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The proliferation of educational technologies has had a profound impact on the dynamics of education and has raised questions regarding how the nature of teaching and learning should be conceptualized. This study explores how the use of technology mediates class interaction, shapes class discourse, and supports the English learners' language development. This study's findings show that technology worked as a mediational tool in the classroom to influence class interactions and student learning experience. The study also draws our attention to the important role of the teacher in orchestrating multimodal interactions and providing learners with clear intentions of multiple modes and with necessary linguistic scaffolding, suggesting that teachers should be mindful of the role that social interactions play in achieving an intended pedagogical purpose with the use of computer tools.

Effectively exploring the efficacy of synchronous computer-mediated communication (SCMC) for pedagogical purposes can be achieved through the careful investigation of potentially beneficial, inherent attributes of SCMC. This study provides empirical evidence for the capacity of task-based SCMC to draw learner attention to linguistic forms by offering opportunities for corrective feedback and incidental recasts, highlighting learners' errors. The findings open up the discussion on the meaning of feedback considering learners' perceptions and the unique SCMC features. The findings indicate that learners do not attend to corrective feedback that promote "the corrector" and "the corrected" relationships. Rather, they benefit from incidental recasts that coincidentally contrast with their ill-formed L2 production. This study also challenges the previous assumptions regarding certain SCMC features believed to be beneficial to learners. Features like split turns increase learners' cognitive load and make it difficult for learners to follow the flow of the conversation. Considering split turns of SCMC and learners' different perceptions on tasks, this study calls for reframing recasts in SCMC and more sensitive research methods for investigating SCMC interaction.

The growing population of young English language learners (ELLs) in American schools creates an urgency for educators to understand, value, and support the wide array of students' native language practices as a way to support both the ELLs' first language and their native cultures and communities. Considerable research shows the importance of first language (L1) education in the development of ELL identity. This includes access to community resources and English language development. To support L1 education at home, parents first need to believe in the value of the L1 home language and its corresponding culture and then they must be informed about how to support it. Very few studies exist either on parents' beliefs about the role of their home language in their children's education, or on how to support such language learning at home. This study examines ELLs' parents' beliefs about L1 education and their home language literacy education practices. These beliefs and practices are then linked to the development of ELL identity and language skills and show how families are affected differently across households. (Contains 1 table and 1 note.)

An essential component for assessing the accuracy and fluency of language learners is understanding how mode of communication and task type affect performance in second-language (L2) acquisition. This study investigates how text-based synchronous computer-mediated communication (SCMC) and face-to-face (F2F) oral interaction can influence the performance of language learners in producing grammatical forms accurately when learners of English as a second language complete different tasks in their L2. Findings show a systematic variability in learner interlanguage that depends on mode of communication and task type. L2 learners used articles more correctly and produced advanced-stage questions more frequently in text-based SCMC than in F2F. These findings suggest that task types and the mode of communication in which a task is completed need careful selection based on pedagogical purposes in order to maximize L2 learning and better evaluate L2 performance.

This study investigated how synchronous computer-mediated communication (SCMC) and face-to-face (F2F) oral interaction influence the way in which learners collaborate in language learning and how they solve their communicative problems. The findings suggest that output modality may affect how learners produce language, attend to linguistic forms, and solve communicative problems. In particular, the use of collaborative processes to construct utterances was more prevalent in F2F interaction than in SCMC. Moreover, learners engaged in activities and produced language differently depending on output modalities, which differed in terms of the physical, social, and interactional contexts that they created and the way in which they influenced learners' communication strategies. The findings indicate that SCMC should be used selectively according to the pedagogical purpose.

This study explores the factors that cause international graduate students to struggle and these students' ways of dealing with such problems in light of sociocultural theory, which views learning as a social and cultural act. The findings show that graduate classes function as communities of practices in which classmates and professors mutually engage with each other, share a repertoire and engage in joint enterprises. The practices were not always transparent to international students, which became a source of difficulty and often led them to feel excluded. Peripheral participation comprised a significant part of some students' learning process and identity formation, but it allowed them to participate in course-related activities as fully as they felt comfortable doing. This study suggests a need for more sensitive and dialogical efforts by educators in higher education to provide better learning environments for international learners.

