76 research outputs found
Finding twin smooth integers by solving Pell equations
Any pair of consecutive B-smooth integers for a given smoothness bound B
corresponds to a solution (x, y) of the equation x^2 - 2Dy^2 = 1 for a certain
square-free, B-smooth integer D and a B-smooth integer y. This paper describes
algorithms to find such twin B-smooth integers that lie in a given interval by
using the structure of solutions of the above Pell equation. The problem of
finding such twin smooth integers is motivated by the quest for suitable
parameters to efficiently instantiate recent isogeny-based cryptosystems. While
the Pell equation structure of twin B-smooth integers has previously been used
to describe and compute the full set of such pairs for very small values of B,
increasing B to allow for cryptographically sized solutions makes this approach
utterly infeasible. We start by revisiting the Pell solution structure of the
set of twin smooth integers. Instead of using it to enumerate all twin smooth
pairs, we focus on identifying only those that lie in a given interval. This
restriction allows us to describe algorithms that navigate the vast set of Pell
solutions in a more targeted way. Experiments run with these algorithms have
provided examples of twin B-smooth pairs that are larger and have smaller
smoothness bound B than previously reported pairs. Unfortunately, those
examples do not yet provide better parameters for cryptography, but we hope
that our methods can be generalized or used as subroutines in future work to
achieve that goal
Mechanical Characterization of Human Brain Tissue and SoftDynamic Gels Exhibiting Electromechanical Neuro-Mimicry
Synthetic hydrogels are an important class of materialsin tissue engineering, drug delivery, and other biomedicalfields. Their mechanical and electrical properties can betuned to match those of biological tissues. In this work,we report on hydrogels that exhibit both mechanical andelectrical biomimicry. The presented dual networks consistof supramolecular networks formed from 2:1 homoternarycomplexes of imidazolium-based guest molecules in cucu-bit[8]uril and covalent networks of oligoethylene glycol-(di)methacrylate. We also investigate the viscoelastic prop-erties of human brain tissues. The mechanical properties ofthe dual network gels are benchmarked against the humantissue, and we find that they both are neuro-mimetic and ex-hibit cytocompatiblity in a neural stem cell model.The Winston Churchill Foundation of the United States.
The Newton International Fellowship
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Cucurbit[8]uril-derived graphene hydrogels
The scalable production of uniformly distributed graphene (GR)-based composite materials remains a sizable challenge. While GR-polymer nanocomposites can be manufactured at large scale, processing limitations result in poor control over the homogeneity of hydrophobic GR sheets in the matrices. Such processes often result in difficulties controlling stability and avoiding aggregation, therefore eliminating benefits that might have otherwise arisen from the nanoscopic dimensions of GR. Here, we report an exfoliated and stabilized GR dispersion in water. Cucurbit[8]uril (CB[8])-mediated host guest chemistry was used to obtain supramolecular hydrogels consisting of uniformly distributed GR and guest-functionalized macromolecules. The obtained GR-hydrogels show superior bioelectrical properties over identical systems produced without CB[8]. Utilizing such supramolecular interactions with biologically-derived macromolecules is a promising approach to stabilize graphene in water and avoid oxidative chemistry.Marie Sklodowska-Curie individual research grant (H2020-MSCAIF-
2017, P.ID: 797106)
The Winston Churchill Foundation of the United States
EPSRC Doctoral Training Grant EP/N509620/1
EPSRC Programme Grant NOtCH (EP/L027151/1
Assessment of changes in quality of life among patients in the SAVE Study - Sirolimus as therapeutic Approach to uVEitis: a randomized study to assess the safety and bioactivity of intravitreal and subconjunctival injections of sirolimus in patients with non-infectious uveitis.
