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Titanium nitride (TiN) is an ideal material for infrared plasmonics due to its excellent optical properties, high melting temperature, mechanical and chemical stabilities, and bio- and CMOS compatibilities. In this work, we demonstrate that ultrathin and scalable TiN epitaxial structures can be applied for tunable infrared plasmonics, extending into near- to mid-infrared spectral regions. The ultrathin (111)-oriented TiN epitaxial films studied here were grown on c-plane sapphire wafers without any wetting layer by ultrahigh-vacuum nitrogen-plasma-assisted molecular-beam epitaxy. This method allows for stoichiometric TiN growth without the issue of contamination (especially oxygen) in conventional TiN growth techniques. Structural analyses for these films validate their single-crystalline properties with continuous film morphologies down to a few nanometers in thickness. Furthermore, the frequency-tunable (wavelength range: 1-4 μm) plasmonic metasurfaces have been demonstrated by controlling surface plasmon resonances via lithographically patterning of ultrathin TiN epitaxial films with varying thicknesses (4-30 nm) and grating structure parameters (pitch: 300-1200 nm, width: 200-800 nm). The tunable plasmonic metasurfaces based on ultrathin TiN epitaxial films hold great promise for emerging infrared plasmonic applications, such as thermal photovoltaics requiring narrow-band emitters, photodetectors, and biosensors in the near- and mid-infrared spectral regions.

Fall 2020, COVID-19 restrictions in place on most college campuses may have resulted in the reality of college life not aligning with student expectations. This survey study, conducted at a university in the Midwest, sought to determine the perceptions of first-year college students regarding whether there was a misalignment with their prior expectations and in which areas these misalignments existed, if they did exist. At this university, the COVID-19 restrictions resulted in changes in the delivery formats of courses, and restrictions of social gatherings and on-campus activities. In addition, academic resources such as tutoring, writing center assistance, and study groups were unavailable or curtailed in scope and operating times. This study focused on student perceptions of the impact of course delivery, academics, and social opportunities. The majority of the first-year students in this study reported they were unsure if the restrictions impacted their expectations of what college would be like academically but did report their belief that blended/hybrid courses better supported their learning than either synchronous or asynchronous courses. The largest factor impacting the misalignment of prior student expectations and the Fall 2020 college campus reality was linked to social activities and interactions with 60% of participants listing this as an area where the Fall 2020 college experiences did not meet their expectations.

Taiwan government consolidated the kindergarten and daycare systems in 2012, and launched a new national curriculum framework, Early Childhood Education & Care Curriculum Framework (ECECCF), as a guidance for quality early childhood education programs. Research has shown that the effects of a new educational program highly depended on the fidelity of its implementation. It has thus been suggested that the degree of implantation of a program needs be evaluated before conducting further program evaluation. Thus, the purpose of this study was to construct an Early Childhood Education Curriculum Framework Implementation Scale (ECECCF Implementation Scale) for Taiwanese preschool programs. 216 preschool classes in Taiwan were involved. The study consisted of two stages: In Stage 1, the exploratory factor analysis showed that the implementation of ECECCF could mostly be explained by four factors, and all the factors extracted had acceptable reliability and validity. In Stage 2, rubrics were constructed for each item and factor analysis was re-conducted, resulting in a 19-item scale of four factors (Awareness and Adjustment, Learning Centers Arrangement, Teaching Guidance and Curriculum Development). The reliability and validity tests shows that: (1) the final version of the ECECCF Implementation Scale is a valid and reliable instrument, explaining 62.9% of the total variance; (2) the criterion validity indicated that the ECECCF scale can not only be used for assessing the implementation of ECECCF, but also can be used for understanding teachers' needs in instructional and operational curriculum for further professional development.

The focus of this study was to evaluate the use of the Blackboard™ App by students in traditional and online learning environments. The participants in this study were students in a first-year college orientation course, and undergraduate and graduate students enrolled in educational technology (EDT) courses, all at a 4-year public university in the Midwest. The orientation course is a traditional seated class with the Blackboard Learn™ learning management system supplementing the face-to-face instruction; the graduate and undergraduate EDT courses are all fully online, taught through Blackboard Learn. The study compared whether students prefer the Blackboard App over the use of email for communicating with their instructors. Descriptive statistics were used to analyze the survey response data. Students' positive responses concerning the Blackboard app and their preference for email were summarized and discussed.

Accreditation serves many constituents and for a variety of reasons. It attempts to attest to the quality of a particular program that in most cases prepares people to enter a specific job or profession. The study examined faculty perceptions of the CAEP process in accrediting their teacher education programs and the impact on resources including human resources and morale. Through a researcher-constructed survey and then focused interviews, educators at this university indicated they believed the process of national accreditation was important for enhanced status and prestige, but questioned whether it helped with needed systemic changes. They also noted that faculty workload was a drawback unless faculty were recognized for their work. Conclusions to the study offered three recommendations: (1) faculty along with other key stakeholders should have a strong voice in the decision to pursue accreditation; (2) personnel need to be appreciated for their intensive work; and (3) institutions need to allocate adequate and realistic resources for the entire process. Additionally, universities need to use the lessons learned and outcomes of the process to strengthen and change programs and policies when necessary for continuous improvement.

