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Recent field observations suggest that the air‐sea momentum flux (or the drag coefficient) is significantly reduced when the dominant wind‐forced surface waves are misaligned from local wind. Such conditions may occur under rapidly changing strong winds (such as under tropical cyclones) or in coastal shallow waters where waves are refracted by bottom topography. A recent Large Eddy Simulation (LES) study also shows that the drag coefficient is reduced by a misaligned strongly forced wave train (with a small wave age of 1.37). In order to investigate more realistic field conditions, this study employs LES to examine the effect of a misaligned (up to 90°) surface wave train over a wide range of wave age up to 10.95. For all wave ages examined, the drag coefficient is reduced compared to the flat surface condition when the misalignment angle exceeds around 22.5°–45°. The drag reduction may occur even if the form drag of the wave train is positive. Plain Language Summary: This study uses computer simulations to investigate turbulent wind blowing over ocean surface waves that are misaligned (propagate in different directions) from the wind. The study focuses on frictional wind forcing (wind stress) imparted on the ocean surface, because the wind stress is an important boundary condition for ocean, atmospheric, and surface wave models. Surface waves can be misaligned from wind when the wind field rapidly changes such as during tropical storms or in shallow water where wave directions are modified by varying water depth. When waves propagate slower than wind in the wind direction, the waves increase the wind stress compared to flat surface (no wave) conditions. However, this study finds that the wind stress is reduced, that is, the ocean surface becomes smoother, when the misalignment angle between wind and waves exceeds about 22.5°–45°. Key Points: Large eddy simulations are preformed to study wind over misaligned surface wavesDrag coefficient is reduced due to misaligned surface waves for all wave ages under wind‐driven wave conditionsDrag reduction can occur even when wave form drag is positive [ABSTRACT FROM AUTHOR]

As part of a research and professional development project that focused on the opportunities and constraints provided by different kinds of mathematical tasks, a group of 67 primary and 40 secondary practising teachers of mathematics were asked to complete a survey focusing on their use of tasks. In this article, we discuss responses to one particular item which sought teachers' ideas on taking a fraction comparison task (which is larger: 2/3 or 201/301?) and converting it into a mathematics lesson in the middle years of schooling. Drawing upon a number of components of "mathematical knowledge for teaching" as a framework, we attempt to examine those aspects of mathematical knowledge which are involved in making such a conversion. Our recommendation following this analysis is that greater emphasis is necessary in professional development settings on taking a potentially useful task and converting it into a worthwhile mathematics learning experience for students. Knowing the relevant mathematics also seems necessary even if not sufficient to make this conversion. (Contains 4 tables and 1 note.)

Middle school students have been pervasively described in the research literature as exhibiting disaffection, disengagement, and a lack of interest in mathematics classrooms. This study investigated this notion empirically using students' own voice on their wishes for mathematics learning to see if they characterise themselves in this way in their self-reports. Over 3500 Australian middle school students responded to a free-format prompt and reported diverse but overwhelmingly positive aspirations related to intrinsic motivational features inherent in their disposition and to extrinsic factors in their environment, such as the learning context and activities provided. Evidence of all four goal orientations was found in the students' responses but most noticeably for the productive mastery-approach orientation. When these students described what they wish for in their mathematics classrooms, they mentioned challenging work, interesting work, and opportunities to collaborate.

Productive struggle leads to productive classrooms where students work on complex problems, are encouraged to take risks, can struggle and fail yet still feel good about working on hard problems (Boaler, 2016). Teachers can foster a classroom culture that values and promotes productive struggle by providing students with challenging tasks. These tasks are designed in such a way that they are accessible to all students and the expectation is that everyone will persist when solving challenging mathematical tasks. This article looks at examples of challenging mathematical tasks designed to enable students of all abilities to experience productive struggle, and examines the lesson structure and teacher's role when implementing a challenging task, along with students' responses to being challenged through the tasks. It adds to existing research on challenging tasks, including in previous editions of "Australian Primary Mathematics Classroom" (APMC) (e.g., Cheeseman, Clarke, Roche, & Walker, 2016; Roche & Clarke, 2014; Russo, 2016) through challenging tasks being used to evoke productive struggle, and illustrative examples of what productive struggle 'looks like.'

