Every longest circuit of a 3-connected, K3,3K_{3,3}-minor free graph has a chord

Carsten Thomassen conjectured that every longest circuit in a 3-connected graph has a chord. We prove the conjecture for graphs having no $K_{3,3}$ minor, and consequently for planar graphs.Comment: accepted by Journal of Graph Theor

Let Care Shine Through

Care is in the eyes of the receiver; it doesn\u27t exist unless those being cared for experience it. The authors describe culturally relevant critical teacher care, an approach that considers the effects of students\u27 cultural and socioeconomic conditions and that helps teachers find ways to show care to every learner—especially those from oppressed groups. Bondy and Hambacher describe three principles of this care for students (having political clarity, embodying critical hope, and sticking to asset-based thinking). They describe four helpful practices that they observed in a long-term study of two effective 5th grade teachers. These teachers embodied a culturally relevant approach to supporting students: expanding the meaning of achievement; overhauling deficit thinking; offering high expectations and support; and teaching with urgency

Designing Redress: A Study About Grievances Against Public Bodies

How grievances against public bodies are resolved is important not only for the individuals concerned and the decision-makers complained about but also to the whole system of government. People need to have confidence that when things go wrong, they will be put right. There is a general public interest in that being done in accordance with constitutional principles and in ways that are effective and efficient. Over many years, a great variety of different ?mechanisms? for dealing with grievances have been created, ranging from internal complaints processes through to the work of external bodies (including ombudsmen, tribunals and courts). This project has focused on how mechanisms are designed. The study explores how different mechanisms can be thought of as relating to each other. It also looks at the various reasons why mechanisms have to be designed. Drawing on interviews with people involved in the design process and analysis of public information, a map of where the activity of designing redress has been created. Evaluating the ?administrative justice landscape?, two particular deficiencies emerge: there is no strong political or official leadership in relation to how mechanisms ought to be designed and the system is fragmented, with many different people, in various organisations all contributing to design activities. Might a toolkit of guiding principles for designing redress be one way of achieving a better design process and outcomes? A number of principles are proposed in this report, and the authors hope to engage stakeholders in a debate about how this might best be taken forward

Increased oxidative stress, inflammation, and glutamate: Potential preventive and therapeutic targets for hearing disorders.

Hearing disorders constitute one of the major health concerns in the USA. Decades of basic and clinical studies have identified numerous ototoxic agents and investigated their modes of action on the inner ear, utilizing tissue culture as well as animal and human models. Current preventive and therapeutic approaches are considered unsatisfactory. Therefore, additional modalities should be developed. Many studies suggest that increased levels of oxidative stress, chronic inflammation, and glutamate play an important role in the initiation and progression of damage to the inner ear leading to hearing impairments. To prevent these cellular deficits, antioxidants, anti-inflammatory agents, and antagonists of glutamate receptor have been used individually or in combination with limited success. It is essential, therefore, to simultaneously enhance the levels of antioxidant enzymes by activating the Nrf2 (a nuclear transcriptional factor) pathway, dietary and endogenous antioxidant compounds, and B12-vitamins in order to reduce the levels of oxidative stress, chronic inflammation, and glutamate at the same time. This review presents evidence to show that increased levels of these cellular metabolites, biochemical or factors are involved in the pathogenesis of cochlea leading to hearing impairments. It presents scientific rationale for the use of a mixture of micronutrients that may decrease the levels of oxidative damage, chronic inflammation, and glutamate at the same time. The benefits for using oral administration of proposed micronutrient mixture in humans are presented. Animal and limited human studies indirectly suggest that orally administered micronutrients can accumulate in the inner ear. Therefore, this route of administration may be useful in prevention, and in combination with standard care, in improved management of hearing problems following exposure to well-recognized and studied ototoxic agents, such as noise, cisplatin, aminoglycoside antibiotics, and advanced age

Ore- and Fan-type heavy subgraphs for Hamiltonicity of 2-connected graphs

Bedrossian characterized all pairs of forbidden subgraphs for a 2-connected graph to be Hamiltonian. Instead of forbidding some induced subgraphs, we relax the conditions for graphs to be Hamiltonian by restricting Ore- and Fan-type degree conditions on these induced subgraphs. Let $G$ be a graph on $n$ vertices and $H$ be an induced subgraph of $G$. $H$ is called \emph{o}-heavy if there are two nonadjacent vertices in $H$ with degree sum at least $n$, and is called $f$-heavy if for every two vertices $u,v\in V(H)$, $d_{H}(u,v)=2$ implies that $\max\{d(u),d(v)\}\geq n/2$. We say that $G$ is $H$-\emph{o}-heavy ($H$-\emph{f}-heavy) if every induced subgraph of $G$ isomorphic to $H$ is \emph{o}-heavy (\emph{f}-heavy). In this paper we characterize all connected graphs $R$ and $S$ other than $P_3$ such that every 2-connected $R$-\emph{f}-heavy and $S$-\emph{f}-heavy ($R$-\emph{o}-heavy and $S$-\emph{f}-heavy, $R$-\emph{f}-heavy and $S$-free) graph is Hamiltonian. Our results extend several previous theorems on forbidden subgraph conditions and heavy subgraph conditions for Hamiltonicity of 2-connected graphs.Comment: 21 pages, 2 figure

