On the inverse image of pattern classes under bubble sort

Let B be the operation of re-ordering a sequence by one pass of bubble sort. We completely answer the question of when the inverse image of a principal pattern class under B is a pattern class.Comment: 11 page

Improved model of the triple system V746 Cas that has a bipolar magnetic field associated with the tertiary

V746 Cas is known to be a triple system composed of a close binary with an alternatively reported period of either 25.4d or 27.8d and a third component in a 62000d orbit. The object was also reported to exhibit multiperiodic light variations with periods from 0.83d to 2.50d, on the basis of which it was classified as a slowly pulsating B star. Interest in further investigation of this system was raised by the detection of a variable magnetic field. Analysing spectra from four instruments, earlier published radial velocities, and several sets of photometric observations, we arrived at the following conclusions: (1) The optical spectrum is dominated by the lines of the B-type primary (Teff1~16500(100) K), contributing 70% of the light in the optical region, and a slightly cooler B tertiary (Teff3~13620(150) K). The lines of the low-mass secondary are below our detection threshold; we estimate that it could be a normal A or F star. (2) We resolved the ambiguity in the value of the inner binary period and arrived at a linear ephemeris of T_super.conj.=HJD 2443838.78(81)+25.41569(42)xE. (3) The intensity of the magnetic field undergoes a~sinusoidal variation in phase with one of the known photometric periods, namely 2.503867(19)d, which we identify with the rotational period of the tertiary. (4) The second photometric 1.0649524(40)d period is identified with the rotational period of the B-type primary, but this interpretation is much less certain and needs further verification. (5) If our interpretation of photometric periods is confirmed, the classification of the object as a slowly pulsating B star should be revised. (6) Applying an N-body model to different types of available observational data, we constrain the orbital inclination of the inner orbit to ~60 deg to 85 deg even in the absence of eclipses, and estimate the probable properties of the triple system and its components.Comment: Accepted for publication in Astronomy and Astrophysic

A Review of Landscape Water Requirements Using a Multicomponent Landscape Coefficient

Water requirements of landscapes are highly variable due to the heterogeneous natures of landscapes, vegetation types, influence of buildings, and nutrient and water management. Objectives for water management of landscapes are for general appearance and health rather than for maximum biomass production. A multi-component method developed for the Irrigation Association (IA) and extended from the California WUCOLS procedure is demonstrated in which the landscape coefficient (KL, equivalent to a crop coefficient) is broken down into four components: vegetation type, vegetation density, microclimate, and managed stress. Each of these components can be estimated using readily made descriptions of a landscaped area and management objectives. One form of the KL equation is used to determine target KL that incorporates a target amount of soil water stress to support water conservation and to support water planning studies. A second form of the KL equation can be used to estimate the actual KL occurring under actual water management. The second form is used in studies of water balances and actual water conservation. The general decoupled equation is further expanded to optionally incorporate impacts of evaporation from exposed soil to assess impacts of irrigation frequency on total water consumption. The mathematics for the approach can be incorporated into software applications and smart irrigation controllers to produce improved water consumption estimates for landscape water requirements for use in irrigation scheduling, water requirement planning, and water depletion studies. The simplified procedure for estimating landscape water requirements in ASABE Standard S623 that is complementary to the IA procedure is discussed and compared. Both methods use a vegetation type and density system as the basis for efficiently estimating scientifically accurate landscape water requirements

The impact of COVID-19 on anxiety and wellbeing for families of individuals with Special Education Needs and Disabilities in the UK

COVID-19 has affected people across the world. However, it has been suggested that individuals with Special Education Needs and Disabilities (SEND) and their families might have been particularly impacted by the first national lockdown in the UK. In contrast to previous studies, the current study examined wellbeing and anxiety at different time points and included a control group matched for family situation. Parents of 402 individuals with SEND reported on their own anxiety and wellbeing as well as that of their son/daughter at three time points (before COVID-19, when COVID-19 pandemic started, and during the national lockdown). In addition, data from 186 typically developing (TD) siblings was obtained. Repeated measures ANOVAs and regression analyses showed that, although both individuals with SEND and their TD siblings showed increased anxiety across the three time points, levels of anxiety were not predicted by age, gender or health. Instead, levels of anxiety in the SEND group, but not the TD siblings, were predicted by awareness about COVID-19, diagnosis of an existing anxiety disorder as well as parental anxiety. In addition, whilst TD individuals were reported to increasingly worry about social related issues as well as family related issues, those with SEND were reported to worry about issues related to school closures. These findings show that COVID-19 impacts the wellbeing of those with SEND differently to that of their TD siblings and that school closures have a particular effect on this group. Further implications for policy impact and interventions are discussed

