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The purpose of this study is to understand how preservice teachers (PTs) learn about disciplinary literacy in English language arts (ELA). In mathematics and writing, research has found that teachers’ participation in disciplinary work can support their understanding of domain-specific inquiry, problem-solving and argumentation.

This exploratory, qualitative case study of an English methods course extends that work into ELA, asking how PTs’ participation in collaborative literary reasoning (CLR) influences their understanding of ELA as a discipline and their instructional planning processes.

Findings indicate that CLR supported PTs to define ELA as a collaborative discipline in which multiple interpretations of literature are valued; to name specific disciplinary literacy practices; to identify a focus and purpose for teachers’ design and revision of lesson plans; and to inform their thinking about text selection and complexity.

This work highlights the potential of collaborative literary reasoning to support PTs’ learning about disciplinary literacy instruction.

Surface quality and porosity significantly influence the structural and functional properties of the final product. This study aims to establish and explain the underlying relationships among processing parameters, top surface roughness and porosity level in additively manufactured 316L stainless steel.

A systematic variation of printing process parameters was conducted to print cubic samples based on laser power, speed and their combinations of energy density. Melt pool morphologies and dimensions, surface roughness quantified by arithmetic mean height (Sa) and porosity levels were characterized via optical confocal microscopy.

The study reveals that the laser power required to achieve optimal top surface quality increases with the volumetric energy density (VED) levels. A smooth top surface (Sa < 15 µm) or a rough surface with humps at high VEDs (VED > 133.3 J/mm³) can serve as indicators for fully dense bulk samples, while rough top surfaces resulting from melt pool discontinuity correlate with high porosity levels. Under insufficient VED, melt pool discontinuity dominates the top surface. At high VEDs, surface quality improves with increased power as mitigation of melt pool discontinuity, followed by the deterioration with hump formation.

This study reveals and summarizes the formation mechanism of dominant features on top surface features and offers a potential method to predict the porosity by observing the top surface features with consideration of processing conditions.

This paper aims to derive a reduced-order model for the heat transfer across the interface between a millimetric thermocapillary liquid bridge from silicone oil and the surrounding ambient gas.

Numerical solutions for the two-fluid model are computed covering a wide parametric space, making a total of 2,800 numerical flow simulations. Based on the computed data, a reduced single-fluid model for the liquid phase is devised, in which the heat transfer between the liquid and the gas is modeled by Newton’s heat transfer law, albeit with a space-dependent Biot function Bi(z), instead of a constant Biot number Bi.

An explicit robust fit of Bi(z) is obtained covering the whole range of parameters considered. The single-fluid model together with the Biot function derived yields very accurate results at much lesser computational cost than the corresponding two-phase fully-coupled simulation required for the two-fluid model.

Using this novel Biot function approach instead of a constant Biot number, the critical Reynolds number can be predicted much more accurately within single-phase linear stability solvers.

The Biot function for thermocapillary liquid bridges is derived from the full multiphase problem by a robust multi-stage fit procedure. The derived Biot function reproduces very well the theoretical boundary layer scalings.

This paper aims to present a robust method for the determination of α- and ß-2, 7, 11-cembratriene-4, 6-diols (α, ß-CBT-diol) in tobacco samples which was developed and validated by using the self-made α, ß-CBT-diol with higher purity as the standard.

After the ultrasonic extraction and clean-up procedures, samples were analyzed by gas chromatography/mass spectrometry in selected ion monitoring mode and full scan mode at the same time. A 1-heptadecanol was used as an internal standard. The important parameters, such as extraction conditions and derivation conditions, were optimized.

Under the optimal conditions, good results in terms of linearity (R² > 0.999) and recoveries (93.2-107 per cent) were achieved. The limits of detection were 0.120 and 0.180 μg/ml for α- and ß-CBT-diol, respectively. α, ß-CBT-diol level of analyzed tobacco was found in the range of 34.2-1.26 × 103 μg/g with relative standard deviations below 6 per cent.

Such a strategy opens a new door towards the development of a simple, robust and sensitive method for the determination of α, ß-CBT-diol in real samples.

To investigate the effect of laser densification parameters on the cross section geometry of the laser‐densified single line, and thus provide guidance for selecting the laser processing condition to obtain dense shapes with minimum processing defects.

A range of dental porcelain powder lines with small cross section areas (in the order of 1 × 1 mm²) were extruded from micro‐extruders and laser densified with the systematically changed peak laser power intensity, laser beam diameter, and ratio of the laser beam diameter to the width of the powder line.

