Long-range ferromagnetic correlations between Anderson impurities in a semiconductor host

We study the two-impurity Anderson model for a semiconductor host using the quantum Monte Carlo technique. We find that the impurity spins exhibit ferromagnetic correlations with a range which can be much more enhanced than in a half-filled metallic band. In particular, the range is longest when the Fermi level is located above the top of the valence band and decreases as the impurity bound state becomes occupied. Comparisons with the photoemission and optical absorption experiments suggest that this model captures the basic electronic structure of Ga_{1-x}Mn_xAs, the prototypical dilute magnetic semiconductor (DMS). These numerical results might also be useful for synthesizing DMS or dilute-oxide ferromagnets with higher Curie temperatures.Comment: 4 pages, 4 figure

Wheat‐ghretropins: novel ghrelin‐releasing peptides derived from wheat protein

Ghrelin is an endogenous orexigenic hormone mainly produced by stomach cells and is reported to influence appetite, gastrointestinal motility and growth hormone secretion. We observed that enzymatic digest of wheat gluten stimulated ghrelin secretion from mouse ghrelinoma 3-1, a ghrelin-releasing cell line. Further on, we characterized the ghrelin-releasing peptides present in the digest by comprehensive peptide analysis using liquid chromatography-mass spectrometry and structure-activity relationship. Among the candidate peptides, we found that SQQQQPVLPQQPSF, LSVTSPQQVSY and YPTSL stimulated ghrelin release. We then named them wheat-ghretropin A, B and C, respectively. In addition, we observed that wheat-ghretropin A increased plasma ghrelin concentration and food intake in mice after oral administration. Thus, we demonstrated that wheat-ghretropin stimulates ghrelin release both in vitro and in vivo. To the best of our knowledge, this is the first report of a wheat-derived exogenous bioactive peptide that stimulates ghrelin secretion

Secular trends and features of thalamic hemorrhages compared with other hypertensive intracerebral hemorrhages: an 18-year single-center retrospective assessment

IntroductionTrends regarding the locations of hypertensive cerebral hemorrhages are unclear. To clarify hypertensive hemorrhage trends, we investigated intracerebral hemorrhages (ICHs) over an 18-year period, focusing on thalamic hemorrhages compared with other sites of hemorrhages.MethodsWe reviewed the cases of patients hospitalized for hypertensive ICH in 2004–2021 at our hospital; 1,320 eligible patients were registered with a primary ICH/intraventricular hemorrhage. After exclusion criteria were applied, we retrospectively analyzed 1,026 hypertensive ICH cases.ResultsThe proportions of thalamic and subcortical hemorrhages increased over the 18-year period, whereas putaminal hemorrhage decreased. Multivariate logistic regression analyses revealed that for thalamic hemorrhage, ≥200 mmHg systolic blood pressure (p = 0.031), bleeding <15 mL (p = 0.001), and higher modified Rankin scale (mRS) score ≥ 4 at discharge (p = 0.006) were significant variables in the late period (2013–2021) versus the early period (2004–2012), whereas for putaminal hemorrhage, significant factors in the late period were triglyceride <150 mg/dL (p = 0.006) and mRS score ≥ 4 at discharge (p = 0.002). Among the features of the thalamic hemorrhages in the late period revealed by our group comparison with the putaminal and subcortical hemorrhages, the total and subcortical microbleeds were more notable in the thalamic hemorrhages than in the other two types of hemorrhage, whereas cerebellar microbleeds were more prominent when compared only with subcortical hemorrhages.DiscussionOur findings revealed an increasing trend for thalamic hypertensive hemorrhage and a decreasing trend for putaminal hemorrhage. The thalamic hemorrhage increase was observed in both young and older patients, regardless of gender. The main features of thalamic hemorrhage in the late period versus the early period were decrease in larger hemorrhage (≥15 mL) and an increase in cases with higher systolic blood pressure (at least partially involved a small number of untreated hypertensive patients who developed major bleeding). The total and subcortical microbleeds were more notable in the thalamic hemorrhages of the late period than in the putaminal and subcortical hemorrhages. These results may contribute to a better understanding of the recent trends of hypertensive ICHs and may help guide their appropriate treatments for this condition

Cochlear Nerve Action Potential Monitoring with the Microdissector in Vestibular Schwannoma Surgery

We developed a cochlear nerve action potential (CNAP) monitoring technique using a microdissector and compared the results of CNAP and auditory brainstem response (ABR) monitoring. Thirty-six patients underwent vestibular schwannoma resection via the retrosigmoid approach to preserve hearing. Both CNAP with the microdissector and surface ABR were recorded during the operation. We used the microdissector as an intracranial electrode for CNAP monitoring. The CNAP waveform was classified into four types: triphasic, biphasic, positive, and flat. At the completion of the tumor resection, the triphasic waveform was observed in 11 patients and the biphasic waveform was observed in 11 patients. Hearing function was preserved in all of them, although it was preserved in only two patients with other CNAP waveform types. The prognostic value of CNAP is significantly higher than that of ABR. We found that although CNAP with a microdissector does not provide real-time monitoring, with the classification of waveforms it can be used as predictable tool for postoperative hearing more accurately than ABR