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1.
J Public Health Dent ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953889

RESUMO

OBJECTIVE: American Indian and Alaska native (AI/AN) individuals report distrust of the healthcare system. This study explored associations between having either high levels of dental distrust or high levels of dental care-related fear and anxiety ("dental anxiety") and oral health outcomes in AI/AN adults. METHODS: The 2022 State of Oral Health Equity in America survey included the Modified Dental Anxiety Scale and asked to what extent respondents agreed with the statement, "At my last oral health visit, I trusted the oral health provider I saw", and asked about self-rated oral health and presence of a dental home. RESULTS: AI/AN individuals (N = 564) who reported low dental trust (n = 110) or with high dental anxiety (MDAS≥19; n = 113) reported significantly worse overall and oral health and were significantly less likely to have a dental home (p < 0.05 used for each analysis). CONCLUSION: Dental distrust and dental anxiety can significantly impact oral health and dental utilization in AI/AN communities and are important intervention targets to improve AI/AN oral health.

2.
Rev Sci Instrum ; 95(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38958513

RESUMO

3D asymmetries are major degradation mechanisms in inertial-confinement fusion implosions at the National Ignition Facility (NIF). These asymmetries can be diagnosed and reconstructed with the neutron imaging system (NIS) on three lines of sight around the NIF target chamber. Conventional tomographic reconstructions are used to reconstruct the 3D morphology of the implosion using NIS [Volegov et al., J. Appl. Phys. 127, 083301 (2020)], but the problem is ill-posed with only three imaging lines of sight. Asymmetries can also be diagnosed with the real-time neutron activation diagnostics (RTNAD) and the neutron time-of-flight (nToF) suite. Since the NIS, RTNAD, and nToF each sample a different part of the implosion using different physical principles, we propose that it is possible to overcome the limitations of too few imaging lines of sight by performing 3D reconstructions that combine information from all three heterogeneous data sources. This work presents a new machine learning-based reconstruction technique to do just this. By using a simple physics model and group of neural networks to map 3D morphologies to data, this technique can easily account for data of multiple different types. A simple proof-of-principle is presented, demonstrating that this technique can accurately reconstruct a hot-spot shape using synthetic primary neutron images and a hot-spot velocity vector. In particular, the hot-spot's asymmetry, quantified as spherical harmonic coefficients, is reconstructed to within ±4% of the radius in 90% of test cases. In the future, this technique will be applied to actual NIS, RTNAD, and nToF data to better understand 3D asymmetries at the NIF.

3.
Ther Adv Infect Dis ; 11: 20499361241256290, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827952

RESUMO

Background: Syphilis is a serious global public health challenge. Despite prior progress in syphilis control, incidence has been increasing in recent years. Syphilis is a common coinfection among people living with HIV (PLHIV). In Panama, few data describe syphilis prevalence among PLHIV. We describe syphilis antibody and high-titer (⩾1:8) active syphilis prevalence and associated factors among individuals who attended an antiretroviral clinic. Methods: A cross-sectional study was undertaken during February-March 2022 and September-October 2022 for adults (⩾18 year) assigned male and female at birth, respectively. Participants provided peripheral blood samples and self-administered a questionnaire. Samples were screened using immunochromatography; antibody-positive samples were tested using rapid plasma regain to 1:512 dilutions. Logistic regression was used to identify factors associated with syphilis antibody and high-titer active syphilis. Results: In all, 378 participants gave blood samples; 377 individuals participated in the questionnaire (216 self-reported male sex [males], 158 female [females], and three intersex individuals). Median age was 36 years (interquartile range: 28-45 years). Overall, syphilis antibody prevalence was 32.3% (122/378) (males, 50.7% [108/2013]; females, 5.7% [9/158]; intersex individuals, 100.0% (3/3)], p < 0.01. High-titer active syphilis was found among 24.6% (n = 30) of samples with positive antibody test (males 27.8% [n = 30], females 0.0% [0/9], intersex individuals 0.0% [0/3]). Antibody positivity was associated in the multivariable model with males (50.7%, AOR = 24.6, 95%CI: 1.57-384.53). High-titer active syphilis was associated with younger participant age (18-30 years, 13.2%, OR = 4.82, 95%CI: 1.17-19.83); 31-40 years, 7.8%, OR = 4.24, 95%CI: 1.04-17.21 versus 3.2% >40 years), homosexual identity (16.0% OR = 34.2, 95%CI: 4.50-259.27 versus 0.6% among heterosexual identity); in the multivariable model, associated with sexual identity (bisexual 19.1%, AOR = 10.89, 95%CI: 1.00-119.06) compared to heterosexual identity (0.6%) and weakly associated with concurrency (⩾1 ongoing sexual relationships, 15.9%, AOR = 3.09, 95%CI: 0.94-10.14). Conclusion: This study found very high prevalence of syphilis antibodies and high-titer syphilis among PLHIV in Panama. Those most affected are males, younger in age, those who practice concurrent sexual relationships, and those who reported homosexual and bisexual identity. Targeted interventions should include repetitive testing and treatment, especially among individuals who may be at increased infection risk.