Unique Breast Cancer Features Within the Vietnamese Population

BACKGROUND: Breast cancer is known to be a heterogeneous disease across women, and even within individual tumors. However, relatively little is known about heterogeneity across cultures. There has been some evidence to suggest that Asian women are more likely to have HER2+ breast cancer than their Caucasian counterparts. PURPOSE: The aim of this study was to further investigate the unique pattern of breast cancer incidence and subtype in the Vietnamese population. METHODS: We retrospectively collected data on all Vietnamese women diagnosed with invasive breast cancer at the Lester & Sue Smith Breast Center in Houston, Texas over a four year period. We recorded the subtype of breast cancer, tumor grade, age at diagnosis, and menopausal status for each woman. We then compared these characteristics between our population of Vietnamese breast cancer patients, and an ethnically diverse group of American women from the 2010 SEER registry. RESULTS: We discovered that 15 of 33 Vietnamese patients diagnosed in our breast center had HER2 over-expressing breast cancer, resulting in a 45% rate of HER2 positivity. Compared with the 2010 Surveillance, Epidemiology, and End Results (SEER) registry data that encompasses 28% of all US breast cancer patients diagnosed that year, regardless of race, the Smith Clinic Vietnamese cohort had a statistically significant higher rate of HER2+ breast cancer, with an odds ratio of 4.7 (45% vs. 15%, p CONCLUSIONS: Vietnamese breast cancer patients, especially those older than 50 years old, tend to have higher rates of HER2+ breast cancer than the general population. This unique pattern of breast cancer merits further study, as it may reflect a genetic mutation or environmental exposure which is more common among Vietnamese women

Gerechte Designs with Rectangular Regions

A \emph{gerechte framework} is a partition of an $n \times n$ array into $n$ regions of $n$ cells each. A \emph{realization} of a gerechte framework is a latin square of order $n$ with the property that when its cells are partitioned by the framework, each region contains exactly one copy of each symbol. A \emph{gerechte design} is a gerechte framework together with a realization. We investigate gerechte frameworks where each region is a rectangle. It seems plausible that all such frameworks have realizations, and we present some progress towards answering this question. In particular, we show that for all positive integers $s$ and $t$, any gerechte framework where each region is either an $s \times t$ rectangle or a $t\times s$ rectangle is realizable.Comment: 14 pages, 12 figure

Distinctive cellular response to aluminum based adjuvants.

Aluminum-based adjuvants (ABAs) are used in human vaccines to enhance the magnitude of protective immune responses elicited against specific pathogens. One hypothesis is that stress signals released by aluminum-exposed necrotic cells play a role in modulating an immune response that contributes to the adjuvant's effectiveness. We hypothesized that aluminum adjuvant-induced necrosis would be similar irrespective of cellular origin or composition of the adjuvant. To test this hypothesis, human macrophages derived from peripheral monocytic cell line (THP-1) and cells derived from the human brain (primary astrocytes) were evaluated. Three commercially available formulations of ABAs (Alhydrogel, Imject alum, and Adju-Phos) were examined. Alum was also used as a reference. Cell viability, reactive oxygen species formation, and production of tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) were quantified. Cells were exposed to different concentrations (10-100 μg/mL) of the adjuvants for 24 h or 72 h. The two FDA approved adjuvants (Alhydrogel and Adju-Phos) decreased cell viability in both cell types. At the 72 h time point, the decrease in viability was accompanied with increased ROS formation. The size of the aluminum agglomerates was not relatable to the changes observed. After exposure to ABAs, astrocytes and macrophages presented a distinct profile of cytokine secretion which may relate to the function and unique characteristics of each cell type. These variations indicate that aluminum adjuvants may have differing capability of activating cells of different origin and thus their utility in specific vaccine design should be carefully assessed for optimum efficacy

The epistemic approach to argument evaluation: Virtues, beliefs, commitments

This paper will have two parts. In the first, it will point out the agreement between lists of paradigm epistemic and argumentative virtues, and it will take that agreement as prima facie support for the epistemic approach to argument evaluation. Second, it will consider the disagreement over whether successful argument resolution requires change of belief or whether it only requires change of commitment. It turns out that the epistemic approach is neutral on that question

Becoming warm demanders: Perspectives and practices of first-year teachers

In the literature on culturally responsive pedagogy warm demanders are teachers who embrace values and enact practices that are central to their students’ success. Few scholars have examined the experience of novice teachers who attempt to enact this stance. In this study of two first-year, female, European American teachers who attempted to be warm demanders for their predominantly African American elementary school students, the authors answer the question, “How do the teachers think about and enact warm demanding?” The teachers’ contrasting experiences have implications for administrators and teacher educators