The peak laser power intensity, laser beam diameter, and ratio of the laser beam diameter to the width of the powder line have substantial influence on the cross section geometry. The effects of these laser processing parameters can be explained in terms of minimization of surface energy in both solid and liquid states, volume shrinkage associated with densification, and temperature gradients present in the powder line during laser densification.

For the first time the cross section geometry of single powder lines in response to laser processing conditions has been systematically investigated, and the result offers guidance for obtaining dense shapes with minimum processing defects.

To identify the effects of laser scan speed and scan spacing on surface morphology, microstructure and structure evolution in direct laser sintering of Cu‐based metal powder.

Scanning electron microscope, differential thermal analyser (DTA) and X‐ray diffractometer were used to examine the microstructure of the sintered parts.

It was found that the decrease of the scan speed and scan spacing could lead to densification due to solute‐reprecipitation mechanism. The formation of oxide Cu₂O is sensitive to the scan spacing due to the lack of Cu₃P protection under the re‐heating condition if using small scan spacing. Furthermore, the result shows that there exist two mechanisms in determining the phosphor distribution. During the laser sintering, concentration diffusion acts as the main mechanism at a fast scan speed and a large scan spacing while solute‐reprecipitation acts as the main mechanism at a low scan speed and small scan spacing.

This paper discloses the influence of process parameters on microstructure evolution and the mechanism of densification in direct laser sintering Cu‐based metal powder. It offers practical help to the researchers who are interested in direct laser sintering metal powder.

This paper aims to propose methods to evaluate the characteristic length of the melt pool for accurate fabrication and to identify the optimal process parameters in the selective laser melting process.

Specimens with the types of the scans by controlling the degree of the overlap with hatch spacing are fabricated. The scan modes are classified by statistically analyzing the results of hardness tests. According to the classification of the scans, the evaluation methods are proposed based on the observation of the shape of the solidified melt pool.

The control of the hatch spacing can reproduce all modes of the scan conditions, and hardness can be used to classify the scan modes.

The proposed evaluation methods are based on the analysis of the experimental observation so that they can be easily used for the real evaluation.

Research on disciplinary literacy in English has struggled with how to represent large-scale disciplinary communities and consider issues of justice and power. The purpose of this study is to offer insights into the disciplinary practice of a community of literary scholars.

Using statistical topic modeling augmented with complementary qualitative analysis and interpretive rhetorical analysis, the authors describe patterns in a corpus of 4,039 articles published in the year 2018 and drawn from 215 peer-reviewed literary journals, a corpus comprising 15.5 million words.

Analysis suggests that contemporary literary scholars collectively build knowledge that considers diverse matters of form, including literary and linguistic forms, literary works and other representational forms; criticality, including critical theories and critical concepts; and humanity, including humanistic themes, human institutions and people/places.

This manuscript offers detail about the nature of contemporary literary scholarship as evident through linguistic patterns in and across published works.

Describes the effects of the major process variables (Q‐switch pulse frequency, laser power, scan speed, scan spacing and scan length) on the production of single layer coupons. Results are compiled as a list of qualitative effects on the samples, such as degree of melting, shock compression effects, thermal stress cracking, etc. The results show that at certain pulse frequencies, evaporation recoil forces overcome the surface tension forces acting on the melt, improving cohesion compared to continuous wave (CW) lasing regime. The advantages lie in greater scan spacing and scan speeds enabling faster processing times for metallic objects built in this manner. The results also show the effect of power, scan speed, scan spacing and scan length on the morphology of the samples.

The purpose of this research study was to examine school leaders’ critical perspectives about the nature of their partnerships with K-12 schools and two Educator Preparation Programs (EPP).

Data were collected through interviews with K-12 school leaders to obtain partners’ critical perspectives about school–EPP partnerships. The interviews were coded thematically and oriented around the central concept of working to represent the interplay of the participants and their collaborators’ perceptions of the nature and dimensions of school–EPP partnerships.

The analysis resulted in the construction of a mosaic of school leaders’ collective lived experiences using a statewide conceptual framework as a guide. Four themes emerged from our interviews with school partners: (a) the need for dynamic, responsive and synergistic partnerships; (b) the need to monitor and maintain the underlying structure and integrity of the partnership; (c) the culture of interns as colleagues or as visitors; and (d) the need to innovate.

Four themes emerged from our interviews with school partners: (1) the need for dynamic, responsive and synergistic partnerships; (2) the need to monitor and maintain the underlying structure and integrity of partnerships; (3) the culture of interns as colleagues or interns as visitors; and (4) the need to innovate.