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"Johnson, Laura"
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Exploring factors associated with pregnant women’s experiences of material hardship during COVID-19: a cross-sectional Qualtrics survey in the United States
2021
Background
The COVID-19 pandemic has exacerbated the financial insecurity of women and their families globally. Some studies have explored the impact of financial strain among pregnant women, in particular, during the pandemic. However, less is known about the factors associated with pregnant women’s experiences of material hardship.
Methods
This cross-sectional study used a non-probability sample to examine the factors associated with pregnant women’s experiences of material hardship during the COVID-19 pandemic. In January 2021, 183 pregnant women living in the United States participated in an online Qualtrics panel survey. In addition to socio-demographic characteristics, individuals were asked about their finances and predictors of financial well-being, mental health symptoms, and intimate partner violence (IPV) experiences. Chi-square analysis and one-way ANOVA were used to examine whether women’s experiences with material hardship and associated factors differed by income level (i.e., less than $20,000; $20,000 to $60,000; more than $60,000). Ordinary least squares regression was used to calculate unadjusted and adjusted estimates.
Results
Study findings showed that the majority of women in the sample experienced at least one form of material hardship in the past year. Individuals with an annual household income less than $20,000 reported the highest average number of material hardships experienced (
M
= 3.7,
SD
= 2.8). Compared to women with household incomes less than $20,000, women with incomes of more than $60,000 reported significantly fewer material hardships, less financial strain, and higher levels of financial support, economic self-efficacy, and economic-self-sufficiency. Women with incomes of $60,000 or more also reported significantly lower levels of psychological abuse, and a smaller percentage met the cut-off for anxiety. Economic self-sufficiency, financial strain, posttraumatic stress disorder, and economic abuse were all significantly associated with material hardship.
Conclusions
A contribution of this study is that it highlights the significant, positive association between economic abuse, a unique form of IPV, and material hardship among pregnant women during the pandemic. These findings suggest the need for policy and practice interventions that help to ameliorate the financial insecurity experienced by some pregnant women, as well as respond to associated bidirectional vulnerabilities (e.g., mental health symptoms, experiences of IPV).
Journal Article
Driving gene-engineered T cell immunotherapy of cancer
2017
Chimeric antigen receptor (CAR) gene-engineered T cell therapy holds the potential to make a meaningful differ- ence in the lives of patients with terminal cancers. For decades, cancer therapy was based on biophysical parameters, with surgical resection to debulk, followed by radiation and chemotherapy to target the rapidly growing tumor cells, while mostly sparing quiescent normal tissues. One breakthrough occurred with allogeneic bone-marrow transplant for patients with leukemia, which provided a sometimes curative therapy. The field of adoptive cell therapy for sol- id tumors was established with the discovery that tumor-infiltrating lymphocytes could be expanded and used to treat and even cure patients with metastatic melanoma. Tumor-specific T-cell receptors (TCRs) were identified and engineered into patient peripheral blood lymphocytes, which were also found to treat tumors. However, these were limited by patient HLA-restriction. Close behind came generation of CAR, combining the exquisite recognition of an antibody with the effector function of a T cell. The advent of CD19-targeted CARs for treating patients with multiple forms of advanced B-cell malignancies met with great success, with up to 95% response rates. Applying CAR treat- ment to solid tumors, however, has just begun, but already certain factors have been made clear: the tumor target is of utmost importance for clinicians to do no harm; and solid tumors respond differently to CAR therapy compared with hematologic ones. Here we review the state of clinical gene-engineered T cell immunotherapy, its successes, chal- lenges, and future.
Journal Article
Supercolonial structure of invasive populations of the tawny crazy ant Nylanderia fulva in the US
by
Eyer, Pierre-André
,
Johnson, Laura N. L.
,
Calcaterra, Luis A.
in
Aggression
,
Aggressive behavior
,
Aggressiveness
2018
Background
Social insects are among the most serious invasive pests in the world, particularly successful at monopolizing environmental resources to outcompete native species and achieve ecological dominance. The invasive success of some social insects is enhanced by their unicolonial structure, under which the presence of numerous queens and the lack of aggression against non-nestmates allow high worker densities, colony growth, and survival while eliminating intra-specific competition. In this study, we investigated the population genetics, colony structure and levels of aggression in the tawny crazy ant,
Nylanderia fulva
, which was recently introduced into the United States from South America.