BACKGROUND: The National Eye Institute 39-Question Visual Function Questionnaire (NEI VFQ-39) is an indicator of vision-related quality of life (QoL). The NEI VFQ-39 is used to assess the QoL in patients with non-infectious posterior uveitis, intermediate uveitis, or panuveitis, treated with subconjunctival (SCJ) or intravitreal (IVT) sirolimus as an immunomodulatory therapeutic (IMT) agent, delivered subconjunctivally (SCJ) or intravitreally (IVT) (the SAVE Study). Thirty subjects with non-infectious uveitis were randomized (SCJ:IVT, 1:1) for a prospective clinical trial. The 39-Question Visual Function Questionnaire (VFQ-39) was administered at baseline (BL), month 6 (M6), and month 12 (M12) visits. The survey measures self-reported vision health status for patients with chronic eye disease and assesses the effects of visual impairment on both task-oriented visual function and general health domains. In accordance to the NEI-VFQ Manual, each patient\u27s questionnaire was converted to a scaled score between 0 (worst) and 100 (best), and median scores were calculated for each of the subcategories and overall composite score at BL, M6, and M12. Wilcoxon signed-rank test was performed.
RESULTS: Twenty-six patients completed the VFQ-39 at BL and M6, whereas 23 patients completed it at M12. Patients showed a significant improvement in pooled composite scores from BL to M6 and BL to M12. Analysis by treatment groups showed that intravitreal injection of sirolimus is better tolerated.
CONCLUSIONS: Sirolimus has demonstrated bioactivity as an IMT and corticosteroid-sparing agent to treat non-infectious uveitis. Patients receiving intravitreal injection of sirolimus showed overall improvement of vision-related health while those receiving subconjunctival injections did not. Larger randomized control trials with sirolimus are indicated to validate these results.
TRIAL REGISTRATION: ClinicalTrials.gov: NCT00908466
The First Flight of the Marshall Grazing Incidence X-ray Spectrometer (MaGIXS)
The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) sounding rocket
experiment launched on July 30, 2021 from the White Sands Missile Range in New
Mexico. MaGIXS is a unique solar observing telescope developed to capture X-ray
spectral images, in the 6 - 24 Angstrom wavelength range, of coronal active
regions. Its novel design takes advantage of recent technological advances
related to fabricating and optimizing X-ray optical systems as well as
breakthroughs in inversion methodologies necessary to create spectrally pure
maps from overlapping spectral images. MaGIXS is the first instrument of its
kind to provide spatially resolved soft X-ray spectra across a wide field of
view. The plasma diagnostics available in this spectral regime make this
instrument a powerful tool for probing solar coronal heating. This paper
presents details from the first MaGIXS flight, the captured observations, the
data processing and inversion techniques, and the first science results.Comment: 20 pages, 18 figure
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SCIPP: An Expanded Community of Practice - Community Publishing
SCIPP redefines and expands the existing notions about what makes for a vibrant and robust community of practice by partnering CSUSB students and professors with K-12 students, parents, and educators, along with committed community partners. SCIPP encourages curiosity in ways that leads to critical thinking, exploration, risk taking , confidence building, open-mindedness, and other personal traits that equip them with the softskills to be active, critical, and creative contributors to our communities. SCIPP pedagogy embraces our students\u27 collective wisdom and focuses on relational building where multi-directional communication is promoted and students are viewed as equal stakeholders in their own educations. SCIPP puts collaboration into action which in turn fosters community-based lifelong learning. SCIPP provides the open intellectual space for future university students (our K-12 students) to engage with existing university students in meaningful ways so as to sustain interconnected partnerships facilitating community engagement. It supports parents as experts in the education of their children and acknowledges parents as the first conduits to spark their children’s imagination while they actively participate in education enriching activities and programs. Everyone involved is committed to creating a secure and open atmosphere for dreaming, sharing, and learning. Together we explore the aspects of community publishing through collaborative learning in formal and informal settings relating to digital and printed medias
The First Flight of the Marshall Grazing Incidence X-Ray Spectrometer (MaGIXS)
