41 research outputs found
Genetic Determinants For Cancer Risks With Racial Differences And Asthma
Over the past decade, many studies have found disproportionally higher prostate cancer among men of African ancestry, and testicular cancer incidences among men of European ancestry, compared with men from other ethnicity/race groups. However, genetic determinants that could potentially explain this observation are unclear. This study collected single nucleotide polymorphisms (SNPs) related to the two cancer types and compared the frequencies of each risk allele of SNPs among men of African or European ancestry from several genetic databases. When comparing the frequencies of risk alleles that are associated with prostate and testicular cancers, significant differences were found between those of African descendants and European descendants. As the second part of this thesis, we investigated the roles of genetic in the reversal relationship observed between asthma and all cancer risks. Single Nucleotide Polymorphisms that were reported to be associated with asthma were collected and identified first and the cancer risks related to each variant were reviewed in the hope to provide genetic basis for future pathway analysis
Connecting shear localization with the long-range correlated polarized stress fields in granular materials
One long-lasting puzzle in amorphous solids is shear localization, where
local plastic deformation involves cooperative particle rearrangements in small
regions of a few inter-particle distances, self-organizing into shear bands and
eventually leading to the material failure. Understanding the connection
between the structure and dynamics of amorphous solids is essential in physics,
material sciences, geotechnical and civil engineering, and geophysics. Here we
show a deep connection between shear localization and the intrinsic structures
of internal stresses in an isotropically jammed granular material subject to
shear. Specifically, we find strong (anti)correlations between the micro shear
bands and two polarized stress fields along two directions of maximal shear. By
exploring the tensorial characteristics and the rotational symmetry of force
network, we reveal that such profound connection is a result of symmetry
breaking by shear. Finally, we provide the solid experimental evidence of
long-range correlated inherent shear stress in an isotropically jammed granular
system.Comment: 23 pages, 9 figure
Distinct elastic properties and their origins in glasses and gels
Glasses and gels, widely encountered amorphous solids with diverse industrial
and everyday applications, share intriguing similarities such as rigidity
without crystalline order and dynamic slowing down during aging. However, the
underlying differences between these two fascinating materials have remained
elusive. Here we uncover distinct elastic properties concerning observation and
aging times in glasses and gels, while delving into the underlying mechanisms.
In glasses, we observe a gradual decrease in the shear modulus, while the bulk
modulus remains constant throughout the observation time. In contrast, gels
exhibit a decrease in both the shear and bulk moduli over the observation time.
Additionally, during aging, glasses exhibit a steady trend of stiffening, while
gels demonstrate initial stiffening followed by softening. By unravelling the
intricate relationship between structure, dynamics, and elasticity, we
attribute these differences to mechanisms that minimize free energy: structural
ordering in glasses and interface reduction in gels. Our work not only uncovers
the distinct behaviors of glasses and gels but also sheds light on the origin
and evolution of elasticity in non-equilibrium disordered solids, offering
significant implications for the application and design of amorphous materials.Comment: 15 pages, 5 figures, 5 Supplementary Figure
Experimental evidence of detailed balance in granular systems
The principle of detailed balance (DB) states that every kinetic transition
in a system with many micro-states, , is balanced, on average, with the
opposite transition, . Since its introduction by
Boltzmann, this principle has been used by luminaries, such as Einstein,
Eddington, Kramers, Pauli, Ehrenfest, Dirac, Onsager, and many others to derive
significant results that underpin much of our scientific understanding. The
current belief is that DB is satisfied only in equilibrium systems, while
non-equilibrium steady states can only be balanced by cycles, such as . We show here experimentally that DB can exist and is commonly and
robustly satisfied in a family of quasi-statically cyclically sheared granular
systems. We further study the approach to DB as a function of system size and
time. Given the significant impact that this principle has had on equilibrium
systems, we believe that this discovery paves the way for better models of the
dynamics of non-equilibrium systems.Comment: 5 pages, 4 figure
West Hartford-Bloomfield Health District Community Needs Assessment: A Mixed Methods Study Identifying COVID-19 Knowledge, Perceptions, and Health Disparities
Background: The West Hartford-Bloomfield Health District (WHBHD) is a regional health department serving the towns of West Hartford and Bloomfield in Connecticut. From February to April of 2020, elderly and Black residents accounted for 59% and 38% of COVID-19 related deaths, respectively. Since the district has not assessed community health needs previously and is interested in becoming accredited, a community needs assessment will serve as the first step in implementing effective and timely interventions to address needs, disparities, and misperceptions about the pandemic.
