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Despite an increasing number of English-language learners (ELLs) in U.S. schools and a trend toward placing them in mainstream classrooms, relatively little attention has been paid to synthesizing and appraising the extant research on how future mainstream teachers are prepared to teach this student population. To shed light on this topic, the article analyzes the limited but expanding body of research on the preprofessional preparation of mainstream teachers for linguistically diverse classrooms. The authors found that between 2000 and 2018, teacher educators experimented with a variety of pedagogical strategies, most of which situated learning to teach ELLs in diverse classrooms, schools, and communities--both in the United States and elsewhere. The authors conclude that despite having equity goals and including a variety of pedagogically rich ideas for preparing future mainstream teachers to teach ELLs, the vast majority of the studies leave unquestioned the power dynamics that sustain existing educational and social inequalities, thereby perpetuating the status quo.

Focal duodenal necrosis (FDN) is an intestinal disease of egg-layer chickens characterized by multifocal necrosis of the duodenal loop and proximal jejunum. Affected flocks usually have decreased egg weights and drops in egg production. Previous studies have associated this condition with Clostridium perfringens infection. We tried to reproduce FDN by experimental infection of egg-laying chickens using different netB-positive and netB-negative C. perfringens strains, and duodenal homogenate obtained from FDN lesions. Chickens challenged with C. perfringens and/or duodenal homogenate developed duodenitis after challenge. Gross lesions included mucosal erosions, hyperemia, mucosal hemorrhages, and watery intestinal content. Microscopic lesions included mild enterocyte degeneration and necrosis, and mild-to-moderate hemorrhage and lymphoplasmacytic and heterophilic infiltration of the lamina propria. Two netB-positive C. perfringens strains closely related to necrotic enteritis pathogenic strains, by genomic composition, were re-isolated from lesions. Necrosis of intestinal crypts was observed in chickens challenged with duodenal homogenate with or without C. perfringens coinfection. Characteristic microscopic FDN lesions with significant necrosis and loss of villus enterocytes were not reproduced.

Simultaneously recording network activity and ultrastructural changes of the synapse is essential for advancing understanding of the basis of neuronal functions. However, the rapid millisecond‐scale fluctuations in neuronal activity and the subtle sub‐diffraction resolution changes of synaptic morphology pose significant challenges to this endeavor. Here, specially designed graphene microelectrode arrays (G‐MEAs) are used, which are compatible with high spatial resolution imaging across various scales as well as permit high temporal resolution electrophysiological recordings to address these challenges. Furthermore, alongside G‐MEAs, an easy‐to‐implement machine learning algorithm is developed to efficiently process the large datasets collected from MEA recordings. It is demonstrated that the combined use of G‐MEAs, machine learning (ML) spike analysis, and 4D structured illumination microscopy (SIM) enables monitoring the impact of disease progression on hippocampal neurons which are treated with an intracellular cholesterol transport inhibitor mimicking Niemann–Pick disease type C (NPC), and show that synaptic boutons, compared to untreated controls, significantly increase in size, leading to a loss in neuronal signaling capacity. [ABSTRACT FROM AUTHOR]

Drug studies targeting neuronal ion channels are crucial to understand neuronal function and develop therapies for neurological diseases. The traditional method to study neuronal ion‐channel activities heavily relies on the whole‐cell patch clamp as the industry standard. However, this technique is both technically challenging and labour‐intensive, while involving the complexity of keeping cells alive with low throughput. Therefore, the shortcomings are limiting the efficiency of ion‐channel‐related neuroscience research and drug testing. Here, this work reports a new system of integrating neuron membranes with organic microelectrode arrays (OMEAs) for ion‐channel‐related drug studies. This work demonstrates that the supported lipid bilayers (SLBs) derived from both neuron‐like (neuroblastoma) cells and primary neurons are integrated with OMEAs for the first time. The increased expression of voltage‐gated calcium (CaV) ion channels on differentiated SH‐SY5Y SLBs compared to non‐differentiated ones is sensed electrically. Also, dose‐response of the CaV ion‐channel blocking effect on primary cortical neuronal SLBs from rats is monitored. The dose range causing ion channel blocking is comparable to literature. This system overcomes the major challenges from traditional methods (e.g., patch clamp) and showcases an easy‐to‐test, rapid, ultra‐sensitive, cell‐free, and high‐throughput platform to monitor dose‐dependent ion‐channel blocking effects on native neuronal membranes. [ABSTRACT FROM AUTHOR]

This article systematically reviews and critically appraises the research published since 2000 on preparing preservice teachers for English language learners (ELLs). Employing Feiman-Nemser's framework for teacher learning, the authors address what the research suggests about the nature and outcomes of preservice learning opportunities offered to mainstream teachers for teaching ELLs. The review sheds light on how preservice teachers learn to teach ELLs and the learning opportunities they are offered to support this process.

This article argues that research on teacher preparation over the last 100 years can be understood in terms of the major questions that researchers examined. The analysis is guided by the framework of "research as historically situated social practice," which emphasizes that researchers' interests, commitments, and social experiences guide the research questions they pursue and the theories and perspectives they adopt. Past research on initial teacher education is described in terms of the emergence of three broad questions: "the curriculum question," "the effectiveness question," and "the knowledge question." Present research focuses on two broad animating questions: "the policy question" and "the learning question." We recommend that future research address questions that link teacher learning with student learning and teacher candidates' beliefs and practices as well as questions that examine the relationships between research practices and social, economic and institutional power.