Low-Energy Charge-Density Excitations in MgB2_{2}: Striking Interplay between Single-Particle and Collective Behavior for Large Momenta

A sharp feature in the charge-density excitation spectra of single-crystal MgB$_{2}$, displaying a remarkable cosine-like, periodic energy dispersion with momentum transfer ($q$) along the $c^{*}$-axis, has been observed for the first time by high-resolution non-resonant inelastic x-ray scattering (NIXS). Time-dependent density-functional theory calculations show that the physics underlying the NIXS data is strong coupling between single-particle and collective degrees of freedom, mediated by large crystal local-field effects. As a result, the small-$q$ collective mode residing in the single-particle excitation gap of the B $\pi$ bands reappears periodically in higher Brillouin zones. The NIXS data thus embody a novel signature of the layered electronic structure of MgB$_{2}$.Comment: 5 pages, 4 figures, submitted to PR

Stem cells and repair of lung injuries

Fueled by the promise of regenerative medicine, currently there is unprecedented interest in stem cells. Furthermore, there have been revolutionary, but somewhat controversial, advances in our understanding of stem cell biology. Stem cells likely play key roles in the repair of diverse lung injuries. However, due to very low rates of cellular proliferation in vivo in the normal steady state, cellular and architectural complexity of the respiratory tract, and the lack of an intensive research effort, lung stem cells remain poorly understood compared to those in other major organ systems. In the present review, we concisely explore the conceptual framework of stem cell biology and recent advances pertinent to the lungs. We illustrate lung diseases in which manipulation of stem cells may be physiologically significant and highlight the challenges facing stem cell-related therapy in the lung

Medium-term Outcomes of Myocarditis and Pericarditis following BNT162b2 Vaccination among Adolescents in Hong Kong

In this study, we examined the clinical and electrophysiological outcomes of adolescents in Hong Kong who developed myocarditis or pericarditis following BNT162b2 vaccination for COVID-19, and followed-up for 60 to 180 days after their initial diagnosis. Clinical assessments included electrocardiogram (ECG) and echocardiogram at the initial admission and follow-up were compared. Treadmill testing was also performed in some cases. Between 14 June 2021 and 16 February 2022, 53 subjects were approached to participate in this follow-up study, of which 28 patients were followed up for >60 days with a median follow-up period of 100 days (range, 61-178 days) and were included in this study. On admission, 23 patients had ECG abnormalities but no high-grade atrioventricular block. Six patients had echocardiogram abnormalities, including reduced contractility, small rim pericardial effusions, and hyperechoic ventricular walls. All patients achieved complete recovery on follow-up. After discharge, 10 patients (35.7%) reported symptoms, including occasional chest pain, shortness of breath, reduced exercise tolerance, and recurrent vasovagal near-syncope. At follow-up, assessments, including ECGs, were almost all normal. Among the three patients with possible ECG abnormalities, all their echocardiograms or treadmill testings were normal. Sixteen patients (57.1%) underwent treadmill testing at a median of 117 days post-admission, which were also normal. However, at follow-up, there was a significant mean bodyweight increase of 1.81kg (95%CI 0.47-3.1 kg, p=0.01), possibly due to exercise restriction. In conclusion, most adolescents experiencing myocarditis and pericarditis following BNT162b2 vaccination achieved complete recovery. Some patients developed non-specific persistent symptoms, and bodyweight changes shall be monitored

Effects of Instruction in Morphological Awareness on Literacy Achievement: An Integrative Review