Nematode-trapping fungi (NTF) are a group of specialized microbial predators that consume nematodes when food sources are limited. Predation is initiated when conserved nematode ascaroside pheromones are sensed, followed by the development of complex trapping devices. To gain insights into the coevolution of this interkingdom predator-prey relationship, we investigated natural populations of nematodes and NTF that we found to be ubiquitous in soils. Arthrobotrys species were sympatric with various nematode species and behaved as generalist predators. The ability to sense prey among wild isolates of Arthrobotrys oligospora varied greatly, as determined by the number of traps after exposure to Caenorhabditis elegans While some strains were highly sensitive to C. elegans and the nematode pheromone ascarosides, others responded only weakly. Furthermore, strains that were highly sensitive to the nematode prey also developed traps faster. The polymorphic nature of trap formation correlated with competency in prey killing, as well as with the phylogeny of A. oligospora natural strains, calculated after assembly and annotation of the genomes of 20 isolates. A chromosome-level genome assembly and annotation were established for one of the most sensitive wild isolates, and deletion of the only G-protein β-subunit-encoding gene of A. oligospora nearly abolished trap formation. In summary, our study establishes a highly responsive A. oligospora wild isolate as a model strain for the study of fungus-nematode interactions and demonstrates that trap formation is a fitness character in generalist predators of the nematode-trapping fungus family.

Electronic communication is the standard method of communication among college students. However, which format of e-communication is most preferred seems to be somewhat of a moving target. Utilizing a researcher-developed survey, this study investigated the use of Remind, a popular form of instant messaging, for communication between the instructors and students in two sections of a required, first-year college orientation course. The use of this instant messaging platform was compared to the use of email. Two research questions drove this study. When asked whether instant message-based course communication was more effective than email communication, 75.4% of participants agreed, with 61.5% reacting to information in Remind more quickly than messages via email. Information from the second question showed 94% of participants felt Remind helped them organize their learning. Overall, the responses to the use of Remind were positive, and it was clearly preferred over traditional email communication for a number of reasons delineated in the study. Actual participant comments are included.

As enrollment in distance education courses continues to increase, it is clear that online course delivery is here to stay. And all online courses today utilize a web- or cloud-based Learning Management System that includes a text-based discussion forum, commonly called a 'discussion board', which is the primary mode of communication within the course site. This study investigates the use of voice-based technology as an alternative to typing in text for submitting discussion posts. An 18-question survey was administered to in-service and pre-service teachers enrolled in two online graduate educational technology courses. The results were somewhat mixed, but overall, the participants provided positive feedback when utilizing a voice-based application to complete online class discussions. Ninety-four percent of the participants had never used the voice-based application before, which likely accounted for some portion of the less-than-positive feedback.

An increasing body of evidence points to significant spatio-temporal differences in early placental development between mouse and human, but a detailed comparison of placentae in these two species is missing. We set out to compare placentae from both species across gestation, with a focus on trophoblast progenitor markers. We found that CDX2 and ELF5, but not EOMES, are expressed in early post-implantation trophoblast subpopulations in both species. Genome-wide expression profiling of mouse and human placentae revealed clusters of genes with distinct co-expression patterns across gestation. Overall, there was a closer fit between patterns observed in the placentae when the inter-species comparison was restricted to human placentae through gestational week 16 (thus, excluding full-term samples), suggesting that the developmental timeline in mouse runs parallel to the first half of human placental development. In addition, we identified VGLL1 as a human-specific marker of proliferative cytotrophoblast, where it is co-expressed with the transcription factor TEAD4. As TEAD4 is involved in trophectoderm specification in the mouse, we posit a regulatory role for VGLL1 in early events during human placental development.

Development of the early embryo takes place under low oxygen tension. Under such conditions, the embryo implants and the trophectoderm, the outer layer of blastocyst, proliferate, forming the cytotrophoblastic shell, the early placenta. The cytotrophoblasts (CTBs) are the so-called epithelial 'stem cells' of the placenta, which, depending on the signals they receive, can differentiate into either extravillous trophoblast (EVT) or syncytiotrophoblast (STB). EVTs anchor the placenta to the uterine wall and remodel maternal spiral arterioles in order to provide ample blood supply to the growing fetus. STBs arise through CTB fusion, secrete hormones necessary for pregnancy maintenance and form a barrier across which nutrient and gas exchange can take place. The bulk of EVT differentiation occurs during the first trimester, before the onset of maternal arterial blood flow into the intervillous space of the placenta, and thus under low oxygen tension. These conditions affect numerous signaling pathways, including those acting through hypoxia-inducible factor, the nutrient sensor mTOR and the endoplasmic reticulum stress-induced unfolded protein response pathway. These pathways are known to be involved in placental development and disease, and specific components have even been identified as directly involved in lineage-specific trophoblast differentiation. Nevertheless, much controversy surrounds the role of hypoxia in trophoblast differentiation, particularly with EVT. This review summarizes previous studies on this topic, with the intent of integrating these results and synthesizing conclusions that resolve some of the controversy, but then also pointing to remaining areas, which require further investigation.