Methods: A comprehensive survey was adapted from existing NIH COVID-19 research instruments. 779 responses were collected on the topics of community health and COVID-19 knowledge, practices and perceptions. Five semi-structured key informant interviews were conducted with faith-based organizations and local government leaders to corroborate findings from the survey. Quantitative analyses were performed via SAS and R, and qualitative data was summarized.
Results: Demographic distributions significantly differed between West Hartford and Bloomfield in age, income, race, marital status and household size. While there were differences in community health problems, social/environmental problems, and health care barriers, both towns shared individual health problems and perceived certain populations as most underserved. Both towns have adequate COVID-19 knowledge regarding symptoms and transmissions, low perceived risk of infection, and positive attitude towards preventative actions and measures. There were significant differences in COVID-19 testing accessibility between towns (p = 0.002), with nearly double the proportion of West Hartford residents reporting difficulty accessing testing. COVID-19 vaccination status is also different between towns, with both reporting lack of available vaccines as the primary reason preventing or delaying vaccination.
Conclusions: The mixed methods approach to conducting this community needs assessment has provided consequential preliminary findings that will be useful in refining the health district’s current and future responses to COVID-19 and other public health issues.https://elischolar.library.yale.edu/ysph_pbchrr/1055/thumbnail.jp
A review on shear jamming
Jamming is a ubiquitous phenomenon that appears in many soft matter systems,
including granular materials, foams, colloidal suspensions, emulsions,
polymers, and cells -- when jamming occurs, the system undergoes a transition
from flow-like to solid-like states. Conventionally, the jamming transition
occurs when the system reaches a threshold jamming density under isotropic
compression, but recent studies reveal that jamming can also be induced by
shear. Shear jamming has attracted much interest in the context of
non-equilibrium phase transitions, mechanics and rheology of amorphous
materials. Here we review the phenomenology of shear jamming and its related
physics. We first describe basic observations obtained in experiments and
simulations, and results from theories. Shear jamming is then demonstrated as a
"bridge" that connects the rheology of athermal soft spheres and thermal hard
spheres. Based on a generalized jamming phase diagram, a universal description
is provided for shear jamming in frictionless and frictional systems. We
further review the isostaticity and criticality of the shear jamming
transition, and the elasticity of shear jammed solids. The broader relevance of
shear jamming is discussed, including its relation to other phenomena such as
shear hardening, dilatancy, fragility, and discrete shear thickening.Comment: 19 pages, 9 figure
HandBooster: Boosting 3D Hand-Mesh Reconstruction by Conditional Synthesis and Sampling of Hand-Object Interactions
Reconstructing 3D hand mesh robustly from a single image is very challenging,
due to the lack of diversity in existing real-world datasets. While data
synthesis helps relieve the issue, the syn-to-real gap still hinders its usage.
In this work, we present HandBooster, a new approach to uplift the data
diversity and boost the 3D hand-mesh reconstruction performance by training a
conditional generative space on hand-object interactions and purposely sampling
the space to synthesize effective data samples. First, we construct versatile
content-aware conditions to guide a diffusion model to produce realistic images
with diverse hand appearances, poses, views, and backgrounds; favorably,
accurate 3D annotations are obtained for free. Then, we design a novel
condition creator based on our similarity-aware distribution sampling
strategies to deliberately find novel and realistic interaction poses that are
distinctive from the training set. Equipped with our method, several baselines
can be significantly improved beyond the SOTA on the HO3D and DexYCB
benchmarks. Our code will be released on
https://github.com/hxwork/HandBooster_Pytorch
Gender-Specific and U-Shaped Relationship Between Serum Uric Acid and All-Cause Mortality Among Chinese Older Adults: A National Population-Based Longitudinal Study
Objectives: This study aimed to prospectively investigate gender-specific relationship between hyperuricemia and all-cause mortality among Chinese older adults.Methods: The study was based on the Chinese Longitudinal Healthy Longevity Survey (CLHLS) 2008–2018, a prospective nationwide cohort of older adults in China. Multivariate Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% CIs for all-cause mortality. Restricted cubic splines (RCS) were conducted to explore the dose-response relationship between SUA levels and all-cause mortality.Results: For older women, compared to the participants in the third quartile of SUA level, those in the highest quartile of SUA was associated with significantly higher risk of all-cause mortality in the fully adjusted model (HR: 1.41, 95% CI: 1.03–1.92). No significant associations between SUA levels and all-cause mortality were observed in older men. The present study further found a U-shaped non-linear relationship between SUA levels and all-cause mortality in both sexes of older population (P for non-linear <0.05).Conclusions: This study provided prospective epidemiological evidence for the predictive role of SUA on all-cause mortality among the Chinese aging population over 10 years of follow-up, while revealing considerable gender-related differences