As many studies have now demonstrated that morphological awareness contributes to students' literacy development, there is growing interest in the educational value of instruction in morphological awareness. This review was undertaken to integrate findings of studies that sought to determine whether such instruction contributed to improvement in literacy. Analysis of the 16 studies that met selection criteria is organized around researchers' purpose(s) in studying the relation of morphological awareness instruction to key components of literacy development (i.e., phonology, orthography, word meaning). Results indicate that morphological awareness has the potential to contribute to students' literacy development in all three areas—most notably when it deepens students' understanding of the morphemic structure, spelling, and meaning of written words. However, examination of the design and quality of the studies of instruction in morphological awareness suggests that this is an emerging area of research. Much needs to be done to provide a clearer understanding of how, when, and why morphological awareness instruction contributes to students' literacy development. تزايد الاهتمام بالقيمة التعليمية للتدريس في مجال المعرفة الصرفية لأن العديد من الدراسات قد أثبتت الآن أن المعرفة الصرفية تسهم في تطوير القراءة والكتابة بالنسبة للطلاب. لقد تم العمل على هذه المراجعة النقدية لدمج النتاتج التي توصلت إليها الدراسات التي سعت إلى تحديد إن كان هذا التدريس قد أسهم في تحسين القراءة والكتابة. يتمحور تحليل الدراسات الستة عشرة التي تخضع لمعايير الانتقاء حول غرض/ أغراض الباحثين في دراسة العلاقة بين تعليم المعرفة الصرفية والمكونات الرئيسية لتطوير القراءة والكتابة ( أي علم الأصوات الكلامية والإملاء ومعنى الكلمة ). تشير النتائج أن للمعرفة الصرفية قدرة على الاسهام في تطوير القراءة والكتابة بالنسبة للطلاب في المجالات الثلاثة – لاسيما عندما تعمق فهم الطلاب للبنية الصرفية والاملاء وكذلك معنى الكلمات المكتوبة. ومع ذلك فإن دراسة التصميم وجودة دراسات تعليم المعرفة الصرفية توحي بأنها مجال ناشئ للبحث. نحتاج إلى القيام بالكثير من الأبحاث من أجل توفير فهم أوضح عن كيف ومتى ولماذا تسهم المعرفة الصرفية في تطوير القراءة والكتابة لدى الطلاب. 现今许多研究已证明词法意识有助学生的读写能力发展，而人们对词法意识在读写教学方面的教育价值之兴趣也日益俱增。本文献综述旨在结合有关确定词法意识教学对改善读写教学成效之研究结果。本文献综述分析16个符合挑选标准的相关研究进行。分析内容围绕着研究者在考查词法意识教学与读写能力发展的关键组成部分(即语音、拼字法，词义）之关系时所持之研究目的。分析结果显示，词法意识教学有促进学生在这三方面的读写能力发展的潜力，而最显著的是在加深学生对书面字词的语素结构、拼写及单词意义之认识方面的潜力。然而，考查词法意识教学研究之设计与素质结果显示这是一个新兴的研究领域。对于词法意识教学如何、何时及为何有助于学生读写能力发展，仍需要进一步研究， 寻求更清晰的认识。 Du fait que beaucoup d'études ont maintenant fait la preuve que la conscience morphologique contribue au développement de la littératie des élèves, il existe un intérêt croissant à l'égard de l'intérêt pédagogique que présente l'enseignement de la morphologie. Cette revue a été entreprise afin d'intégrer les résultats des études conçues pour déterminer si un tel enseignement contribue au développement de la littératie. L'analyse des seize études répondant aux critères de sélection a été effectuée sur les recherches ayant pour but d'étudier la relation entre l'enseignement de la conscience morphologique et des composants‐clé du développement de la littératie (c'est‐à‐dire la phonologie, l'orthographe, la signification des mots). Les résultats montrent que la conscience morphologique peut contribuer au développement de la littératie des élèves dans les trois domaines — elle permet en particulier d'approfondir la compréhension de la structure morphémique, l'orthographe, et la signification des mots écrits. Cependant, l'examen des plans expérimentaux et la qualité des recherches sur la conscience morphologique suggère qu'il s'agit là d'un secteur émergent de recherche. Il reste beaucoup à faire pour comprendre plus clairement comment, quand, et pourquoi la conscience morphologique contribue au développement de la littératie des élèves. Множество исследований свидетельствуют о том, что для развития грамотности учащихся важно понимание морфологического состава слова, поэтому растет интерес к соответствующим обучающим программам. Данный обзор охватывает результаты шестнадцати исследований, которые помогают определить, какой вклад вносят подобные программы в развитие грамотности. Исследования были проанализированы с точки зрения цели или целей, которые ставили перед собой ученые при изучении морфологического сознания учащихся в контексте общего развития грамотности по ключевым компонентам (фонология, орфография, семантика). Результаты подтверждают, что знание морфологии способно продвинуть учащихся во всех трех компонентах грамотности, поскольку углубляется понимание структуры слов, особенностей их написания и смысла. Однако, экспертиза уже предпринятых исследований показывает, что их качество оставляет желать лучшего и эта работа только начинается. Ученым еще предстоит понять как, когда и почему надо заниматься с учениками морфологией и какое значение имеет морфология для развития грамотности. Ya que muchos estudios han mostrado que la conciencia morfológica contribuye al desarrollo de la alfabetización de los estudiantes, está creciendo el interés en el valor docente de la enseñanza de la conciencia morfológica. Este repaso se ha hecho para integrar las conclusiones de estudios que trataron de determinar si dicha instrucción contribuyó al mejoramiento en la alfabetización. El análisis de los 16 estudios que cumplían los criterios de selección fue organizado de acuerdo a los objetivos de los investigadores para estudiar la relación que la instrucción sobre la conciencia morfológica tiene con los componentes claves del desarrollo de la alfabetización (o sea, la fonología, la ortografía, el significado de palabras). Los resultados indican que la conciencia morfológica tiene el potencial de contribuir al desarrollo de la alfabetización de los estudiantes en las tres áreas—particularmente cuando dicha conciencia profundiza el entendimiento de la estructura del morfema, la ortografía, y el significado de las palabras escritas. Sin embargo, la revisión del diseño y la calidad de los estudios de instrucción sobre la conciencia morfológica sugieren que esta área de investigación está comenzando. Falta mucho por hacer para tener un entendimiento claro de cómo, cuándo y por qué la instrucción sobre la conciencia morfológica contribuye al desarrollo de la alfabetización del estudiante.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/88040/1/RRQ.45.4.5.pd