Abnormal trophoblast differentiation is the root cause of many placenta-based pregnancy complications, including preeclampsia and fetal growth restriction. Human trophoblast differentiation is difficult to study due to the lack of a stem cell model. Such a multipotent "trophoblast stem" (TS) cell, with the ability to differentiate into all trophoblast subtypes, has been derived from mouse blastocysts, but attempts to derive similar human cells have failed. We consider here several possibilities for the TS cell niche in the human placenta. Aside from discussion of such a niche in the pre-implantation blastocyst, we discuss evidence for these TS cells residing in the post-implantation villous cytotrophoblast layer, or even in the non-trophoblast portions, of the human placenta. It is our hope that recognition of the niche would lead to successful derivation and in vitro establishment of such cells, which could then be disseminated widely to the placental biology community for advancing the field. Availability of self-renewing human TS cells, whose gene expression and environment could be manipulated, will provide a platform, not just for the study of pathophysiology of placental disease, but also for the discovery of diagnostic biomarkers and therapeutic targets for common pregnancy complications.

Villous cytotrophoblasts are epithelial stem cells of the early human placenta, able to differentiate either into syncytiotrophoblasts in floating chorionic villi or extravillous trophoblasts (EVTs) at the anchoring villi. The signaling pathways regulating differentiation into these two lineages are incompletely understood. The bulk of placental growth and development in the first trimester occurs under low oxygen tension. One major mechanism by which oxygen regulates cellular function is through the hypoxia-inducible factor (HIF), a transcription factor complex stabilized under low oxygen tension to mediate cellular responses, including cell fate decisions. HIF is known to play a role in trophoblast differentiation in rodents; however, its role in human trophoblast differentiation is poorly understood. Using RNA profiling of sorted populations of primary first-trimester trophoblasts, we evaluated the first stage of EVT differentiation, the transition from epidermal growth factor receptor+ villous cytotrophoblasts into human leukocyte antigen-G+ proximal column EVT (pcEVT) and identified hypoxia as a major pcEVT-associated pathway. Using primary cytotrophoblasts, we determined that culture in low oxygen directs differentiation preferentially toward human leukocyte antigen-G+ pcEVT, and that an intact HIF complex is required for this process. Finally, using global RNA profiling, we identified integrin-linked kinase and associated cytoskeletal remodeling and adhesion to be among HIF-dependent pcEVT-associated signaling pathways. Taken together, we propose that oxygen regulates EVT differentiation through HIF-dependent modulation of various cell adhesion and morphology-related pathways.

Language laboratories, developed in the 1970s under the influence of the Audiolingual Method, were superseded several decades later by computer-assisted language learning (CALL) work stations (Gündüz, 2005). The World Wide Web was developed shortly thereafter. From this introduction and the well-documented and staggering growth of the Internet and WWW, it is clear that the use of web-based instructional technology tools will continue to proliferate. Their use in foreign language or English as a Second/Foreign Language (ESL/EFL) instruction is no exception. Simon (2008) tells us "… many Web 2.0 applications are powerful socialization and communication tools. As such, they will have an incredible educational potential for foreign language instruction." This article provides a discussion of several of the most widely used Web 2.0 tools by K-12 foreign language teachers, ESL/EFL teachers, and higher education language departments. These tools continue to influence how today's educators perceive, define, and teach second language acquisition.

Educators are continuously looking at innovative ways to teaching and working with students of all ages. The tools used range from the simplest technologies, such as chalk and pencils, to the high-tech tools involving computers and information systems. The best tools and strategies often invoke the use of the old and new or the old in a new way. In 2002 an interest in labyrinths (the old) led most naturally to an Internet search (the new) and resulted in the obvious question of how these mysterious, yet marvelous, patterns could be applied to the instructional arena. An extensive search of the traditional literature databases and the Internet at that time revealed only passing comments and anecdotal records and there were few of those. The existing literature did reveal that these mystifying geometric forms have a long history. Curiosity was piqued and enthusiasm ignited as questions centering on how these may relate to children in an educational setting came to the surface. Courses such as "Classroom Management" that, of course, include student behavior, became a consideration. What if a simple geometric tool, such as the labyrinth, could positively affect student behavior and the overall climate in the classroom? Schools create a community in which effective teaching and learning occur. Teachers should care about students' personal, emotional, and spiritual well being besides delivering knowledge. It is important that students are exposed to learning in a climate that nurtures their development in all ways. Could labyrinths help students look inside their minds and explore their potential? The students themselves have some of the answers. As one said, "It gave me a chance to reflect on the things I've done, said and felt." (LECT, 2003) This article will look at the historical background of the labyrinth as well as definitions. Then a modern view will be given with details on the various ways it is being used today including an overview of a school study. Finally, some questions for the future will be raised.