Behaviour and effects of fluorine in annealed n+ polycrystalline silicon layers on silicon wafers

A comprehensive study is made of the behaviour and effects of fluorine in n+ polysilicon layers. Sheet resistance, TEM and SIMS are used to obtain quantitative data for the breakup of the interfacial oxide, the epitaxial regrowth of the polysilicon and the fluorine and arsenic distributions. The fluorine significantly increases both the initial oxide breakup and the initial polysilicon regrowth. It also produces inclusions in the layer which can affect the subsequent polysilicon regrowth and the arsenic distributions. Three regrowth stages and two regrowth mechanisms are distinguished and interpreted and a value of approximately 6x1011cm2s-1 is deduced for the effective diffusivity of fluorine in polysilicon at 950°C

Detecting squarefree numbers

We present an algorithm, based on the explicit formula for $L$-functions and conditional on GRH, for proving that a given integer is squarefree with little or no knowledge of its factorization. We analyze the algorithm both theoretically and practically, and use it to prove that several RSA challenge numbers are not squarefull.Comment: 31 pages, 3 figures, latest versio

The K- 12 Experiences of African American Criminal Offenders

This qualitative study explores some of the most persistent and significant racial gaps in our society today, focusing on the intersections of race, academic achievement, and criminal incarceration via an analysis of the K- 12 experiences of African American criminal offenders. The purpose of this research is to gain additional knowledge and insight about the racial disparities that persist in academic achievement and punitive methods of social control, hopefully contributing to the ongoing discussion of the ways in which to improve teacher practices and develop strategies for effectively engaging African American males in the classroom. There were three participants in this study, all adult African American males with varying levels of school success who have been criminally incarcerated. Each participant was interviewed about his school experiences. The interview data was analyzed and coded, and three primary themes emerged: school engagement, race, and violence. While incidents involving race and violence were present in each of the participants\u27 stories, the participants\u27 level of school engagement seemed to have the most profound effect on academic achievement and subsequent criminal involvement

Evaluation of fusarium wilt resistance in a flax germplasm

Non-Peer Reviewe

Characterization of flax germplasm for resistance to fusarium wilt

Non-Peer ReviewedFusarium wilt of flax (Linum usitatissimum L.) caused by Fusarium oxysporum f. sp. lini (Fol) is an economically important disease that can result in severe yield losses. Due to the pathogen’s ability to survive in soil for long periods, it is essential to identify fusarium wilt resistant flax varieties. The objectives of the study were to phenotype and compare a recombinant inbred line (RIL) population of flax in a controlled environment and in field wilt nurseries. Disease reaction of a subset (160) of RIL lines developed from cultivars ‘Aurore’ (moderately resistant) and ‘Oliver’ (susceptible) was assessed under controlled environment conditions to two Fol isolates. Disease severity was determined and the area under the disease progress curve (AUDPC) was calculated. The population varied in response from resistant to highly susceptible, indicating that resistant to wilt was probably polygenic. Twenty-eight days after inoculation, 14% and 5% of the RILs were severely wilted (scores of 8 and 9, with isolates 131 and 81, respectively). Plant height was negatively correlated with AUDPC (r2= -0.13155 for 131 and r2=-0.29841 for 81). Similarly, in the field in wilt nurseries, at Saskatoon and Morden, evaluation of the full set of 200 RILs, the disease reaction varied from resistant to susceptible, with 21% and 42% of RILs severely wilted (rated 8 and 9) at each site at the green boll stage. The results from the two locations were significantly different, although moderately correlated (r2=0.6127). The 160 RILs in controlled environment inoculated with isolates 131 and 81 showed a higher correlation for disease severity at 28 days after inoculation, with the wilt nursery in Saskatoon (r= 0.40028 and r2=0.38046) as compared to Morden (r2=0.33016 and r2=0.21140) at green boll stage. Differences in environmental and experimental conditions (such as seeding date) at the two locations, as well as different Fol strains in the soil combined with the subjectivity of the grading system may explain the differences between locations

Parvalbumin interneurons are differentially connected to principal cells in inhibitory feedback microcircuits along the dorso-ventral axis of the medial entorhinal cortex

The medial entorhinal cortex (mEC) shows a high degree of spatial tuning, predominantly grid cell activity, which is reliant on robust, dynamic inhibition provided by local interneurons (INs). In fact, feedback inhibitory microcircuits involving fast-spiking parvalbumin (PV) basket cells (BCs) are believed to contribute dominantly to the emergence of grid cell firing in principal cells (PrCs). However, the strength of PV BC-mediated inhibition onto PrCs is not uniform in this region, but high in the dorsal and weak in the ventral mEC. This is in good correlation with divergent grid field sizes, but the underlying morphologic and physiological mechanisms remain unknown. In this study, we examined PV BCs in layer (L)2/3 of the mEC characterizing their intrinsic physiology, morphology and synaptic connectivity in the juvenile rat. We show that while intrinsic physiology and morphology are broadly similar over the dorsoventral axis, PV BCs form more connections onto local PrCs in the dorsal mEC, independent of target cell type. In turn, the major PrC subtypes, pyramidal cell (PC) and stellate cell (SC), form connections onto PV BCs with lower, but equal probability. These data thus identify inhibitory connectivity as source of the gradient of inhibition, plausibly explaining divergent grid field formation along this dorsoventral axis of the mEC

Aseptic meningitis in a patient taking etanercept for rheumatoid arthritis: a case report

Background \ud We report a case of a 53 year old lady recently commenced on etanercept, an anti-TNF (tumour necrosis factor) therapy for rheumatoid arthritis presenting with \ud confusion, pyrexia and an erythematous rash. \ud \ud Case presentation \ud A lumbar puncture was highly suggestive of bacterial meningitis, but CSF cultures produced no growth, and polymerase chain reactions (PCR) for all previously reported bacterial, fungal and viral causes of meningitis were negative. \ud \ud Conclusions \ud This case report describes aseptic meningitis as a previously unreported complication of etanercept therapy, and serves as a reminder of the rare but potentially lifethreatening risk of serious infections in patients taking anti-TNF therapy for a variety of conditions