Multilingualism in its Social Context in Aboriginal North America

Proceedings of the 4th Annual Meeting of the Berkeley Linguistics Society (1978), pp. 610-61

The effect of Ocuvite supplementation on the density of macular lutein and zeaxanthin

A major disease of the retina is age related macular degeneration, or ARMD. In this disease, the photoreceptor cells die and blindness results. Lutein and zeaxanthin, two carotenoids highly concentrated in the macular area, are thought to help protect against ARMD. Supplementation has been shown to raise macular pigment levels of lutein. It is proposed that Ocuvite (Bausch & Lomb) supplementation, which is a preparation of lutein plus other antioxidant molecules, will increase the macular pigment density of lutein and zeaxanthin. This study had forty-eight optometry students, twenty-four male and twenty-four female, who were divided into two groups. Group one, the control group, received no intervention. Group two, the experimental group, received one tablet of lutein daily for six months. Heterochromic flicker photometry, a psychophysical technique, was used to measure the macular pigment density level over a seven-month period. The macular pigment density level was assessed at baseline before any intervention, and then approximately every month for six months. Lutein did not significantly increase macular pigment density levels over a six-month period in the experimental group versus the control group

An unknown story: Majorana and the Pauli-Weisskopf scalar electrodynamics

An account is given of an interesting but unknown theory by Majorana regarding scalar quantum electrodynamics, elaborated several years before the known Pauli-Weisskopf theory. Theoretical calculations and their interpretation are given in detail, together with a general historical discussion of the main steps towards the building of a quantum field theory for electrodynamics. A possible peculiar application to nuclear constitution, as conceived around 1930, considered by Majorana is as well discussed.Comment: Latex, amsart, 20 pages, 2 figures; to be published in Annalen der Physi

Building A Culture of Scholarship with New Clinical Teachers By Writing About Social Justice Lawyering

This Article is a collection of essays about teaching social justice lawyering, as seen through the eyes of eight practitioners-in-residence in the clinical program at American University’s Washington College of Law (“WCL”). They include: Michelle Assad, Maria Dooner, Mariam Hinds, Jessica Millward, Citlalli Ochoa, Charles Ross, Anne Schaufele, and Caroline Wick. They teach in seven clinics, including the Civil Advocacy Clinic, the Criminal Justice Clinic, the Community Economic and Equity Development Clinic, the Disability Rights Law Clinic, the Immigrant Justice Clinic, the International Human Rights Law Clinic, and the Janet R. Spragens Federal Income Tax Clinic. We use the terms practitioner-in residence and practitioner interchangeably throughout this Article. These practitioners have full-time faculty status and represent a range of experience in our clinical program—from those who are in their first year of teaching in the program to those who have been teaching for several years and are near the end of their fellowships. Professors Assad, Millward, Schaufele, and Wick have now moved on to permanent teaching positions at other law schools, and Professor Dooner has returned to practice. They are all experienced lawyers who have brought their lawyering experiences in a variety of practice areas—criminal defense, criminal legal system reform, civil legal services, community and economic development, immigration, international human rights, employment, public benefits, health, tax law and policy, and special education—to their clinical teaching. They are diverse across a range of identities including race and ethnicity

Restoration of rotational invariance of bound states on the light front

We study bound states in a model with scalar nucleons interacting via an exchanged scalar meson using the Hamiltonian formalism on the light front. In this approach manifest rotational invariance is broken when the Fock space is truncated. By considering an effective Hamiltonian that takes into account two meson exchanges, we find that this breaking of rotational invariance is decreased from that which occurs when only one meson exchange is included. The best improvement occurs when the states are weakly bound.Comment: 20 pages, 6 figures, uses feynMF; changed typos, clarified use of angular momentu

Rapid detection of 2-hydroxyglutarate in frozen sections of IDH mutant tumors by MALDI-TOF mass spectrometry