Results
We found that this species experienced a genetic bottleneck during its invasion lowering its genetic diversity by 60%. Our results show that the introduction of
N. fulva
is associated with a shift in colony structure. This species exhibits a multicolonial organization in its native range, with colonies clearly separated from one another, whereas it displays a unicolonial system with no clear boundaries among nests in its invasive range. We uncovered an absence of genetic differentiation among populations across the entire invasive range, and a lack of aggressive behaviors towards conspecifics from different nests, even ones separated by several hundreds of kilometers.
Conclusions
Overall, these results suggest that across its entire invasive range in the U.S.A., this species forms a single supercolony spreading more than 2000 km. In each invasive nest, we found several, up to hundreds, of reproductive queens, each being mated with a single male. The many reproductive queens per nests, together with the free movement of individuals between nests, leads to a relatedness coefficient among nestmate workers close to zero in introduced populations, calling into question the stability of this unicolonial system in which indirect fitness benefits to workers is apparently absent.
Journal Article
Examining the impact of economic abuse on survivors of intimate partner violence: a scoping review
2022
Background
Economic abuse is a unique form of intimate partner violence (IPV) and includes behaviors that control a survivor’s ability to acquire, use, and maintain resources. These tactics can result in someone becoming economically dependent on their partner and may limit their ability to leave the relationship and establish independence. The aim of this study was to conduct a scoping review focused on the impact of economic abuse on survivors of IPV.
Methods
A total of 14 databases were reviewed, which resulted in 35 peer-reviewed manuscripts for inclusion in the study. Manuscripts were included if they were: written in English, published since the year 2000, focused specifically on the impact of economic abuse perpetrated by an intimate partner, economic abuse was measured as an independent variable, and if economic abuse was looked at separately from other forms of IPV. Both convenience and population-based samples were included in the review. Information was extracted using a data charting form. The data were analyzed using a combination of grouping techniques and constant comparison methods to identify key findings.
Results
Studies found significant associations between economic abuse and a range of outcomes, such as mental and physical health, financial impacts, parent-child interactions, and quality of life. The most frequently examined were mental health, followed by financial issues.
Conclusions
Limitations of these studies included a lack of longitudinal research and a focus on heterosexual relationships with male-perpetrated violence toward female survivors. Study findings highlight the wide-ranging potential impacts of economic abuse on survivors and the need for additional research to better understand potential outcomes and implement and evaluate interventions to address them.
Journal Article
Bridgehead effect and multiple introductions shape the global invasion history of a termite
by
Wang, Changlu
,
Pierre-André, Eyer
,
Johnson Laura N L
in
Bayesian analysis
,
Biology
,
Demography
2021
Native to eastern Asia, the Formosan subterranean termite Coptotermes formosanus (Shiraki) is recognized as one of the 100 worst invasive pests in the world, with established populations in Japan, Hawaii and the southeastern United States. Despite its importance, the native source(s) of C. formosanus introductions and their invasive pathway out of Asia remain elusive. Using ~22,000 SNPs, we retraced the invasion history of this species through approximate Bayesian computation and assessed the consequences of the invasion on its genetic patterns and demography. We show a complex invasion history, where an initial introduction to Hawaii resulted from two distinct introduction events from eastern Asia and the Hong Kong region. The admixed Hawaiian population subsequently served as the source, through a bridgehead, for one introduction to the southeastern US. A separate introduction event from southcentral China subsequently occurred in Florida showing admixture with the first introduction. Overall, these findings further reinforce the pivotal role of bridgeheads in shaping species distributions in the Anthropocene and illustrate that the global distribution of C. formosanus has been shaped by multiple introductions out of China, which may have prevented and possibly reversed the loss of genetic diversity within its invasive range.Blumenfeld and Eyer et al. retrace the invasion history of the termite Coptotermes formosansus from eastern Asia to the US using approximate Bayesian computation. They find a complex invasion history, with multiple introductions originating from eastern Asia, as well as a bridgehead introduction originating from Hawaii, which appears to have mitigated the loss of genetic diversity within the invasive US range.