A Cellular Pathway Involved in Clara Cell to Alveolar Type II Cell Differentiation after Severe Lung Injury

Regeneration of alveolar epithelia following severe pulmonary damage is critical for lung function. We and others have previously shown that Scgb1a1-expressing cells, most likely Clara cells, can give rise to newly generated alveolar type 2 cells (AT2s) in response to severe lung damage induced by either influenza virus infection or bleomycin treatment. In this study, we have investigated cellular pathway underlying the Clara cell to AT2 differentiation. We show that the initial intermediates are bronchiolar epithelial cells that exhibit Clara cell morphology and express Clara cell marker, Scgb1a1, as well as the AT2 cell marker, pro-surfactant protein C (pro-SPC). These cells, referred to as pro-SPC[superscript +] bronchiolar epithelial cells (or SBECs), gradually lose Scgb1a1 expression and give rise to pro-SPC[superscript +] cells in the ring structures in the damaged parenchyma, which appear to differentiate into AT2s via a process sharing some features with that observed during alveolar epithelial development in the embryonic lung. These findings suggest that SBECs are intermediates of Clara cell to AT2 differentiation during the repair of alveolar epithelia following severe pulmonary injury.Singapore-MIT Alliance for Research and Technology Center. Infectious Disease Research Grou

Genetic and Environmental Influences on Chinese Language and Reading Abilities

This study investigated the etiology of individual differences in Chinese language and reading skills in 312 typically developing Chinese twin pairs aged from 3 to 11 years (228 pairs of monozygotic twins and 84 pairs of dizygotic twins; 166 male pairs and 146 female pairs). Children were individually given tasks of Chinese word reading, receptive vocabulary, phonological memory, tone awareness, syllable and rhyme awareness, rapid automatized naming, morphological awareness and orthographic skills, and Raven's Coloured Progressive Matrices. All analyses controlled for the effects of age. There were moderate to substantial genetic influences on word reading, tone awareness, phonological memory, morphological awareness and rapid automatized naming (estimates ranged from .42 to .73), while shared environment exerted moderate to strong effects on receptive vocabulary, syllable and rhyme awareness and orthographic skills (estimates ranged from .35 to .63). Results were largely unchanged when scores were adjusted for nonverbal reasoning as well as age. Findings of this study are mostly similar to those found for English, a language with very different characteristics, and suggest the universality of genetic and environmental influences across languages

Combined effects of a third-generation bisphosphonate, zoledronic acid with other anticancer agents against murine osteosarcoma