All isocitrate dehydrogenase (IDH) mutant solid neoplasms exhibit highly elevated levels of D-2-hydroxyglutarate (D-2HG). Detection of 2HG in tumor tissues currently is performed by gas or liquid chromatography-mass spectrometry (GC- or LC-MS) or biochemical detection. While these methods are highly accurate, a considerable amount of time for tissue preparation and a relatively high amount of tissue is required for testing. We here present a rapid approach to detect 2HG in brain tumor tissue based on matrix-assisted laser desorption ionization - time of flight mass spectrometry (MALDI-TOF). We analyzed 26 brain tumor samples with known IDH1 or IDH2 mutation and compared readouts to those from 28 brain tumor samples of wildtype IDH status. IDH mutant samples exhibited a clear positive signal for 2HG which was not observed in any of the IDH wildtype tumors. Our analytical pipeline allowed for 2HG detection in less than 5 min. Data were validated by determining 2HG levels in all tissues with a biochemical assay. In conclusion, we developed a protocol for rapid detection of 2HG levels and illustrate the possibility to use MALDI-TOF for the detection of metabolites on frozen tissue sections in a diagnostic setting

An algebraic SU(1,1) solution for the relativistic hydrogen atom

The bound eigenfunctions and spectrum of a Dirac hydrogen atom are found taking advantage of the $SU(1, 1)$ Lie algebra in which the radial part of the problem can be expressed. For defining the algebra we need to add to the description an additional angular variable playing essentially the role of a phase. The operators spanning the algebra are used for defining ladder operators for the radial eigenfunctions of the relativistic hydrogen atom and for evaluating its energy spectrum. The status of the Johnson-Lippman operator in this algebra is also investigated.Comment: to appear in Physics Letters A (2005). We corrected a misprint in page 7, in the paragraph baggining with "With the value of ..." the ground state should be |\lambda, \lambda>, not |\lambda, \lambda+1

Angular Conditions,Relations between Breit and Light-Front Frames, and Subleading Power Corrections

We analyze the current matrix elements in the general collinear (Breit) frames and find the relation between the ordinary (or canonical) helicity amplitudes and the light-front helicity amplitudes. Using the conservation of angular momentum, we derive a general angular condition which should be satisfied by the light-front helicity amplitudes for any spin system. In addition, we obtain the light-front parity and time-reversal relations for the light-front helicity amplitudes. Applying these relations to the spin-1 form factor analysis, we note that the general angular condition relating the five helicity amplitudes is reduced to the usual angular condition relating the four helicity amplitudes due to the light-front time-reversal condition. We make some comments on the consequences of the angular condition for the analysis of the high-$Q^2$ deuteron electromagnetic form factors, and we further apply the general angular condition to the electromagnetic transition between spin-1/2 and spin-3/2 systems and find a relation useful for the analysis of the N-$\Delta$ transition form factors. We also discuss the scaling law and the subleading power corrections in the Breit and light-front frames.Comment: 24 pages,2 figure

Interacting meaningfully with machine learning systems: Three experiments

Although machine learning is becoming commonly used in today's software, there has been little research into how end users might interact with machine learning systems, beyond communicating simple “right/wrong” judgments. If the users themselves could work hand-in-hand with machine learning systems, the users’ understanding and trust of the system could improve and the accuracy of learning systems could be improved as well. We conducted three experiments to understand the potential for rich interactions between users and machine learning systems. The first experiment was a think-aloud study that investigated users’ willingness to interact with machine learning reasoning, and what kinds of feedback users might give to machine learning systems. We then investigated the viability of introducing such feedback into machine learning systems, specifically, how to incorporate some of these types of user feedback into machine learning systems, and what their impact was on the accuracy of the system. Taken together, the results of our experiments show that supporting rich interactions between users and machine learning systems is feasible for both user and machine. This shows the potential of rich human–computer collaboration via on-the-spot interactions as a promising direction for machine learning systems and users to collaboratively share intelligence

HASLR: Fast Hybrid Assembly of Long Reads

Third-generation sequencing technologies from companies such as Oxford Nanopore and Pacific Biosciences have paved the way for building more contiguous and potentially gap-free assemblies. The larger effective length of their reads has provided a means to overcome the challenges of short to mid-range repeats. Currently, accurate long read assemblers are computationally expensive, whereas faster methods are not as accurate. Moreover, despite recent advances in third-generation sequencing, researchers still tend to generate accurate short reads formany of the analysis tasks. Here,we present HASLR, a hybrid assembler that uses error-prone long reads together with high-quality short reads to efficiently generate accurate genome assemblies. Our experiments show that HASLR is not only the fastest assembler but also the one with the lowest number of misassemblies on most of the samples, while being on par with other assemblers in terms of contiguity and accuracy