On eigenvectors of nilpotent Lie algebras of linear operators

We give a condition ensuring that the operators in a nilpotent Lie algebra of linear operators on a finite dimensional vector space have a common eigenvector.Comment: Four page

Kant And The Conservation Of Matter

This dissertation is an examination of Kant\u27s rather notorious claim that natural science, or physics, has a priori principles, understood as the claim that physics is constrained by rules warranted by the essential nature of thought. The overall direction of this study is towards examining Kant\u27s claim by close study of a particular principle of physics, the principle of the conservation of matter. If indeed this is a principle of physics, and Kant can successfully show that it is a priori, then it will be reasonable to conclude, in company with Kant, that physics has a priori principles.;Although Kant\u27s proof of the principle of the conservation of matter has been traditionally regraded as a reasonably straightforward consequence of his First Analogy of Experience, a careful reading of his proof reveals that this is not really the case. Rather, Kant\u27s proof of the conservation of matter is a consequence of (i) his schematisation of the category of substance in terms of permanence, and (ii) his identification of matter as substance, by appeal to what he thinks is the empirical criterion of substance, activity.;Careful examination of Kant\u27s argument in defence of the principle of the conservation of matter, however, reveals a number of deficiencies, and it is concluded that Kant cannot be said to have satisfactorily demonstrated the principle of the conservation of matter or to have convincingly illustrated his claim that physics has a priori principles by appeal to this instance

A Description of Accommodations, Modifications, and Forms of Assessments in Middle Schools That Made Adequate Yearly Progress in an Urban County During 2010

Students with disabilities (SWD) have frequently been one of the subgroups not to make adequate yearly progress (AYP) in middle schools. If one subgroup does not meet the required objectives for meeting Adequate Yearly Progress (AYP), the entire school does not meet AYP. The purpose of this study was to identify accommodations, modifications, and forms of assessments that inclusion teachers find useful in middle schools that made adequately yearly progress. The researcher conducted a quantitative study. This study was a descriptive study using survey data. A total of 78 inclusion teachers participated in the study. The data indicated that inclusion teachers used presentation, response, and time/scheduling accommodations weekly and they used setting accommodations either weekly or seldom. Secondly, the survey data indicated all inclusion co-teachers used all of the five modifications on a weekly basis. Thirdly, the survey data indicated that inclusion teachers used: true-false quizzes, multiple choice test, and short answer tests as the forms of assessment. Inclusion teachers rarely used benchmark assessments, projects, portfolios or online assessments. More practice and training should be provided to administrators and inclusion teachers who practice co teaching in the inclusion classroom setting. Administrators should provide ongoing training to inclusion teachers on when to appropriately use accommodations, modifications, and forms of assessments

X-Ray Emission from the Pre-Planetary Nebula Henize 3-1475

We report the first detection of X-ray emission in a pre-planetary nebula, Hen 3-1475. Pre-planetary nebulae are rare objects in the short transition stage between the Asymptotic Giant Branch and planetary nebula evolutionary phases, and Hen 3-1475, characterised by a remarkable S-shaped chain of optical knots, is one of the most noteworthy members of this class. Observations with the Advanced CCD Imaging Spectrometer (ACIS) onboard the Chandra X-Ray observatory show the presence of compact emission coincident with the brightest optical knot in this bipolar object, which is displaced from the central star by 2.7 arcsec along the polar axis. Model fits to the X-ray spectrum indicate an X-ray temperature and luminosity, respectively, of (4.3-5.7) 10^6 K and (4+/-1.4) 10^{31} (D/5 kpc)^2 erg s^{-1}, respectively. Our 3-sigma upper limit on the luminosity of compact X-ray emission from the central star in Hen 3-1475 is ~5 10^{31} (D/5 kpc)^2 erg s^{-1}. The detection of X-rays in Hen 3-1475 is consistent with models in which fast collimated post-AGB outflows are crucial to the shaping of planetary nebulae; we discuss such models in the context of our observations.Comment: 2 figure

HIV transmission networks among transgender women in Los Angeles County, CA, USA: a phylogenetic analysis of surveillance data.