Noninvasive detection of both early pancreatic neoplasia and metastases could enhance strategies to improve patient survival in this disease that is notorious for an extremely poor prognosis. There are almost no identifiable targets for non-invasive diagnosis by positron emission tomography (PET) for patients with pancreatic ductal adenocarcinoma (PDAC). Over-expression of the receptor for advanced glycation end products (RAGE) is found on the cell surface of both pre-neoplastic lesions and invasive PDAC. Here, a RAGE-specific single chain (scFv) was developed, specific for PET imaging in syngeneic mouse models of PDAC. An anti-RAGE scFv conjugated with a sulfo-Cy5 fluorescence molecule showed high affinity and selectivity for RAGE expressing pancreatic tumor cells and genetically engineered KRASG12D mouse models of PDAC. An in vivo biodistribution study was performed with the 64Cu-radiolabled scFv in a syngeneic murine pancreatic cancer model, demonstrating both the feasibility and potential of an anti-RAGE scFv for detection of PDAC. These studies hold great promise for translation into the clinic. [ABSTRACT FROM AUTHOR]

Fluorescence imaging is a powerful technique with diverse applications in intraoperative settings. Visualization of three dimensional (3D) structures and depth assessment of lesions, however, are oftentimes limited in planar fluorescence imaging systems. In this study, a novel Fluorescence Imaging Topography Scanning (FITS) system has been developed, which offers color reflectance imaging, fluorescence imaging and surface topography scanning capabilities. The system is compact and portable, and thus suitable for deployment in the operating room without disturbing the surgical flow. For system performance, parameters including near infrared fluorescence detection limit, contrast transfer functions and topography depth resolution were characterized. The developed system was tested in chicken tissues ex vivo with simulated tumors for intraoperative imaging. We subsequently conducted in vivo multimodal imaging of sentinel lymph nodes in mice using FITS and PET/CT. The PET/CT/optical multimodal images were co-registered and conveniently presented to users to guide surgeries. Our results show that the developed system can facilitate multimodal intraoperative imaging. [ABSTRACT FROM AUTHOR]

ObjectivesThis study evaluated the objective response to and toxicity of trans-arterial chemo-embolisation (TACE) followed by radiotherapy and hyperthermia (CERT) in hepatocellular carcinoma patients with portal vein tumour thrombosis.MethodsThe study design was a single-centre prospective phase II trial. Patients were first treated with TACE, with the first hyperthermia session 1 week later. Respiration-gated radiotherapy (RT) was delivered in 10 fractions of 3–5 Gy after another week. Six sessions of hyperthermia were delivered twice a week according to an energy escalation protocol. Response evaluation was planned at 1 month after RT completion using the modified Response Evaluation Criteria in Solid Tumors (RECIST). Toxicity was determined using the Common Terminology Criteria for Adverse Events (CTCAE) version 4.0.ResultsInterim analysis was conducted on patients enrolled from October 2013 to November 2014. During this period, 46 patients (90.2%) who received at least one hyperthermia session were eligible and enrolled. Median follow-up was 6.7 months (range 2.0–15.0 months). Complete response was observed in 10 (21.7%) patients and partial response in 27 (47.8%). Most toxicities were grade I or II. One death was related to severe pneumonia of unknown cause in the left lung and one patient could not complete planned treatment because of continuous elevation of bilirubin after TACE. Late, asymptomatic gastroduodenal toxicities were noticed in 13 (28.3%) patients.ConclusionPreliminary evaluation of CERT showed a promising response rate with acceptable toxicities. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study is to investigate the use of mixture of BaSO4 and biodegradable polymer as an injectable nonmetallic fiducial marker to reduce artifacts in x-ray images, decrease the absorbed dose distortion in proton therapy, and replace permanent metal markers. Methods: Two samples were made with 90 wt. % polymer phosphate buffer saline (PBS) and 10 wt. % BaSO4 (B1) or 20 wt. % BaSO4 (B2). Two animal models (mice and rats) were used. To test the injectability and in vivo gelation, a volume of 200 ¡A at a pH 5.8 were injected into the Sprague-Dawley rats. After sacrificing the rats over time, the authors checked the gel morphology. Detectability of the markers in the x-ray images was tested for two sizes (diameters of 1 and 2 mm) for B1 and B2. Four samples were injected into BALB/C mice. The polymer mixed with BaSO4 transform from SOL at 20 °C with a pH of 6.0 to GEL in the living body at 37 °C with a pH of 7.4, so the size of the fiducial marker could be controlled by adjusting the injected volume. The detectability of the BaSO4 marker was measured in x-ray images of cone beam CT (CBCT), on-board imager [anterior-posterior (AP), lateral], and fluoroscopy (AP, lateral) using a Novalis-TX (Varian Medical Systems, Palo Alto, CA) repeatedly over 4 months. The volume, HU, and artifacts for the markers were measured in the CBCT images. Artifacts were compared to those of gold marker by analyzing the HU distribution. The dose distortion in proton therapy was computed by using a Monte Carlo (MC) code. A cylindrical shaped marker (diameter: 1 or 2 mm, length: 3 mm) made of gold, stainless-steel [304], titanium, and 20 wt. % BaSO4 was positioned at the center of the spread-out Bragg peak (SOBP) in parallel or perpendicular to the beam entrance. The dose distortion was measured on the depth dose profile across the markers. Results: Transformation to GEL and the biodegradation were verified. All BaSO4 markers could be detected in the CBCT. In the OBI and fluoroscopy images, all markers visible in the AP, but only B2(2 mm) could be identified in the lateral images. Changes of BaSO4 position were not detected in vivo (mice). The volume of the markers decreased by up to 65% and the HU increased by 22%, on average. The mean HU values around the B1, B2, and gold markers were 121.30 [standard deviation (SD): 54.86], 126.31 (SD: 62.13), and 1070.7 (SD: 235.16), respectively. The MC-simulated dose distortion for the BaSO4 markers was less than that of the commercially used markers. The dose reduction due to the gold marker was largest (15.05%) followed by stainless steel (7.92%) and titanium (6.92%). Dose reduction by B2 (2 mm) was 4.75% and 0.53% in parallel and perpendicular orientations, respectively. Conclusions: BaSO4 mixed with PBS is a good contrast agent in biodegradable polymer marker because of minimal artifacts in x-ray images and minimal dose reduction in proton therapy. The flexibility of the size is considered to be an advantage of this material over solid type fiducials. [ABSTRACT FROM AUTHOR]