Schematic models have been used extensively in educational research to represent relationships between variables diagrammatically, including the interrelationships between factors associated with teachers' beliefs and practices. A review of such models informed the development of a new model that was used to plan an investigation into primary school teachers' problem-solving beliefs and practices. On the basis of the findings from the research, the model was revised to include the important variable of prior mathematics learning, as well as a repositioning of the influence of teaching experiences in classrooms. (Contains 9 figures and 5 tables.)

Upper-ocean turbulence results from a complex set of interactions between submesoscale turbulence and local boundary layer processes. The interaction between larger-scale currents and turbulent fluctuations is two-way: large-scale shearing motions generate turbulence, and the resulting coherent turbulent fluxes of momentum and buoyancy feed back onto the larger flow. Here we examine the evolution and role of turbulence in the intensification, instability, arrest, and decay (i.e., the life cycle) of a dense filament undergoing frontogenesis in the upper-ocean boundary layer, i.e., cold filament frontogenesis (CFF). This phenomenon is examined in large-eddy simulations (LES) with resolved turbulent motions in large horizontal domains using 109 grid points. The boundary layer turbulence is generated by surface buoyancy loss (cooling flux) and is allowed to freely interact with an initially imposed cold filament, and the evolution is followed through the frontal life cycle. Two control parameters are explored: the initial frontal strength M2 = ∂xb and the surface flux Q * . The former is more consequent: initially weaker fronts sharpen more slowly and become arrested at a later time with a larger width. This reflects a competition between the frontogenetic rate induced by the secondary circulation associated with vertical momentum mixing by the turbulence and the instability rate for the along-filament shear flow. The frontal turbulence is energized by the shear production of the latter, is nonlocally transported away from the primary production zone at the filament centerline, and cascades to dissipation in a broad region surrounding the filament. The turbulent momentum fluxes arresting the frontogenesis are supported across a wide range of horizontal scales. [ABSTRACT FROM AUTHOR]

This article from Carly Sawatzki and Peter Sullivan encourages schools and teachers to consider ways to embed financial literacy tasks in mathematics lessons more often, and includes an authentic task to try with your students.

There is widespread international interest in parental education as a means of promoting educational equality through improving educational outcomes for young children. The research in this area suggests an association between the home learning environment and children's educational outcomes and highlights the importance of parental education for supporting young children's learning through play. This article reviews the international literature around parental education initiatives (or "interventions") in early childhood and then considers playgroups as potential sites for parental education. The article identifies the universal features of playgroups that make these sites appealing for the implementation of parental education initiatives and discusses the complexities associated with the design of interventions aimed at meeting the diverse needs of parents attending playgroups. It concludes by providing a case for community playgroups as cultural contexts, to be considered sites for parental education through curriculum aimed at supporting parents to actively engage in their children's learning and development through play.

While the general planning advice offered to mathematics teachers seems to be to start with simple examples and build complexity progressively, the research reported in this article is a contribution to the body of literature that argues the reverse. That is, posing of appropriately complex tasks may actually prompt the use of more sophisticated strategies. Results are presented from a detailed study of young children working on tasks that prompt multiplicative thinking. It was found that the tasks involving more complex number triples prompted the use of more sophisticated multiplicative thinking.

Abstract Background Communication about prognosis and treatment choices is essential for informed decision making in advanced cancer. This article describes an investigation designed to facilitate communication and decision making among oncologists, patients with advanced cancer, and their caregivers. Methods/design The Values and Options in Cancer Care (VOICE) Study is a National Cancer Institute sponsored randomized controlled trial conducted in the Rochester/Buffalo, NY and Sacramento, CA regions. A total of 40 oncologists, approximately 400 patients with advanced cancer, and their family/friend caregivers (one per patient, when available) are expected to enroll in the study. Drawing upon ecological theory, the intervention uses a two-pronged approach: oncologists complete a multifaceted tailored educational intervention involving standardized patient instructors (SPIs), and patients and caregivers complete a coaching intervention to facilitate prioritizing and discussing questions and concerns. Follow-up data will be collected approximately quarterly for up to three years. Discussion The intervention is hypothesized to enhance patient-centered communication, quality of care, and patient outcomes. Analyses will examine the effects of the intervention on key elements of physician-patient-caregiver communication (primary outcomes), the physician-patient relationship, shared understanding of prognosis, patient well-being, and health service utilization (secondary outcomes). Trial registration Clinical Trials Identifier: NCT01485627