The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) sounding rocket experiment launched on 2021 July 30 from the White Sands Missile Range in New Mexico. MaGIXS is a unique solar observing telescope developed to capture X-ray spectral images of coronal active regions in the 6–24 Å wavelength range. Its novel design takes advantage of recent technological advances related to fabricating and optimizing X-ray optical systems, as well as breakthroughs in inversion methodologies necessary to create spectrally pure maps from overlapping spectral images. MaGIXS is the first instrument of its kind to provide spatially resolved soft X-ray spectra across a wide field of view. The plasma diagnostics available in this spectral regime make this instrument a powerful tool for probing solar coronal heating. This paper presents details from the first MaGIXS flight, the captured observations, the data processing and inversion techniques, and the first science results
Proceedings of the 3rd Biennial Conference of the Society for Implementation Research Collaboration (SIRC) 2015: advancing efficient methodologies through community partnerships and team science
It is well documented that the majority of adults, children and families in need of evidence-based behavioral health interventionsi do not receive them [1, 2] and that few robust empirically supported methods for implementing evidence-based practices (EBPs) exist. The Society for Implementation Research Collaboration (SIRC) represents a burgeoning effort to advance the innovation and rigor of implementation research and is uniquely focused on bringing together researchers and stakeholders committed to evaluating the implementation of complex evidence-based behavioral health interventions. Through its diverse activities and membership, SIRC aims to foster the promise of implementation research to better serve the behavioral health needs of the population by identifying rigorous, relevant, and efficient strategies that successfully transfer scientific evidence to clinical knowledge for use in real world settings [3]. SIRC began as a National Institute of Mental Health (NIMH)-funded conference series in 2010 (previously titled the “Seattle Implementation Research Conference”; $150,000 USD for 3 conferences in 2011, 2013, and 2015) with the recognition that there were multiple researchers and stakeholdersi working in parallel on innovative implementation science projects in behavioral health, but that formal channels for communicating and collaborating with one another were relatively unavailable. There was a significant need for a forum within which implementation researchers and stakeholders could learn from one another, refine approaches to science and practice, and develop an implementation research agenda using common measures, methods, and research principles to improve both the frequency and quality with which behavioral health treatment implementation is evaluated. SIRC’s membership growth is a testament to this identified need with more than 1000 members from 2011 to the present.ii SIRC’s primary objectives are to: (1) foster communication and collaboration across diverse groups, including implementation researchers, intermediariesi, as well as community stakeholders (SIRC uses the term “EBP champions” for these groups) – and to do so across multiple career levels (e.g., students, early career faculty, established investigators); and (2) enhance and disseminate rigorous measures and methodologies for implementing EBPs and evaluating EBP implementation efforts. These objectives are well aligned with Glasgow and colleagues’ [4] five core tenets deemed critical for advancing implementation science: collaboration, efficiency and speed, rigor and relevance, improved capacity, and cumulative knowledge. SIRC advances these objectives and tenets through in-person conferences, which bring together multidisciplinary implementation researchers and those implementing evidence-based behavioral health interventions in the community to share their work and create professional connections and collaborations
Anthony Vigil, 19th Annual ODU Literary Festival
Anthony R Vigil, born and raised in Denver, Colorado, is a Chicano poet and activist who tutors and educates barrio youth in the areas of Mexicano/Chicano Studies and Literature. Through his experience with his sisters and brothers of the barrio, he identifies the arts, specifically, poetry, as the epicenter for liberating revolutionary social change for Mexicano/Chicano youth. As such, his Chicanoetry and los wordshopz often lowride him to jive [juvenile] hall, recreation centers, street corners, detention centers, and to Mexicano/Chicano youth conferences. Because of his poetry of witness and protest in the urban barrios, he has been unofficially banned from speaking and reading at numerous public schools in Denver. Although his first manuscript of poetry, The Obsidian Ranfla, is yet unpublished, his poems have been placed in the Mid-American Review, The Dry Creek Review, Tonatiuh-Quinto Sol, The Heartlands Today, El Mexica, and Struggle. His largo poema, La Boda Chicana: Globeville, Color Azlan won a 1994 AWP Intro Award in poetry
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