Emission excitation cross sections are recorded for collisions between Xe
2+
+ O
2
and O
+
+ Xe over a collision energy range of approximately 2 to 900 eV in the center-of-mass (
E
cm
) frame. ...Emissive products of the O
+
+ Xe reaction are examined in the 700-1000 nm optical range and include neutral atomic oxygen emissions and neutral xenon emissions. Atomic emission products of the O
+
+ Xe collision appear to have measureable cross sections near
E
cm
= 14 eV and increase in intensity until about
E
cm
= 60 eV where they remain approximately constant for the remainder of the measured collision energies. For the Xe
2+
+ O
2
collision system, O
2
+
charge transfer products are measured through fluorescence of the O
2
+
(A-X) and (b-a) manifolds over the 200-850 nm window. Total cross sections for both manifolds do not vary beyond the experimental precision at all measured energies. Vibrational populations are derived from a fitting of the experimental data. The populations are found to deviate from a Franck-Condon distribution at all collision energies and appear to be well-modeled within a multi-channel Landau-Zener framework over the collision energy range measured.
Vibrational state collision energy dependence of Xe/O collision systems.
Emission excitation cross sections are recorded for collisions between Xe2+ + O2 and O+ + Xe over a collision energy range of approximately 2 to 900 eV in the center-of-mass (Ecm) frame. Emissive ...products of the O+ + Xe reaction are examined in the 700–1000 nm optical range and include neutral atomic oxygen emissions and neutral xenon emissions. Atomic emission products of the O+ + Xe collision appear to have measureable cross sections near Ecm = 14 eV and increase in intensity until about Ecm = 60 eV where they remain approximately constant for the remainder of the measured collision energies. For the Xe2+ + O2 collision system, O2+ charge transfer products are measured through fluorescence of the O2+(A–X) and (b–a) manifolds over the 200–850 nm window. Total cross sections for both manifolds do not vary beyond the experimental precision at all measured energies. Vibrational populations are derived from a fitting of the experimental data. The populations are found to deviate from a Franck–Condon distribution at all collision energies and appear to be well-modeled within a multi-channel Landau–Zener framework over the collision energy range measured.
Abstract The COVID‐19 pandemic drastically altered human social systems. To better understand ramifications of the pandemic for aquatic scientists, we assessed perceptions of mentorship within the ...Association for the Sciences of Limnology and Oceanography, focusing on impacts felt during the pandemic. We also evaluated current preferences and practices (e.g., valued traits, network composition, communication tools) related to mentoring, as a way of gauging change within the community and informing ongoing or future resilience and recovery efforts. In surveying this group, we found the largest pandemic related professional development gaps to be lost opportunities for mentoring, the absence of in‐person meetings, and missed collegial/collaborative interactions. We also assessed which mentorship characteristics were highly valued and found that, “communicative” was the most consistently valued characteristic. Finally, we assessed mentor network composition and code of conduct use. Findings show a limited range of disciplines within most mentees' networks, suggesting lack of access to mentors in outside fields or disciplines, and widespread valuation of codes of conduct but limited implementation. We advocate for mentoring practices that foster personal connections, expand networks, and develop clear plans for mentoring relationships, as a path toward general improvement and resilience within mentoring networks in the face of disruption.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The peroxisome proliferator activated receptors PPARα, PPARγ, and PPARδ are ligand-activated transcription factors that play a key role in lipid homeostasis. The fibrates raise circulating levels of ...high-density lipoprotein cholesterol and lower levels of triglycerides in part through their activity as PPARα agonists; however, the low potency and restricted selectivity of the fibrates may limit their efficacy, and it would be desirable to develop more potent and selective PPARα agonists. Modification of the selective PPARδ agonist 1 (GW501516) so as to incorporate the 2-aryl-2-methylpropionic acid group of the fibrates led to a marked shift in potency and selectivity toward PPARα agonism. Optimization of the series gave 25a, which shows EC50 = 4 nM on PPARα and at least 500-fold selectivity versus PPARδ and PPARγ. Compound 25a (GW590735) has been progressed to clinical trials for the treatment of diseases of lipid imbalance.
Background
With over 5.1 million individuals, the Puerto Rican population makes up over 1.5% of the US population and is the 2nd largest Hispanic/Latino population in the continental US. There are an ...estimated of 60,000 cases of AD on the island. The Puerto Rico Alzheimer's and Related Dementias Initiatives (PRADI) cohort will both leverage and complement existing AD Resources, the Alzheimer Disease Sequencing Project (ADSP) with the inclusion of a diverse and underrepresented population. At present, the cohort consists of a total of 935 total participants including individuals from 115 multiplex AD families. There are 418 cases of dementia, 217 mild cognitive impairment, and 300 unrelated and family‐based controls.
