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Teaching linguistics gotta catch ’em all: Skills grading in undergraduate linguistics
Dissatisfied with traditional grading, we developed a grading system to directly assess whether students have mastered course material. We identified the set of skills students need to master in a course and provided multiple opportunities for students to demonstrate mastery of each skill. We describe in detail how we implemented the system for two undergraduate courses, Introductory Phonetics and Phonology I. Our goals were to decrease student stress, increase student learning and make students’ study efforts more effective, increase students’ metacognitive awareness, promote a growth mindset, encourage students to aim for mastery rather than partial credit, be fairer to students facing structural and institutional disadvantages, reduce our time spent on grading, and facilitate complying with new accreditation requirements. Our own reflections and student feedback indicate that many of these goals were met
Busy Beaver Scores and Alphabet Size
We investigate the Busy Beaver Game introduced by Rado (1962) generalized to
non-binary alphabets. Harland (2016) conjectured that activity (number of
steps) and productivity (number of non-blank symbols) of candidate machines
grow as the alphabet size increases. We prove this conjecture for any alphabet
size under the condition that the number of states is sufficiently large. For
the measure activity we show that increasing the alphabet size from two to
three allows an increase. By a classical construction it is even possible to
obtain a two-state machine increasing activity and productivity of any machine
if we allow an alphabet size depending on the number of states of the original
machine. We also show that an increase of the alphabet by a factor of three
admits an increase of activity
Birth weight and risk of ischemic heart disease: A Mendelian randomization study
published_or_final_versio
Examination of the Relationship between In-Store Environmental Factors and Fruit and Vegetable Purchasing among Hispanics.
Retail food environments have received attention for their influence on dietary behaviors and for their nutrition intervention potential. To improve diet-related behaviors, such as fruit and vegetable (FV) purchasing, it is important to examine its relationship with in-store environmental characteristics. This study used baseline data from the "El Valor de Nuestra Salud" study to examine how in-store environmental characteristics, such as product availability, placement and promotion, were associated with FV purchasing among Hispanic customers in San Diego County. Mixed linear regression models indicated that greater availability of fresh FVs was associated with a 0.02 increase and 3.69 fewer dollars on FVs compared to women, controlling for covariates (p = 0.02). These results can help inform interventions targeting in-store environmental characteristics to encourage FV purchasing among Hispanics
Hepatic fibrogenesis requires sympathetic neurotransmitters
Background and aims: Hepatic stellate cells (HSC) are activated by liver injury to become proliferative fibrogenic myofibroblasts. This process may be regulated by the sympathetic nervous system (SNS) but the mechanisms involved are unclear. Methods: We studied cultured HSC and intact mice with liver injury to test the hypothesis that HSC respond to and produce SNS neurotransmitters to promote fibrogenesis. Results: HSC expressed adrenoceptors, catecholamine biosynthetic enzymes, released norepinephrine (NE), and were growth inhibited by α- and β-adrenoceptor antagonists. HSC from dopamine β-hydroxylase deficient (Dbh(−/−)) mice, which cannot make NE, grew poorly in culture and were rescued by NE. Inhibitor studies demonstrated that this effect was mediated via G protein coupled adrenoceptors, mitogen activated kinases, and phosphatidylinositol 3-kinase. Injury related fibrogenic responses were inhibited in Dbh(−/−) mice, as evidenced by reduced hepatic accumulation of α-smooth muscle actin(+ve) HSC and decreased induction of transforming growth factor β1 (TGF-β1) and collagen. Treatment with isoprenaline rescued HSC activation. HSC were also reduced in leptin deficient ob/ob mice which have reduced NE levels and are resistant to hepatic fibrosis. Treating ob/ob mice with NE induced HSC proliferation, upregulated hepatic TGF-β1 and collagen, and increased liver fibrosis. Conclusions: HSC are hepatic neuroglia that produce and respond to SNS neurotransmitters to promote hepatic fibrosis
The relationship between the systemic inflammatory response, tumour proliferative activity, T-lymphocytic and macrophage infiltration, microvessel density and survival in patients with primary operable breast cancer