Abstract: Cyclodextrin (CD) is a well known drug carrier and excipient for enhancing aqueous solubility. CDs themselves are anticipated to have low membrane permeability because of relatively high hydrophilicity and molecular weight. CD derivatization with 17-beta estradiol (E2) was explored extensively using a number of different click chemistries and the cell membrane permeability of synthetic CD–E2 conjugate was explored by cell reporter assays and confocal fluorescence microscopy. In simile with reported dendrimer–E2 conjugates, CD–E2 was found to be a stable, extranuclear receptor selective estrogen that penetrated into the cytoplasm. [Copyright &y& Elsevier]

Matrix metalloproteinases (MMPs) are involved in tissue remodeling. Accordingly, MMP inhibitors and related radiolabeled analogs are important tools for MMP-targeted imaging and therapy in a number of diseases. Herein, we report design, synthesis, and evaluation of a new Arginine-containing macrocyclic hydroxamate analog, RYM, its hydrazinonicotinamide conjugate, RYM1 and 99mTc-labeled analog 99mTc-RYM1 for molecular imaging. RYM exhibited potent inhibition against a panel of recombinant human (rh) MMPs in vitro. RYM1 was efficiently labeled with 99mTcO4− to give 99mTc-RYM1 in a high radiochemical yield and high radiochemical purity. RYM1 and its decayed labeling product displayed similar inhibition potencies against rhMMP-12. Furthermore, 99mTc-RYM1 exhibited specific binding with lung tissue from lung-specific interleukin-13 transgenic mice, in which MMP activity is increased in conjunction with tissue remodeling and inflammation. The results support further development of such new water-soluble Arginine-containing macrocyclic hydroxamate MMP inhibitors for targeted imaging and therapy. [ABSTRACT FROM AUTHOR]

Matrix metalloproteinase (MMP)-12 plays a key role in the development of aneurysm. Like other members of MMP family, MMP-12 is produced as a proenzyme, mainly by macrophages, and undergoes proteolytic activation to generate an active form. Accordingly, molecular imaging of the MMP-12 active form can inform of the pathogenic process in aneurysm. Here, we developed a novel family of fluorescent probes based on a selective MMP-12 inhibitor, RXP470.1 to target the active form of MMP-12. These probes were stable in complex media and retained the high affinity and selectivity of RXP470.1 for MMP-12. Amongst these, probe 3 containing a zwitterionic fluorophore, ZW800-1, combined a favorable affinity profile toward MMP-12 and faster blood clearance. In vivo binding of probe 3 was observed in murine models of sterile inflammation and carotid aneurysm. Binding specificity was demonstrated using a non-binding homolog. Co-immunostaining localized MMP-12 probe binding to MMP-12 positive areas and F4/80 positive macrophages in aneurysm. In conclusion, the active form of MMP-12 can be detected by optical imaging using RXP470.1-based probes. This is a valuable adjunct for pathophysiology research, drug development, and potentially clinical applications. [ABSTRACT FROM AUTHOR]