Bisphosphonates (BPs) are widely used to treat bone diseases and also appear to possess direct antitumour activity. We have previously reported that third-generation BPs such as zoledronic acid (ZOL) and minodronic acid (YM529) synergistically augment the effects of anticancer agents in various cancer cells. Recently, we have also reported the antitumour effects of YM529 on murine osteosarcoma cells. As YM529 has not been clinically available, we herein focused on the anti-osteosarcoma effects of ZOL which is clinically available. In addition to ZOL alone, we evaluated the concurrent or sequential combined effects of ZOL with other anticancer agents against murine osteosarcoma cell lines. ZOL showed almost same anti-osteosarcoma activity compared with YM529 and more sensitive growth inhibitory effects against osteosarcoma cells than normal cells. Moreover, ZOL acted synergistically in vitro when administered concurrently with paclitaxel (PAC) or gemcitabine (GEM), not only in wild-type osteosarcoma cells but also in P-glycoprotein (P-gp)-overexpressing osteosarcoma cells, which were much less sensitive against each anticancer agent. Furthermore, 24 h of ZOL pretreatment significantly augmented the sensitivity of doxorubicin (DOX), PAC or GEM against osteosarcoma cells. These findings suggest that combined administration of ZOL with other anticancer agents may improve the osteosarcoma treatment

Selective Reduction of Post-Selection CD8 Thymocyte Proliferation in IL-15Rα Deficient Mice

Peripheral CD8+ T cells are defective in both IL-15 and IL-15Rα knock-out (KO) mice; however, whether IL-15/IL-15Rα deficiency has a similar effect on CD8 single-positive (SP) thymocytes remains unclear. In this study, we investigated whether the absence of IL-15 transpresentation in IL-15Rα KO mice results in a defect in thymic CD8 single positive (SP) TCRhi thymocytes. Comparison of CD8SP TCRhi thymocytes from IL-15Rα KO mice with their wild type (WT) counterparts by flow cytometry showed a significant reduction in the percentage of CD69− CD8SP TCRhi thymocytes, which represent thymic premigrants. In addition, analysis of in vivo 5-bromo-2-deoxyuridine (BrdU) incorporation demonstrated that premigrant expansion of CD8SP TCRhi thymocytes was reduced in IL-15Rα KO mice. The presence of IL-15 transpresentation-dependent expansion in CD8SP TCRhi thymocytes was assessed by culturing total thymocytes in IL-15Rα-Fc fusion protein-pre-bound plates that were pre-incubated with IL-15 to mimic IL-15 transpresentation in vitro. The results demonstrated that CD8SP thymocytes selectively outgrew other thymic subsets. The contribution of the newly divided CD8SP thymocytes to the peripheral CD8+ T cell pool was examined using double labeling with intrathymically injected FITC and intravenously injected BrdU. A marked decrease in FITC+ BrdU+ CD8+ T cells was observed in the IL-15Rα KO lymph nodes. Through these experiments, we identified an IL-15 transpresentation-dependent proliferation process selective for the mature CD8SP premigrant subpopulation. Importantly, this process may contribute to the maintenance of the normal peripheral CD8+ T cell pool

CD169(+) macrophages are critical for osteoblast maintenance and promote intramembranous and endochondral ossification during bone repair

Osteal macrophages (osteomacs) contribute to bone homeostasis and regeneration. To further distinguish their functions from osteoclasts, which share many markers and growth factor requirements, we developed a rapid, enzyme-free osteomac enrichment protocol that permitted characterization of minimally manipulated osteomacs by flow cytometry. Osteomacs differ from osteoclasts in expression of Siglec1 (CD169). This distinction was confirmed using the CD169-diphtheria toxin (DT) receptor (DTR) knock-in model. DT treatment of naïve CD169-DTR mice resulted in selective and striking loss of osteomacs, whilst osteoclasts and trabecular bone area were unaffected. Consistent with a previously-reported trophic interaction, osteomac loss was accompanied by a concomitant and proportionately striking reduction in osteoblasts. The impact of CD169 macrophage depletion was assessed in two models of bone injury that heal via either intramembranous (tibial injury) or endochondral (internally-plated femoral fracture model) ossification. In both models, CD169 macrophage, including osteomac depletion compromised bone repair. Importantly, DT treatment in CD169-DTR mice did not affect osteoclast frequency in either model. In the femoral fracture model, the magnitude of callus formation correlated with the number of F4/80 macrophages that persisted within the callus. Overall these observations provide compelling support that CD169 osteomacs, independent of osteoclasts, provide vital pro-anabolic support to osteoblasts during both bone homeostasis and repair