Journal Article
The histone methyltransferase SETDB1 is recurrently amplified in melanoma and accelerates its onset
by
Lin, William M.
,
Young, Richard A.
,
Zon, Leonard I.
in
692/420/2489/68
,
692/699/67/1813/1634
,
Age of Onset
2011
Oncogenes
BRAF(V600E)
and
SETDB1
in melanoma
Transgenic zebrafish carrying the human oncogene
BRAF(V600E)
, the most common mutation in melanoma patients, provide a convenient model for melanoma. Two papers from Leonard Zon and colleagues demonstrate the potential of this system in the study of cancer genetics and in drug development. Ceol
et al
. screen for genes that cooperate with mutated
BRAF
, and identify
SETDB1
as capable of accelerating melanoma formation in fish. The gene is found in a region that is frequently amplified in human melanomas, and its gene product, SETDB1, is a histone methylating enzyme that is often overexpressed in those melanomas. This work establishes
SETDB1
as an important oncogene. White
et al
. find expression of a gene signature in melanoma-susceptible zebrafish embryos that is indicative of disrupted differentiation of neural crest progenitors. A chemical screen identifies leflunomide, an immunomodulatory drug used to treat rheumatoid arthritis, as an inhibitor of neural crest stem cells. Leflunomide has antimelanoma activity in human melanoma xenografts and might prove useful as an anticancer drug, particularly in combination with BRAF inhibitors.
Using a zebrafish model of melanoma, this study has searched for genes that can cooperate with mutated BRAF, a frequent oncogenic event in human melanomas. It is found that SETDB1 can accelerate melanoma formation in fish and resides in a region frequently amplified in human melanomas. SETDB1, a histone methylating enzyme, is also frequently overexpressed in human melanomas and functions at least in part by regulating the expression of
HOX
genes.
The most common mutation in human melanoma,
BRAF(V600E)
, activates the serine/threonine kinase BRAF and causes excessive activity in the mitogen-activated protein kinase pathway
1
,
2
.
BRAF(V600E)
mutations are also present in benign melanocytic naevi
3
, highlighting the importance of additional genetic alterations in the genesis of malignant tumours. Such changes include recurrent copy number variations that result in the amplification of oncogenes
4
,
5
. For certain amplifications, the large number of genes in the interval has precluded an understanding of the cooperating oncogenic events. Here we have used a zebrafish melanoma model to test genes in a recurrently amplified region of chromosome 1 for the ability to cooperate with
BRAF(V600E)
and accelerate melanoma. SETDB1, an enzyme that methylates histone H3 on lysine 9 (H3K9), was found to accelerate melanoma formation significantly in zebrafish. Chromatin immunoprecipitation coupled with massively parallel DNA sequencing and gene expression analyses uncovered genes, including
HOX
genes, that are transcriptionally dysregulated in response to increased levels of SETDB1. Our studies establish
SETDB1
as an oncogene in melanoma and underscore the role of chromatin factors in regulating tumorigenesis.
Journal Article
On the (A)dS decoupling limits of massive gravity
by
Johnson, Laura A.
,
Hinterbichler, Kurt
,
de Rham, Claudia
in
Classical and Quantum Gravitation
,
Classical Theories of Gravity
,
Coupling
2018
A
bstract
We consider various decoupling limits of ghost-free massive gravity on (A)dS. The first is a decoupling limit on AdS space where the mass goes to zero while the AdS radius is held fixed. This results in an interacting massive Proca vector theory with a Λ
2
∼ (
M
Pl
m
)
1/2
strong coupling scale which is ghost-free by construction and yet can not be put in the form of the generalized Proca theories considered so far. We comment on the existence of a potential duality between this Proca theory and a CFT on the boundary. The second decoupling limit we consider is a new limit on dS, obtained by sending the mass towards the finite partially massless value. We do this by introducing the scalar Stückelberg field which restores the partially massless symmetry. For generic values of the parameters, only a finite number of operators enter the partially massless decoupling limit and take the form of dS Galileons. If the interactions are chosen to be precisely those of the ‘candidate’ non-linear partially massless theory, the resulting strong coupling scale has a higher value and the resulting decoupling limit includes an infinite number of interactions which we give in closed form. These interactions preserve both the linear partially massless symmetry and the dS version of the Galileon shift symmetry.