Method
We examined the most successful strategy to recruit cases and controls as well as multiplex families for both case/control and family‐based genetic studies. We began by engaging a wide range of stakeholders across the island. The core activities of our team include relationship building, partnership development and maintenance, and coalition building. For the community outreach, we utilize mass media like newspapers, radio interviews, and focal group presentations and engaged the following stakeholder groups: Alzheimer disease day care centers, elderly housing in San Juan, senior day care centers, non‐profit organizations, private neurology offices, and other community‐based organizations such as the Alzheimer’s Association.
Result
The percent of patients recruited through each stakeholder group were 45.76% (428/935) from community outreach, 34.33% (321/935) from private neurologist practices, 18.93% (177/935) from senior day care centers and 0.96% (9/935) from Alzheimer disease day care centers. The mean age and standard deviation of cases and controls were 78.22 years (±9.37) and 70.84 years (±7.92) respectively. Examining the data with respect to multiplex family structure, we found that 53.77% of the families (including the largest families) came from private physician referral.
Conclusion
Partnering with diverse stakeholders and building coalitions proved to be effective as an outreach method for recruitment. Private physicians remain an excellent source for the identification of multiplex AD families for family‐based genetics study. Outreach community‐based approaches are highly successful mechanisms to educate and engage participants in genetic research.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Abstract
Background
Alzheimer’s disease (AD) has become a burden of social and economic importance, affecting millions of families and society at large. The Puerto Rico Alzheimer and Related ...Dementias Initiatives (PRADI) cohort was developed to investigate AD and genetics factors of AD in the Puerto Rican population. PRADI recruitment was a snowball sampling, with both island‐wide geographic distribution, as well as extensions to PR communities in the continental US. In this study we assessed the relationship between AD and cardiovascular risk factors of AD in the PR population.
Method
We assessed over 700 elderly PR individuals for dementia, as well as medical history. Affection status was assessed using standard AD clinical criteria (NINCDS‐ADRDA) or mild cognitive impairment. All medical history was obtained by a self‐report or informant report. Differences between affected and unaffected were initially tested using a chi‐square test (for sex, diabetes, hypercholesterolemia, heart disease, hypertension, and stroke) and a t‐test for the age of the exam. Follow‐up analyses on stroke were performed using logistic regression with age at exam and sex as covariates in the model.
Result
The analysis revealed no differences sex differences between AD and unaffected (p‐value > 0.05). Similarly, affected and unaffected showed similar levels of type 2 diabetes, hypercholesterolemia, heart disease, and hypertension (p‐value > 0.05). Affected individuals did however show an increase in stroke incidence (14.0% vs 5.2%; p‐value = 8.3e‐5). This difference persisted even when controlling for age of exam and sex. We did see a difference in age of exam between cases and controls, but this is likely due to ascertainment scheme.
Conclusion
This analysis suggests that stroke may be a contributing factor to dementia in the PR population. However, given biases in the ascertainment scheme, additional assessments need to be performed. Additionally, work is ongoing to assess the role of ancestry and genetic factors in this association.
Full text
Available for:
FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Abstract
Background
With over 5.1 million individuals, the Puerto Rican population makes up over 1.5% of the US population and is the 2nd largest Hispanic/Latino population in the continental US. ...There are an estimated of 60,000 cases of AD on the island. The Puerto Rico Alzheimer's and Related Dementias Initiatives (PRADI) cohort will both leverage and complement existing AD Resources, the Alzheimer Disease Sequencing Project (ADSP) with the inclusion of a diverse and underrepresented population. At present, the cohort consists of a total of 935 total participants including individuals from 115 multiplex AD families. There are 418 cases of dementia, 217 mild cognitive impairment, and 300 unrelated and family‐based controls.
Method
We examined the most successful strategy to recruit cases and controls as well as multiplex families for both case/control and family‐based genetic studies. We began by engaging a wide range of stakeholders across the island. The core activities of our team include relationship building, partnership development and maintenance, and coalition building. For the community outreach, we utilize mass media like newspapers, radio interviews, and focal group presentations and engaged the following stakeholder groups: Alzheimer disease day care centers, elderly housing in San Juan, senior day care centers, non‐profit organizations, private neurology offices, and other community‐based organizations such as the Alzheimer’s Association.