Random tree growth by vertex splitting

We study a model of growing planar tree graphs where in each time step we separate the tree into two components by splitting a vertex and then connect the two pieces by inserting a new link between the daughter vertices. This model generalises the preferential attachment model and Ford's $\alpha$-model for phylogenetic trees. We develop a mean field theory for the vertex degree distribution, prove that the mean field theory is exact in some special cases and check that it agrees with numerical simulations in general. We calculate various correlation functions and show that the intrinsic Hausdorff dimension can vary from one to infinity, depending on the parameters of the model.Comment: 47 page

Emerging technologies for sustainable irrigation: Selected papers from the 2015 ASABE and IA irrigation symposium

Citation: Lamm, F. R., Stone, K. C., Dukes, M. D., Howell, T. A., Sr., Robbins, J. W. D., Jr., & Mecham, B. Q. (2016). Emerging technologies for sustainable irrigation: Selected papers from the 2015 ASABE and IA irrigation symposium. Transactions of the Asabe, 59(1), 155-161. doi:10.13031/trans.59.11706This article is an introduction to the "Emerging Technologies in Sustainable Irrigation: A Tribute to the Career of Terry Howell, Sr." Special Collection in this issue of Transactions of the ASABE and the next issue of Applied Engineering in Agriculture, consisting of 16 articles selected from 62 papers and presentations at the joint irrigation symposium of ASABE and the Irrigation Association (IA), which was held in November 2015 in Long Beach, California. The joint cooperation on irrigation symposia between ASABE and IA can be traced back to 1970, and this time period roughly coincides with the career of Dr. Howell. The cooperative symposia have offered an important venue for discussion of emerging technologies that can lead to sustainable irrigation. This most recent symposium is another point on the continuum. The articles in this Special Collection address three major topic areas: evapotranspiration measurement and determination, irrigation systems and their associated technologies, and irrigation scheduling and water management. While these 16 articles are not inclusive of all the important advances in irrigation since 1970, they illustrate that continued progress occurs by combining a recognition of the current status with the postulation of new ideas to advance our understanding of irrigation engineering and science. The global food and water challenges will require continued progress from our portion of the scientific community. This article serves to introduce and provide a brief summary of the Special Collection. © 2016 American Society of Agricultural and Biological Engineers

Brief Report: A Cross-Sectional Study of Anxiety Levels and Concerns of Chinese Families of Children With Special Educational Needs and Disabilities Post-first-wave of COVID-19

The COVID-19 pandemic has a multifaceted impact on mental health due to ill health, restrictions and lockdowns, and loss of employment and institutional support. COVID-19 may disproportionally impact families with special educational needs and disabilities (SEND) due to the already higher prevalence of mental health conditions in children with SEND and their parents. Therefore, it is essential to determine the short-term impact of the pandemic on the mental health of families with SEND in order to identify their ongoing health support needs. The current study aims to examine the anxiety level and concerns of children with SEND and their parents living in China. The sample consisted of 271 parents of children with SEND aged between 6 and 17 years (M age = 8.37; SD age = 2.76). Parents completed an online survey between 10 April to 8 June 2020. Both child and parental anxiety levels and various concerns increased after the initial wave of COVID-19 when compared with retrospective pre-COVID-19 levels. Parental anxiety and concern levels were significantly higher for those living in rural areas compared to urban areas. In addition, parental and child anxiety and concern levels were significantly correlated with each other. Parental anxiety at the lowest level made a unique and significant statistical contribution to children's anxiety levels. The implications of the study findings are discussed