The significance of the inter-relationship between tumour and host local/systemic inflammatory responses in primary operable invasive breast cancer is limited. The inter-relationship between the systemic inflammatory response (pre-operative white cell count, C-reactive protein and albumin concentrations), standard clinicopathological factors, tumour T-lymphocytic (CD4+ and CD8+) and macrophage (CD68+) infiltration, proliferative (Ki-67) index and microvessel density (CD34+) was examined using immunohistochemistry and slide-counting techniques, and their prognostic values were examined in 168 patients with potentially curative resection of early-stage invasive breast cancer. Increased tumour grade and proliferative activity were associated with greater tumour T-lymphocyte (P<0.05) and macrophage (P<0.05) infiltration and microvessel density (P<0.01). The median follow-up of survivors was 72 months. During this period, 31 patients died; 18 died of their cancer. On univariate analysis, increased lymph-node involvement (P<0.01), negative hormonal receptor (P<0.10), lower albumin concentrations (P<0.01), increased tumour proliferation (P<0.05), increased tumour microvessel density (P<0.05), the extent of locoregional control (P<0.0001) and limited systemic treatment (Pless than or equal to0.01) were associated with cancer-specific survival. On multivariate analysis of these significant covariates, albumin (HR 4.77, 95% CI 1.35–16.85, P=0.015), locoregional treatment (HR 3.64, 95% CI 1.04–12.72, P=0.043) and systemic treatment (HR 2.29, 95% CI 1.23–4.27, P=0.009) were significant independent predictors of cancer-specific survival. Among tumour-based inflammatory factors, only tumour microvessel density (P<0.05) was independently associated with poorer cancer-specific survival. The host inflammatory responses are closely associated with poor tumour differentiation, proliferation and malignant disease progression in breast cancer
On the selection and design of proteins and peptide derivatives for the production of photoluminescent, red-emitting gold quantum clusters
Novel pathways of the synthesis of photoluminescent gold quantum clusters (AuQCs) using biomolecules as reactants provide biocompatible products for biological imaging techniques. In order to rationalize the rules for the preparation of red-emitting AuQCs in aqueous phase using proteins or peptides, the role of different organic structural units was investigated. Three systems were studied: proteins, peptides, and amino acid mixtures, respectively. We have found that cysteine and tyrosine are indispensable residues. The SH/S-S ratio in a single molecule is not a critical factor in the synthesis, but on the other hand, the stoichiometry of cysteine residues and the gold precursor is crucial. These observations indicate the importance of proper chemical behavior of all species in a wide size range extending from the atomic distances (in the AuI-S semi ring) to nanometer distances covering the larger sizes of proteins assuring the hierarchical structure of the whole self-assembled system
Input-to-state stability of infinite-dimensional control systems
We develop tools for investigation of input-to-state stability (ISS) of
infinite-dimensional control systems. We show that for certain classes of
admissible inputs the existence of an ISS-Lyapunov function implies the
input-to-state stability of a system. Then for the case of systems described by
abstract equations in Banach spaces we develop two methods of construction of
local and global ISS-Lyapunov functions. We prove a linearization principle
that allows a construction of a local ISS-Lyapunov function for a system which
linear approximation is ISS. In order to study interconnections of nonlinear
infinite-dimensional systems, we generalize the small-gain theorem to the case
of infinite-dimensional systems and provide a way to construct an ISS-Lyapunov
function for an entire interconnection, if ISS-Lyapunov functions for
subsystems are known and the small-gain condition is satisfied. We illustrate
the theory on examples of linear and semilinear reaction-diffusion equations.Comment: 33 page
New zebrafish models of neurodegeneration
In modern biomedicine, the increasing need to develop experimental models to further our understanding of disease conditions and delineate innovative treatments has found in the zebrafish (Danio rerio) an experimental model, and indeed a valuable asset, to close the gap between in vitro and in vivo assays. Translation of ideas at a faster pace is vital in the field of neurodegeneration, with the attempt to slow or prevent the dramatic impact on the society's welfare being an essential priority. Our research group has pioneered the use of zebrafish to contribute to the quest for faster and improved understanding and treatment of neurodegeneration in concert with, and inspired by, many others who have primed the study of the zebrafish to understand and search for a cure for disorders of the nervous system. Aware of the many advantages this vertebrate model holds, here, we present an update on the recent zebrafish models available to study neurodegeneration with the goal of stimulating further interest and increasing the number of diseases and applications for which they can be exploited. We shall do so by citing and commenting on recent breakthroughs made possible via zebrafish, highlighting their benefits for the testing of therapeutics and dissecting of disease mechanisms
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