BackgroundTransgender women are among the groups at highest risk for HIV infection, with a prevalence of 27·7% in the USA; and despite this known high risk, undiagnosed infection is common in this population. We set out to identify transgender women and their partners in a molecular transmission network to prioritise public health activities.MethodsSince 2006, HIV protease and reverse transcriptase gene (pol) sequences from drug resistance testing have been reported to the Los Angeles County Department of Public Health and linked to demographic data, gender, and HIV transmission risk factor data for each case in the enhanced HIV/AIDS Reporting System. We reconstructed a molecular transmission network by use of HIV-TRAnsmission Cluster Engine (with a pairwise genetic distance threshold of 0·015 substitutions per site) from the earliest pol sequences from 22 398 unique individuals, including 412 (2%) self-identified transgender women. We examined the possible predictors of clustering with multivariate logistic regression. We characterised the genetically linked partners of transgender women and calculated assortativity (the tendency for people to link to other people with the same attributes) for each transmission risk group.Findings8133 (36·3%) of 22 398 individuals clustered in the network across 1722 molecular transmission clusters. Transgender women who indicated a sexual risk factor clustered at the highest frequency in the network, with 147 (43%) of 345 being linked to at least one other person (adjusted odds ratio [aOR] 2·0, p=0·0002). Transgender women were assortative in the network (assortativity 0·06, p<0·001), indicating that they tended to link to other transgender women. Transgender women were more likely than expected to link to other transgender women (OR 4·65, p<0·001) and cisgender men who did not identify as men who have sex with men (MSM; OR 1·53, p<0·001). Transgender women were less likely than expected to link to MSM (OR 0·75, p<0·001), despite the high prevalence of HIV among MSM. Transgender women were distributed across 126 clusters, and cisgender individuals linked to one transgender woman were 9·2 times more likely to link to a second transgender woman than other individuals in the surveillance database. Reconstruction of the transmission network is limited by sample availability, but sequences were available for more than 40% of diagnoses.InterpretationClustering of transgender women and the observed tendency for linkage with cisgender men who did not identify as MSM, shows the potential to use molecular epidemiology both to identify clusters that are likely to include undiagnosed transgender women with HIV and to improve the targeting of public health prevention and treatment services to transgender women.FundingCalifornia HIV and AIDS Research Program and National Institutes of Health-National Institute of Allergy and Infectious Diseases

Should the Insanity Defense be Abolished - An Introduction to the Debate

As the plans for the debate began to unfold I was concerned about the possibility that the subject matter might already be jaded, or in any event no longer would be a hot topic for our potential audience. Being quite familiar with the writings of our Advocates and therefore particularly susceptible to the reader-listener rehash syndrome, I was nonetheless hopeful that what had the potential for being old-hat would instead be new and interesting to those members of the audience not professionally committed to intimate familiarity with the subject matter. While I had expected that these issues, aired in the setting of a debate, would be more exciting and immediate than even the extraordinary written scholarship of both erudite visitors, I hadn\u27t expected the remarkable level of intensity, originality and profundity to which all of us were treated

Should the Insanity Defense be Abolished - An Introduction to the Debate

As the plans for the debate began to unfold I was concerned about the possibility that the subject matter might already be jaded, or in any event no longer would be a hot topic for our potential audience. Being quite familiar with the writings of our Advocates and therefore particularly susceptible to the reader-listener rehash syndrome, I was nonetheless hopeful that what had the potential for being old-hat would instead be new and interesting to those members of the audience not professionally committed to intimate familiarity with the subject matter. While I had expected that these issues, aired in the setting of a debate, would be more exciting and immediate than even the extraordinary written scholarship of both erudite visitors, I hadn\u27t expected the remarkable level of intensity, originality and profundity to which all of us were treated

An unusual two-step control of CPEB destruction by Pin1

Cytoplasmic polyadenylation is a conserved mechanism that controls mRNA translation and stability. A key protein that promotes polyadenylation-induced translation of mRNAs in maturing Xenopus oocytes is the cytoplasmic polyadenylation element binding protein (CPEB). During this meiotic transition, CPEB is subjected to phosphorylation-dependent ubiquitination and partial destruction, which is necessary for successive waves of polyadenylation of distinct mRNAs. Here we identify the peptidyl-prolyl cis-trans isomerase Pin1 as an important factor mediating CPEB destruction. Pin1 interacts with CPEB in an unusual manner in which it occurs prior to CPEB phosphorylation and prior to Pin1 activation by serine 71 dephosphorylation. Upon induction of maturation, CPEB becomes phosphorylated, which occurs simultaneously with Pin1 dephosphorylation. At this time, the CPEB-Pin1 interaction requires cdk1-catalyzed CPEB phosphorylation on S/T-P motifs. Subsequent CPEB ubiquitination and destruction are mediated by a conformational change induced by Pin1 isomerization of CPEB. Similar to M phase progression in maturing Xenopus oocytes, the destruction of CPEB during the mammalian cell cycle requires Pin1 as well. These data identify Pin1 as a new and essential factor regulating CPEB degradation