Genetic Variation in Resistance of Scotch Pine to Zimmerman Pine Moth

(excerpt) Scotch pine (Pinus sylvestris L.), a forest tree introduced from Eurasia, is commonly planted for Christmas tree and timber use in northeastern United States. In this country it has numerous insect enemies. Among the most important are European pine shoot moth, Rhyacionia buoliana (Schiffermiieller); pine root collar weevil, Hylobius radicis Buchanan;,European pine sawfly, Neodiprion sertifer (Geoffroy); and eastern white-pine shoot borer, Eucosma gloriola Heinrich. Previous studies (Wright et al., 1967; Wright and Wilson, 1972; Steiner, 1974) have revealed large genetic differences in resistance to some of these pests. Another destructive pest is the Zimmerman pine moth, Dioryctria zimmermani (Grote). In 1968 this insect, native to the United States, was found attacking trees in a Scotch pine provenance test in southwestern Michigan. The attack rate was heavy and by 1973 it was obvious that some rams or varieties were attacked more heavily than others. This is a report on those differences

The Brauer-Manin Obstruction and Sha[2].

We discuss the Brauer-Manin obstruction on del Pezzo surfaces of degree 4. We outline a detailed algorithm for computing the obstruction and provide associated programs in magma. This is illustrated with the computation of an example with an irreducible cubic factor in the singular locus of the defining pencil of quadrics (in contrast to previous examples, which had at worst quadratic irreducible factors). We exploit the relationship with the Tate-Shafarevich group to give new types of examples of Sha[2], for families of curves of genus 2 of the form y^2 = f(x), where f(x) is a quintic containing an irreducible cubic factor

New observations regarding deterministic, time reversible thermostats and Gauss's principle of least constraint

Deterministic thermostats are frequently employed in non-equilibrium molecular dynamics simulations in order to remove the heat produced irreversibly over the course of such simulations. The simplest thermostat is the Gaussian thermostat, which satisfies Gauss's principle of least constraint and fixes the peculiar kinetic energy. There are of course infinitely many ways to thermostat systems, e.g. by fixing $\sum\limits_i{|{p_i}|^{\mu + 1}}$. In the present paper we provide, for the first time, convincing arguments as to why the conventional Gaussian isokinetic thermostat ($\mu=1$) is unique in this class. We show that this thermostat minimizes the phase space compression and is the only thermostat for which the conjugate pairing rule (CPR) holds. Moreover it is shown that for finite sized systems in the absence of an applied dissipative field, all other thermostats ($\mu=1$) perform work on the system in the same manner as a dissipative field while simultaneously removing the dissipative heat so generated. All other thermostats ($\mu=1$) are thus auto-dissipative. Among all $\mu$-thermostats, only the $\mu=1$ Gaussian thermostat permits an equilibrium state.Comment: 27 pages including 10 figures; submitted for publication Journal of Chemical Physic

The professional socialisation of headteachers in England: Further findings from the National Headteacher Survey

This paper reports on a further investigation of data first accumulated through a national survey of headteachers conducted in 1999. The survey was conducted by means of a self-completion postal questionnaire with a stratified random sample of 10 per cent serving headteachers in England, totalling 2285 potential respondents in all. Completed returns were received from 1405 headteachers, an overall response rate of 62 per cent. Initial findings from the survey have subsequently been published as conference papers and journal articles (Male, 2000; Male and Hvizdak, 2000; Male and Male, 2001, Male 2001). The survey primarily sought to establish the respondents’ perceived state of readiness for the demands of the headteacher position in a number of job categories and competencies. A secondary aim was to allow respondents to attribute reasons to their state of readiness where they perceived it to be adequate or better. A third aim was to seek opinion from the respondents as to what provision and support would be beneficial to headteachers in their first two years in post. This further investigation has been commissioned by the National College for School Leadership and has been conducted by the original author, aided by two serving headteachers who have been appointed as research associates by the college during the period January to July of 2002

Causes and Solutions of Mathematics Phobia Among Secondary School Students

The study investigated the causes and solutions to mathematics phobia among secondary school students. The study was carried in Owerri North local Government of Imo State. The descriptive survey research design was adopted in carrying out the study. A sample of 110 mathematics teacher was selected for the study through random sampling technique. A researcher made 4-points likert type of questionnaire titled “Causes and Solutions of Mathematics Phobia(CSMP)”was used for data collection, it had reliability coefficient of 0.81 determined using the crounbach’s alpha formula. The generated data was analyzed using mean and standard deviation to answer research questions while the hypothesis was analyzed using chi-square(x2) and tested at 0.05 level of significance. The result of the study revealed among other factors, teachers method of teaching, teacher-students relationship, use of abusive words on students as causes of mathematics phobia among students. Based on the result it was recommended that, mathematics teachers should be retrained periodically in order to have ideas of innovative approaches of teaching mathematics to avoid phobia. Keywords: causes, solutions, mathematics phobia, innovative approaches

