disease was strongly suspected based on chest radiography/CT findings. These two examinations were correlated, and their combination appeared to provide more accurate diagnosis and earlier therapy.Keywords: anti-MAC antibody, bronchiectasis, bronchoscopy, nontuberculous mycobacteria, sputum

The crystal structure and morphology of the Nd-rich phase in postannealed sintered Nd-Fe-B hard magnets using transmission electron microscopy (TEM) was investigated. The results stated that the intragrain Nd-rich precipitates frequently disrupt magnetic domain wall arrangements, and that the magnetic interactions across thin amorphous Nd-rich phase are dominated by a simple dipole interaction.

Sintered Nd-Fe-B permanent magnets are often used in high energy product/volume ratio applications, and there is increased demand for high (BH)max magnets. New methods, such as strip casting, are used to produce high (BH)max magnets, as the formation of alpha-Fe dendrites and large Nd-rich pockets are suppressed. The microstructure of strip cast alloys is finer than ordinary cast alloys, but powder alignment does not deteriorate and Br is not reduced.

Presents a study which investigated the dependence of coercivity on the anisotropy field in the Nd[sub2]Fe[sub14]B-type sintered magnets. Contribution of cobalt to the magnetic properties of Nd-Fe-Co-B magnets; Factor which caused the existence of the ferromagnetic Dy-Fe-B phase; Tool to investigate the coercivity mechanism in the Nd-Fe-B based sintered permanent magnets.

Provides information on a study which carried out magnetic measurements on single crystals of iron-neodymium-boron permanent magnets. Methodology of the study; Results and discussion.

Presents a study which measured the complex alternating current magnetic initial susceptibility of Ho[sub2]Fe[sub14]B single crystal. Materials and methods used; Overview of a study on the domain structure of Ho[sub2]Fe[sub14]B on polycrystalline samples; Calculation of the coherent rotational susceptibility for a system with free energy.

Presents information on a study which investigated the demagnetization process of sintered rare-earth-iron-boron magnets for various configuration grains. Methodology of the study; Results and discussion.

Deals with a study that focused on the growth of single crystals of the compounds R[sub2]Fe[sub14]B some 1-4 millimeter in size for a study of the anisotropy of the magnetization curves. Factors considered in the analysis of magnetization curves; Condition that influences the decline of molecular field coefficients; Event that gives rise to interesting magnetic behavior.

Presents a study which measured the magnetization and magnetic anisotropy of R[sub2]Co[sub14]B and Nd[sub2](Fe[sub1-x]Co[subx])[sub14]B on single crystals. Method used in measuring the basal plane anisotropy of Gd[sub2]Co[sub14]B at 77 K; Illustration of the planar anisotropy of the cobalt sublattice; Mechanism which results in a rapid reduction of the planar anisotropy of the rare-earth sublattice magnetization and anisotropy.

Presents a Mössbauer study of the compositional series Nd[sub2](Fe[sub1-x]Co[subx])[sub14]B. Preparation of the compositional series samples; Analysis of the Mö ssbauer spectra typical of medium and high cobalt concentrations.