Journal Article
Constraints on a massive double-copy and applications to massive gravity
by
Johnson, Laura A.
,
Paranjape, Shruti
,
Jones, Callum R. T.
in
Amplitudes
,
Classical and Quantum Gravitation
,
Classical Theories of Gravity
2021
A
bstract
We propose and study a BCJ double-copy of massive particles, showing that it is equivalent to a KLT formula with a kernel given by the inverse of a matrix of massive bi-adjoint scalar amplitudes. For models with a uniform non-zero mass spectrum we demonstrate that the resulting double-copy factors on physical poles and that up to at least 5-particle scattering, color-kinematics duality satisfying numerators always exist. For the scattering of 5 or more particles, the procedure generically introduces spurious singularities that must be cancelled by imposing additional constraints. When massive particles are present, color-kinematics duality
is not enough
to guarantee a physical double-copy. As an example, we apply the formalism to massive Yang-Mills and show that up to 4-particle scattering the double-copy construction generates physical amplitudes of a model of dRGT massive gravity coupled to a dilaton and a two-form with dilaton parity violating couplings. We show that the spurious singularities in the 5-particle double-copy do not cancel in this example, and the construction fails to generate physically sensible amplitudes. We conjecture sufficient constraints on the mass spectrum, which in addition to massive BCJ relations, guarantee the absence of spurious singularities.
Journal Article
Population Genetic Structure Within and among Seasonal Site Types in the Little Brown Bat (Myotis lucifugus) and the Northern Long-Eared Bat (M. septentrionalis)
by
Johnson, Laura N. L.
,
Burns, Lynne E.
,
Frasier, Timothy R.
in
Analysis
,
Animal behavior
,
Animal Migration - physiology
2015
During late summer and early autumn, temperate bats migrate from their summering sites to swarming sites, where mating likely occurs. However, the extent to which individuals of a single summering site migrate to the same swarming site, and vice versa, is not known. We examined the migratory connectivity between summering and swarming sites in two temperate, North American, bat species, the little brown bat (Myotis lucifugus) and the northern long-eared bat (Myotis septentrionalis). Using mitochondrial and microsatellite DNA markers, we examined population structuring within and among summering and swarming sites. Both species exhibited moderate degrees of mitochondrial DNA differentiation (little brown bat: FST(SUMMER) = 0.093, FST(SWARMING) = 0.052; northern long-eared bat: FST(SUMMER) = 0.117, FST(SWARMING) = 0.043) and little microsatellite DNA differentiation among summering and among swarming sites[corrected]. Haplotype diversity was significantly higher at swarming sites than summering sites, supporting the idea that swarming sites are comprised of individuals from various summering sites. Further, pairwise analyses suggest that swarming sites are not necessarily comprised of only individuals from the most proximal summering colonies.
Journal Article
Shift-symmetric spin-1 theories
by
Hinterbichler, Kurt
,
Bonifacio, James
,
Johnson, Laura A.
in
Broken symmetry
,
Classical and Quantum Gravitation
,
CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS
2019
A
bstract
We study interacting massive spin-1 theories in de Sitter (dS) and anti-de Sitter (AdS) space that possess shift symmetries parametrized by (A)dS Killing vectors. We show how they emerge from the massless limit of massive spin-2 theories on (A)dS space. In the case of massive gravity, the corresponding spin-1 theory realizes a symmetry breaking pattern that takes two copies of the (A)dS isometry group down to a diagonal subgroup. By taking the flat space limit of this theory, we find a new symmetry of the decoupling limit of massive gravity in flat space. This symmetry acts on the vector modes, is parametrize by an antisymmetric tensor, and fixes the nonlinear structure of the scalar-vector sector of the decoupling limit.
Journal Article