Result
The percent of patients recruited through each stakeholder group were 45.76% (428/935) from community outreach, 34.33% (321/935) from private neurologist practices, 18.93% (177/935) from senior day care centers and 0.96% (9/935) from Alzheimer disease day care centers. The mean age and standard deviation of cases and controls were 78.22 years (±9.37) and 70.84 years (±7.92) respectively. Examining the data with respect to multiplex family structure, we found that 53.77% of the families (including the largest families) came from private physician referral.
Conclusion
Partnering with diverse stakeholders and building coalitions proved to be effective as an outreach method for recruitment. Private physicians remain an excellent source for the identification of multiplex AD families for family‐based genetics study. Outreach community‐based approaches are highly successful mechanisms to educate and engage participants in genetic research.
Full text
Available for:
FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Background
Alzheimer’s disease (AD) has become a burden of social and economic importance, affecting millions of families and society at large. The Puerto Rico Alzheimer and Related Dementias ...Initiatives (PRADI) cohort was developed to investigate AD and genetics factors of AD in the Puerto Rican population. PRADI recruitment was a snowball sampling, with both island‐wide geographic distribution, as well as extensions to PR communities in the continental US. In this study we assessed the relationship between AD and cardiovascular risk factors of AD in the PR population.
Method
We assessed over 700 elderly PR individuals for dementia, as well as medical history. Affection status was assessed using standard AD clinical criteria (NINCDS‐ADRDA) or mild cognitive impairment. All medical history was obtained by a self‐report or informant report. Differences between affected and unaffected were initially tested using a chi‐square test (for sex, diabetes, hypercholesterolemia, heart disease, hypertension, and stroke) and a t‐test for the age of the exam. Follow‐up analyses on stroke were performed using logistic regression with age at exam and sex as covariates in the model.
Result
The analysis revealed no differences sex differences between AD and unaffected (p‐value > 0.05). Similarly, affected and unaffected showed similar levels of type 2 diabetes, hypercholesterolemia, heart disease, and hypertension (p‐value > 0.05). Affected individuals did however show an increase in stroke incidence (14.0% vs 5.2%; p‐value = 8.3e‐5). This difference persisted even when controlling for age of exam and sex. We did see a difference in age of exam between cases and controls, but this is likely due to ascertainment scheme.
Conclusion
This analysis suggests that stroke may be a contributing factor to dementia in the PR population. However, given biases in the ascertainment scheme, additional assessments need to be performed. Additionally, work is ongoing to assess the role of ancestry and genetic factors in this association.
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Available for:
FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The ApoE epsilon4 allele is the most significant genetic risk factor for late-onset Alzheimer disease. The risk conferred by epsilon4, however, differs across populations, with populations of African ...ancestry showing lower epsilon4 risk compared to those of European or Asian ancestry. The cause of this heterogeneity in risk effect is currently unknown; it may be due to environmental or cultural factors correlated with ancestry, or it may be due to genetic variation local to the ApoE region that differs among populations. Exploring these hypotheses may lead to novel, population-specific therapeutics and risk predictions. To test these hypotheses, we analyzed ApoE genotypes and genome-wide array data in individuals from African American and Puerto Rican populations. A total of 1,766 African American and 220 Puerto Rican individuals with late-onset Alzheimer disease, and 3,730 African American and 169 Puerto Rican cognitively healthy individuals (> 65 years) participated in the study. We first assessed average ancestry across the genome ("global" ancestry) and then tested it for interaction with ApoE genotypes. Next, we assessed the ancestral background of ApoE alleles ("local" ancestry) and tested if ancestry local to ApoE influenced Alzheimer disease risk while controlling for global ancestry. Measures of global ancestry showed no interaction with ApoE risk (Puerto Rican: p-value = 0.49; African American: p-value = 0.65). Conversely, ancestry local to the ApoE region showed an interaction with the ApoE epsilon4 allele in both populations (Puerto Rican: p-value = 0.019; African American: p-value = 0.005). ApoE epsilon4 alleles on an African background conferred a lower risk than those with a European ancestral background, regardless of population (Puerto Rican: OR = 1.26 on African background, OR = 4.49 on European; African American: OR = 2.34 on African background, OR = 3.05 on European background). Factors contributing to the lower risk effect in the ApoE gene epsilon4 allele are likely due to ancestry-specific genetic factors near ApoE rather than non-genetic ethnic, cultural, and environmental factors.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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