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Kumeyaay Language Loss and Revitalization
Indigenous populations around the world face the culturally devastating prospect of language loss. In the United States, Native communities are at risk. This study examines the challenge of language loss for the Kumeyaay Nation, located in southwestern portion of the United States. It explores the language loss experienced by the Kumeyaay people, as well as the impact this loss has had on its people in San Diego, California, and Baja California, Mexico. This is a uniquely Indigenous study: the author is a Kumeyaay tribal member and fluent language speaker, and Kumeyaay elders provide insight for policy recommendations. Interviews with extant Kumeyaay speakers reveal their small number and the difficulties of language transmission for the individual, family, and community. Perceptions of Kumeyaay elders about language atrophy are mapped onto UNESCO factors of language loss and are placed in the context of language socialization literature. The practices of extermination, containment, and later, of assimilation are shown to have directly and indirectly threatened the Kumeyaay language. Interviews show that elders’ perceptions about the state of the language are accurate, and they support the UNESCO supposition that small numbers of speakers and a lack of intergenerational language transmission can produce language atrophy. Prospects for current revitalization of the language depend upon an inventory of Kumeyaay language assets and innovative language transmission programs tailored to Native Kumeyaay communities
Frequency and Severity of Neutropenia Associated with Food and Drug Administration Approved and Compounded Formulations of Lomustine in Dogs with Cancer.
BackgroundCompounded lomustine is used commonly in veterinary patients. However, the potential variability in these formulations is unknown and concern exists that compounded formulations of drugs may differ in potency from Food and Drug Administration (FDA)-approved products.Hypothesis/objectivesThe initial objective of this study was to evaluate the frequency and severity of neutropenia in dogs treated with compounded or FDA-approved formulations of lomustine. Subsequent analyses aimed to determine the potency of lomustine obtained from several compounding pharmacies.AnimalsThirty-seven dogs treated with FDA-approved or compounded lomustine.MethodsDogs that received compounded or FDA-approved lomustine and had pretreatment and nadir CBCs performed were eligible for inclusion. Variables assessed included lomustine dose, neutrophil counts, and severity of neutropenia. Lomustine 5 mg capsules from 5 compounding sources were tested for potency using high-pressure liquid chromatography (HPLC) with ultraviolet (UV) detection.ResultsTwenty-one dogs received FDA-approved lomustine and 16 dogs were treated with lomustine prescribed from a single compounding pharmacy. All dogs treated with FDA-approved lomustine were neutropenic after treatment; 15 dogs (71%) developed grade 3 or higher neutropenia. Four dogs (25%) given compounded lomustine became neutropenic, with 2 dogs (12.5%) developing grade 3 neutropenia. The potency of lomustine from 5 compounding pharmacies ranged from 50 to 115% of the labeled concentration, with 1 sample within ±10% of the labeled concentration.Conclusions and clinical importanceThese data support broader investigation into the potency and consistency of compounded chemotherapy drugs and highlight the potential need for greater oversight of these products
Forecasting machine performance check output using Holt-Winters approach
Background: Machine Performance Check (MPC) is an automated TrueBeam quality control (QC) tool used to verify beam output, isocenter, and uniformity. The aim of this study was to build an MPC output variation time series modeled on the Holt-Winters method over thirty days.
Methods: After AAPM TG-51 and baseline data were established for the Edge TrueBeam, daily MPC output data were gathered and analyzed through a Holt-Winters (additive and multiplicative) method. The model's performance was assessed via three standard error measures: the mean squared error (MSE), the mean absolute percentage error (MAPE), and the mean absolute deviation (MAE). The aim was achieved using a nonlinear multistart solver on the Excel platform.
Results: The results showed that MPC output variation forecasting is energy and model dependent. Both additive and multiplicative Holt-Winters methods were suitable for the analysis. The performance metrics MSE, MAPE, and MAD were found to be well within acceptable limits.
Conclusions: A Holt-Winters model was able to accurately forecast the MPC output variation
Statistical process control: machine performance check output variation
Background: The aim of this study was to illustrate and evaluate the use of different statistical process control (SPC) aspects to examine linear accelerator daily output variation through machine performance check (MPC) over a month.
Methods: MPC daily output data were obtained over a month after AAPM TG-51 were performed. Baseline data were set, and subsequent data were conducted through SPC. The Shewhart chart was used to determine the upper and lower control limits, whereas CUSUM for subtle changes.
Results: The upper and lower control limits obtained via SPC analysis of the MPC data were found to fall within AAPM Task Group 142 guidelines. MPC output variation data were within ±3% of their action limits values and were within 1% over thirty days of data. The process capability ratio and process acceptability ratio, Cp and Cpk values were ≥2 for all energies. Potential undetected deviations were captured by the CUSUM chart for photons and electrons beam energy.
Conclusions: Control charts were found to be useful in terms of detecting changes in MPC output
On positivity of Ehrhart polynomials
Ehrhart discovered that the function that counts the number of lattice points
in dilations of an integral polytope is a polynomial. We call the coefficients
of this polynomial Ehrhart coefficients, and say a polytope is Ehrhart positive
if all Ehrhart coefficients are positive (which is not true for all integral
polytopes). The main purpose of this article is to survey interesting families
of polytopes that are known to be Ehrhart positive and discuss the reasons from
which their Ehrhart positivity follows. We also include examples of polytopes
that have negative Ehrhart coefficients and polytopes that are conjectured to
be Ehrhart positive, as well as pose a few relevant questions.Comment: 40 pages, 7 figures. To appear in in Recent Trends in Algebraic
Combinatorics, a volume of the Association for Women in Mathematics Series,
Springer International Publishin
Target Assembly to Check Boresight Alignment of Active Sensors
A compact and portable target assembly (Fig. 1) has been developed to measure the boresite alignment of LRO's Lunar Orbiter Laser Altimeter (LOLA) instrument at the spacecraft level. The concept for this target assembly has evolved over many years with earlier versions used to test the Mars Observer Laser Altimeter (MOLA), the Geoscience Laser Altimeter System (GLAS), and the Mercury Laser Altimeter (MLA) space-based instruments
Towards Deconstruction of the Type D (2,0) Theory
We propose a four-dimensional supersymmetric theory that deconstructs, in a
particular limit, the six-dimensional theory of type . This 4d
theory is defined by a necklace quiver with alternating gauge nodes
and . We test this proposal by comparing the
6d half-BPS index to the Higgs branch Hilbert series of the 4d theory. In the
process, we overcome several technical difficulties, such as Hilbert series
calculations for non-complete intersections, and the choice of
versus gauge groups. Consistently, the result matches the Coulomb
branch formula for the mirror theory upon reduction to 3d
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