The Canopy Horizontal Array Turbulence Study (CHATS) experimental study was conducted at a Cilker Orchards's walnut blocks in Dixon, California, before and after leaves emerged, to help improve understanding, simulation capabilities, and modeling of coupled vegetation-atmosphere-land surface interactions. The campaign took place over 12 weeks in the spring of 2007 and was broken into three 4-week phases. Canopy-induced mechanical and thermodynamical vertical variation of turbulence transport characteristics and the linkages between canopy-scale motions and the larger scale planetary boundary layer (PBL) turbulence were measured. The observations focused on measurements characterizing stratification influences on the spatial structure of canopy-induced turbulence, the trace gas source/sink distribution associated with vegetation, and the overall impact of canopy-induced processes on trace gas transport.

The following is a report on an investigation into ways of supporting teachers in converting challenging mathematics tasks into classroom lessons and supporting students in engaging with those tasks. Groups of primary and secondary teachers, respectively, were provided with documentation of ten lessons built around challenging tasks. Teachers responded to survey items in both Likert and free format style after teaching the ten lessons. The responses of the teacher participants indicate that the lesson structure we proposed was helpful, and the elements of the lessons suggested to teachers were both necessary and sufficient for supporting students in engaging with the challenging tasks. Implications for teacher educators and curriculum developers are offered.

The content and purpose of written unit plans in mathematics is an under-researched area. In this article, we provide a brief overview of research on teachers' planning processes and the place of mental and written plans. We report on data from a questionnaire completed by 357 teachers from Victorian Catholic primary schools, where we focused on possible elements of written unit plans for primary mathematics, and the relative importance which teachers attributed to these elements. We then discuss 48 written unit plans which were provided to us by primary schools from which the 357 teachers were drawn. There was considerable variation in the length, intended teaching time, and level of specification of key ideas in these plans. We discuss this variation, and some discrepancies between the ratings of teachers of the importance of certain elements and their presence in the plans we examined. We also suggest potentially productive areas of future enquiry.

Challenges for researchers wishing to gain insights into student beliefs about mathematics and learning include the identification of prompts to which young children can respond easily and which have the potential to provide meaningful insights into their beliefs. This article reports on a selection of such prompts used within an exploratory study that investigated beliefs about mathematics, learning and helping factors for learning mathematics of eight children of 8 to 9 years of age. These prompts, described as "creative interviewing" procedures, are classified under the key categories of visual, verbal and text-based. The article provides brief details of the study as background but focuses on discussing the nature of the tasks, and, through the inclusion of a selection of responses, illustrates their potential value as research tools for gaining insights into young children's beliefs about mathematics and learning. It seems that teachers could use the prompts to gain alternate perspectives into children's beliefs which in turn might inform their instruction.

Advances in coastal modeling and computation provide the opportunity for examining non-hydrostatic and compressible fluid effects at very small scales, but the cost of these new capabilities and the accuracy of these models versus trusted non-hydrostatic codes has yet to be determined. Here the Coastal and Regional Ocean COmmunity model (CROCO) and the NCAR Large-Eddy Simulations (NCAR-LES) code base are compared with a focus on their simulation accuracy and computational efficiency. These models differ significantly in numerics and capabilities, so they are run on common classic problems of surface-forced, boundary-layer turbulence. In accuracy, we compare turbulence statistics, including the effect of the explicit sub-grid scale (SGS) parameterization, the effect of the second (dilatational) viscosity and the sensitivity to the speed-of-sound, which is used as part of the CROCO compressible turbulence formulation. To gauge how far CROCO is from the NCAR-LES, we first compare the NCAR-LES with two other LES codes (PALM and Oceanigans). To judge efficiency of CROCO, strong and weak scaling simulation sets vary different problem sizes and workload per processor, respectively. Additionally, the effects of 2D decomposition of CROCO and NCAR-LES and supercomputer settings are tested. In sum, the accuracy comparison between CROCO and the NCAR-LES is similar to the NCAR-LES versus other LES codes. However, the additional capabilities of CROCO (e.g., nesting and realism) and its compressible turbulence formulation come with roughly an order of magnitude of additional costs despite efforts to reduce them by adjusting the second viscosity and sound speed as far as accuracy allows. [ABSTRACT FROM AUTHOR]