Heme, released from red blood cells in sickle cell disease (SCD), interacts with toll-like receptor 4 (TLR4) to activate NF-κB leading to the production of cytokines and adhesion molecules which promote inflammation, pain, and vaso-occlusion. In SCD, TLR4 inhibition has been shown to modulate heme-induced microvascular stasis and lung injury. We sought to delineate the role of endothelial verses hematopoietic TLR4 in SCD by developing a TLR4 null transgenic sickle mouse. We bred a global Tlr4-/- deficiency state into Townes-AA mice expressing normal human adult hemoglobin A and Townes-SS mice expressing sickle hemoglobin S. SS-Tlr4-/- had similar complete blood counts and serum chemistries as SS-Tlr4+/+ mice. However, SS-Tlr4-/- mice developed significantly less microvascular stasis in dorsal skin fold chambers than SS-Tlr4+/+ mice in response to challenges with heme, lipopolysaccharide (LPS), and hypoxia/reoxygenation (H/R). To define a potential mechanism for decreased microvascular stasis in SS-Tlr4-/- mice, we measured pro-inflammatory NF-κB and adhesion molecules in livers post-heme challenge. Compared to heme-challenged SS-Tlr4+/+ livers, SS-Tlr4-/- livers had lower adhesion molecule and cytokine mRNAs, NF-κB phospho-p65, and adhesion molecule protein expression. Furthermore, lung P-selectin and von Willebrand factor immunostaining was reduced. Next, to establish if endothelial or hematopoietic cell TLR4 signaling is critical to vaso-occlusive physiology, we created chimeric mice by transplanting SS-Tlr4-/- or SS-Tlr4+/+ bone marrow into AA-Tlr4-/- or AA-Tlr4+/+ recipients. Hemin-stimulated microvascular stasis was significantly decreased when the recipient was AA-Tlr4-/-. These data demonstrate that endothelial, but not hematopoietic, TLR4 expression is necessary to initiate vaso-occlusive physiology in SS mice.
Writing has been considered as a highly demanding skill and a complex recursive process involving multifaceted knowledge (e.g. grammar, genre, vocabulary and metacognitive competencies). Hence, it has been documented in miscellaneous studies in the past few decades. However, the issue of challenges and solutions to teaching English writing to junior high school students remains under-researched. Therefore, this study addressed this issue, notably in Indonesian EFL context. Three English teachers from a junior high school in Tasikmalaya, West Java, Indonesia were recruited as the participants. The data were collected through semi-structured interviews and analysed with Thematic Analysis (TA) (Braun & Clarke, 2006). On the one hand, the findings reported that there were seven challenges encountered by teachers when teaching English writing, namely (1) students' poor English grammatical competence, (2) students' incapability of developing ideas for English writing, (3) students' inadequate English vocabulary knowledge, (4) students' demotivation to learn English writing, (5) insufficient time management to teach English writing, (6) limited sources of English writing materials and (7) limited facilities to teach English writing. On the other hand, teachers promoted several solutions to cope with such challenges, namely (1) explicit teaching English vocabulary, (2) collaborative English writing activities, and (3) exercises of English writing. Pedagogically speaking, this study offers practical contributions for the TESOL practitioners to teach English writing effectively to junior high school students, particularly in the Indonesian EFL landscape.
English grammar has a pivotal position in language learning. It is also considered the basis of a series of language skills (listening, speaking, reading, and writing). However, although previous studies focused on teaching English grammar either from a traditional or functional view, where English as L1 and L2 across various educational levels, scarce studies have emphasized teaching English Grammar in the Indonesian EFL context, particularly in Junior High School. Hence, this study aimed at filling such a void, namely teaching English grammar in an Indonesian junior high school. In an attempt for collecting the data, this study interviewed a participant in one of the junior high schools in Tasikmalaya, West Java, Indonesia. The data were analyzed using thematic analysis (Braun Clarke, 2006). The findings of this study revealed that the teacher use focus on forms and focus on form in teaching English grammar. Those focus on forms involve (1) Deductive English Teaching Grammar, (2) Score-Oriented English Language Learning Activities, and (3) Accuracy-Oriented English Language Learning Activities. Another approach is focus on form include (1) Task-Based Sentence Making and (2) Contextual Teaching of English Grammar. By knowing these teaching techniques, the teachers are expected to be able to implement those teaching techniques of teaching English grammar to junior high school students more effectively.
The Covid-19 pandemic has influenced various dimensions of higher education systems globally, including English language learning. To illustrate, the pedagogical practices should be altered from face-to-face to online modes. This move affects students' learning engagement, notably cognitive engagement. Although myriad studies have focused on probing students' cognitive engagement, little is known about how students engage cognitively during emergency remote teaching (ERT). To fill this void, this study investigated students' cognitive engagement in English language learning activities in an ERT environment. Sixty students from three Indonesian higher educational institutions were involved as participants. The data were collected through a semi-structured interview and analyzed with thematic analysis (Braun & Clarke, 2006). The findings revealed that students, (1) deploying metacognitive language learning strategies, (2) possessing self-regulated learning, (3) designating English language learning motivation, (4) showcasing critical thinking as a manifestation of students’ cognitive engagement, and (5) connecting teaching materials to the students’ daily life. The implications of this study call for emphasizing students’ English language learning needs and teachers’ continuous professional development.
This study focused on how teachers and students as the social actors in an Intercultural Communication (IC) classroom were represented discursively. A video recording transcript of IC classroom activities at a state University in Indonesia was selected as the data source. The data source was rigorously analysed through van Leeuwen’s Socio-semantic inventory of social actors framework (Van Leeuwen, 1996). The main findings show that social actors in IC classroom can be categorised into two main thematic representations, namely positive and negative ones. disclosed that Hamzah as the representative of classroom presenters was represented as victimised, oppressed, intimidated and minoritised actor. Hamzah’s Mathematics teacher was depicted as an intolerant, dehumanising, discriminatory and oppressing actor. Hamzah’s Social Sciences teacher was illustrated as a racial, stereotyping, dominant and provoking actor. The Intercultural Communication teacher was delineated as the actor endeavoring to encourage his students to be tolerant, critical, supportive and open-minded people. Hamzah’s classmates in IC classroom were characterised as sympathetic, supportive, friendly and reactionary actors.
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