Curious sex ratios and cytoplasmic genes

Evolutionary theory predicts that most populations should consist of roughly as many males as females. Recently, a variety of populations have been described which show very different proportions of the two sexes, especially in invertebrate species that contain individuals whose offspring are almost all female. Some of these instances can now be explained by the diverse actions of various ‘selfish’ elements residing in the cytoplasm of the individuals, which are transmitted exclusively through the female line. These instances of curious sex ratios exemplify an important principle: the fitness of genes, rather than of individuals, is the primary currency of evolution.     

Predictors of College Attendance Patterns of Rural Youth

This study investigated patterns of college attendance using data from a nationwide and contemporary sample of 2112 rural youth. We found that more than half of rural youth attended two-year institutions at some point during their college career and about a fourth initially enrolled in a two-year college before enrolling in a four-year college. Results also revealed that parental education, college preparatory track and preparation experiences, and teacher expectations predicted students’ college attendance patterns. Our findings point to the importance of two-year colleges and highlight the influence of family characteristics and students’ schooling experiences in the postsecondary trajectories of rural youth.     

Job Crafting and Identity in Low-Grade Work: How Hospital Porters Redefine the Value of their Work and Expertise

Over 25 years ago, Brown and Duguid (Organisation Science, 2(1), 40–57, 1991) highlighted the differences between the way organisations formally describe and delineate jobs and the actual practices of their employees. This paper combines ideas from their seminal contribution with theories of ‘job crafting’ and identity to examine the agentic behaviour of employees in low-grade, ‘dirty work’ as they utilise their expertise and practices to (re)frame their occupational identities and challenge their prescribed job boundaries. The evidence for the paper comes from a qualitative study of hospital porters in the UK’s National Health Service. It argues that this combined theoretical approach provides a potential research and employment framework to challenge the abstracted and stereotypical conceptions of the expertise related to low-grade jobs.     

Raising the bar on studying cultural evolution

Sasaki and Biro (2017, Nature Communications, 8, 15049) show that pairs of pigeons can increase the efficiency of their homing routes over several ‘generations’ in which pair members are gradually replaced by naïve birds. Their findings show that socially transmitted cumulative alterations of behavior are not unique to humans and suggest a way to examine potential mechanisms of cultural evolution.     

An Investigation of How Culture Shapes Curriculum in Early Care and Education Programs on a Native American Indian Reservation

This article investigates how culture shapes instruction in three early care and education programs on the Flathead Indian Reservation. Interviews with eight early childhood teachers as well as classroom observations were conducted. The investigation is framed by the following research question: How does the culture of the family and community shape curriculum? Data analysis suggested that ongoing communication with parents and community about teaching within a culturally relevant context, building a sense of belongingness and community through ritual, and respecting children, families, and community were essential to defining the Native American Indian culture within these early learning programs.     

Effects of Second-Order Difference-Frequency Wave Forces on Floating Wind Turbine Under Survival Condition

In this paper, the effects of second-order difference-frequency wave forces on the global motion of an offshore wind turbine system with a large displacement under the survival condition are studied. In this case, the hydrodynamic force is the main force because the blades are feathered to reduce the lifting force. The first-order hydrodynamic forces are calculated by WADAM, while the second-order wave forces are calculated by a customized MATLAB module. Then the hydrodynamic coefficients are transferred to the wind turbine analytical code FAST. Through the comparisons of dynamic responses between the first- and second-order numerical models, it is found that the second-order wave forces significantly influence the motion of floating wind turbine under the survival condition. Moreover, neglecting the second-order force significantly underestimates the tension forces in the mooring lines.     

Pattern design on 3D triangular garment surfaces

This paper focuses on a pattern design method for a 3D triangular garment surface. Firstly, some definitions of 3D style lines are proposed for designing the boundaries of patterns as drawing straight lines or splines on the triangular surface. Additionally some commonly used style lines are automatically generated to enhance design efficiency. Secondly, after style lines are preprocessed, a searching method is presented for quickly obtaining the boundaries and patches of a pattern on the 3D trian- gular surface. Finally a new pattern design reuse method is introduced by encoding/decoding the style line information. After style lines are encoded, the pattern design information can be saved in a pattern template and when decoding this template on a new garment surface, it automates the pattern generation for made-to-measure apparel products.     

WVD的快速计算

The paper proposes a new method for computation of the Wigner-Ville distribution (WVD) taking account of the conjugate symmetry of the WVD kernel function and the periodicity and symmetry of the trigonometric function. The method transfers the computation of WVD into real field from complex field to remove the redundancies in the fast Fourier transform(FFT) computation. The realization of fast cosine operation and fast sine operation considerably reduces the computation cost. Theoretical analysis shows that     

That’s Not Something We Have to Discuss: Interrupting Silences About Multiracial Students in Teacher Work

The author asserts that the field of teacher education must begin a critical conversation to better prepare and support teachers in attending to the complexities of racialized identities, experiences, and perspectives of multiracial students in K12 schools. The author offers a review of literature relevant to multiracial students, and draws from the emerging theoretical framework of Multicrit (Harris in Int J Qual Stud Educ 29(6):795–813, 2016) to present monoracism, ahistoricism, colorism and intersectionality to analyze excerpts from three respective research studies. Each excerpt demonstrates an imperative to build a critical understanding of multiracial students within teacher work. The author concludes with implications for future research and practice.