HUNTINGTON’S DISEASE: CURRENT ADVANCES AND FUTURE PROSPECTS

Huntington’s disease is a neurodegenerative disease which is caused by dominantly inherited cytosine-adenine-guanine trinucleotide repeat expansion in the huntingtin gene of chromosome 4. Present survey reveals 2.7 per 100000 people are affected by huntington’s disease worldwide. The symptoms present with these patients are progressive motor, cognitive and psychiatric disorders. The early symptoms are chorea and loss of balance. This review aims to observe the present data available concerning huntington’s disease, symptoms, age of onset, risk factors, benefits of early diagnosis and genetic attribution. There is no cure for the disease. The article searched, selected and reviewed were from google scholar, medscape, NIH MedlinePlus, PubMed database using MeSH terms huntington’s disease, recent therapeutic advancement from 2003 to July 2021 with no language restriction and additional studies were included from the reference lists of relevant articles. The present review provides clinical features, diagnosis, symptomatic management and ongoing research. Hence this review will have an impact to create awareness for the society and researchers to find future treatment for Huntington’s disease

How Do Individuals in a Radical Echo Chamber React to Opposing Views? Evidence from a Content Analysis of Stormfront

Calls to “break up” radical echo chambers by injecting them with alternative viewpoints are common. Yet, thus far there is little evidence about the impact of such counter-messaging. To what extent and how do individuals who inhabit a radical echo chamber engage with messages that challenge their core beliefs? Drawing on data from the radical right forum Stormfront we address this question with a large-scale content and longitudinal analysis of users’ posting behavior, which analyses more than 35,000 English language contributions to the forum spanning 2011 through 2013. Our findings show that engaging with oppositional views is actually a core practice among Stromfront users which invites active participation and encourages engagement. Indeed, many “echoes” in the echo chamber we studied were not core beliefs being restated, but the sound of opposing viewpoints being undermined and marginalized. These findings underscore the limited potential for counter-messages to undermine radical echo chambers

The RCB star V854 Cen is surrounded by a hot dusty shell

Aims : The hydrogen-deficient supergiants known as R Coronae Borealis (RCB) stars might be the result of a double-degenerate merger of two white dwarfs (WDs), or a final helium shell flash in a planetary nebula central star. In this context, any information on the geometry of their circumstellar environment and, in particular, the potential detection of elongated structures, is of great importance. Methods : We obtained near-IR observations of V854 Cen with the AMBER recombiner located at the Very Large Telescope Interferometer (VLTI) array with the compact array (B$\leq$35m) in 2013 and the long array (B$\leq$140m) in 2014. At each time, V854 Cen was at maximum light. The $H$- and $K$-band continua were investigated by means of spectrally dependant geometric models. These data were supplemented with mid-IR VISIR/VLT images. Results : A dusty slightly elongated over density is discovered both in the $H$- and $K$-band images. With the compact array, the central star is unresolved ($\Theta\leq2.5$\,mas), but a flattened dusty environment of $8 \times 11$ mas is discovered whose flux increases from about $\sim$20% in the $H$ band to reach about $\sim$50% at 2.3\micron, which indicates hot (T$\sim$1500\,K) dust in the close vicinity of the star. The major axis is oriented at a position angle (P.A.) of 126$\pm$29$\deg$. Adding the long-array configuration dataset provides tighter constraints on the star diameter ($\Theta\leq1.0$ mas), a slight increase of the overdensity to $12 \times 15$ mas and a consistent P.A. of 133$\pm$49$\deg$. The closure phases, sensitive to asymmetries, are null and compatible with a centro-symmetric, unperturbed environment excluding point sources at the level of 3% of the total flux in 2013 and 2014. The VISIR images exhibit a flattened aspect ratio at the 15-20% level at larger distances ($\sim$1\arcsec) with a position angle of 92$\pm$19$\deg$, marginally consistent with the interferometric observations. Conclusions : This is the first time that a moderately elongated structure has been observed around an RCB star. These observations confirm the numerous suggestions for a bipolar structure proposed for this star in the literature, which were mainly based on polarimetric and spectroscopic observations.Comment: Accepted by A\&A, new version after language editing, Astronomy and Astrophysics (2014

Perception of Time Since Smoking Cessation: Time in Memory Can Elapse Faster

Self-reports concerning smoking behaviors are subject to different types of response bias that may severely affect the data quality. This study examined the evidence and extent of backward telescoping bias in reports on time since completely quitting smoking among former smokers. The study goals were to determine whether the extent of bias differs, on average, across subpopulations with diverse sociodemographic characteristics, prior smoking habits and duration of smoking abstinence, and across the survey administration mode (phone, in-person, mixed). The sample included 1,611 subjects who responded to the 2002–2003 Tobacco Use Supplement to the Current Population Survey. Multiple regressions for subjects who quit smoking recently, some time ago, and a long time ago were fitted, where the variance was estimated via the Balanced Repeated Replications approach. The model-based estimates were used to compare the extent of response bias across diverse subpopulations of respondents. Analyses revealed a significantly smaller overall extent of response bias for respondents who were younger (p \u3c 0.01), female (p \u3c 0.01), Non-Hispanic White (p = 0.02), employed (p \u3c 0.01), who were regular (rather than occasional) smokers in the past (p \u3c 0.01), and who quit smoking recently or some time ago as opposed to a long time ago (p \u3c 0.01); a significant overall effect of survey mode was also detected (p \u3c 0.01). Male respondents who smoked occasionally in the past tended to provide the most disagreeing reports. The discrepancy in reports may be due to backward telescoping bias. Studies which use the national survey smoking cessation measures should be aware of not only possible forward telescoping (that has been addressed in the literature) but also backward telescoping. This will help correctly account for possible impaired perception of time elapsed since smoking cessation in former smokers