Prevalence of syphilis among people living with HIV who attend a large antiretroviral therapy clinic, Panama, 2022 Syphilis is a significant health challenge worldwide. On a global scale, yearly syphilis incidence is increasing, including in Panama. However, there are no current data to explain syphilis prevalence and who is most affected among people living with HIV in Panama. In order to understand syphilis in Panama and create targeted interventions among specific groups of people, it is important to describe how many people are infected, and who is most affected by this infection. Therefore, we conducted a study among 378 people living with HIV at a treatment clinic in Panama City, Panama. Blood samples and demographic data were collected. In all, syphilis antibodies were found in 32.3% of individuals (50.7% of those who self-report as males, 5.7% as females, and 100% of those who self-report as intersex. Of those with positive antibody tests, 24.6% of individuals also had active syphilis. Only individuals who identify as male had active syphilis. Our findings show high syphilis prevalence among people with HIV in Panama City, particularly among males, those who are younger, those who report sexual identity as homosexual or bisexual, and those with ongoing sexual relationships with more than one individual. Targeted interventions are needed among people living with HIV, especially among the groups most affected. These interventions could include testing more often for syphilis and providing timely treatment, especially among individuals who may be at increased risk of infection.

4.
Adv Neurobiol ; 35: 157-182, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38874723

RESUMO

Pain, fear, stress, and anxiety are separate yet interrelated phenomena. Each of these concepts has an extensive individual body of research, with some more recent work focusing on points of conceptual overlap. The role of the endogenous opioid system in each of these phenomena is only beginning to be examined and understood. Research examining the ways in which endogenous opioids (e.g., beta-endorphin; ßE) may mediate the relations among pain, fear, stress, and anxiety is even more nascent. This chapter explores the extant evidence for endogenous opioid activity as an underpinning mechanism of these related constructs, with an emphasis on research examining ßE.


Assuntos
Ansiedade , Medo , Dor , Estresse Psicológico , Animais , Humanos , Ansiedade/metabolismo , beta-Endorfina/metabolismo , Medo/fisiologia , Peptídeos Opioides/metabolismo , Dor/psicologia , Dor/metabolismo , Estresse Psicológico/metabolismo
5.
J Hum Hypertens ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926521

RESUMO

Racial and sexual orientation discrimination may exacerbate the double epidemic of hypertension (HTN) and HIV that affects men of color who have sex with men (MSM). This was a cross-sectional analysis of African American, Asian American, Native Hawaiian, or Pacific Islander (NHPI) MSM living with HIV (PLWH) cohort in Honolulu and Philadelphia. Racial and sexual orientation discrimination, stress, anxiety, and depression were measured with computer-assisted self-interview questionnaires (CASI). We examined the associations between racial and sexual orientation discrimination with hypertension measured both in the office and by 24-h ambulatory blood pressure monitoring (ABPM) using multivariable logistic regression. Sixty participants (60% African American, 18% Asian, and 22% NHPI) completed CASIs and 24-h ABPM. African American participants (80%) reported a higher rate of daily racial discrimination than Asian American (36%) and NHPI participants (17%, p < 0.001). Many participants (51%) reported daily sexual orientation discrimination. Sixty-six percent of participants had HTN by office measurement and 59% had HTN by 24-h ABPM measurement. Participants who experienced racial discrimination had greater odds of having office-measured HTN than those who did not, even after adjustment (Odds Ratio 5.0 (95% Confidence Interval [1.2-20.8], p = 0.03)). This association was not seen with 24-h ABPM. Hypertension was not associated with sexual orientation discrimination. In this cohort, MSM of color PLWH experience significant amounts of discrimination and HTN. Those who experienced racial discrimination had higher in-office blood pressure. This difference was not observed in 24-h APBM and future research is necessary to examine the long-term cardiovascular effects.

6.
Cell Host Microbe ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38942027

RESUMO

Gut microbiota influence anti-tumor immunity, often by producing immune-modulating metabolites. However, microbes consume a variety of metabolites that may also impact host immune responses. We show that tumors grow unchecked in the omenta of microbe-replete mice due to immunosuppressive Tregs. By contrast, omental tumors in germ-free, neomycin-treated mice or mice colonized with altered Schaedler's flora (ASF) are spontaneously eliminated by CD8+ T cells. These mice lack Proteobacteria capable of arginine catabolism, causing increases in serum arginine that activate the mammalian target of the rapamycin (mTOR) pathway in Tregs to reduce their suppressive capacity. Transfer of the Proteobacteria, Escherichia coli (E. coli), but not a mutant unable to catabolize arginine, to ASF mice reduces arginine levels, restores Treg suppression, and prevents tumor clearance. Supplementary arginine similarly decreases Treg suppressive capacity, increases CD8+ T cell effectiveness, and reduces tumor burden. Thus, microbial consumption of arginine alters anti-tumor immunity, offering potential therapeutic strategies for tumors in visceral adipose tissue.

7.
Ther Adv Infect Dis ; 11: 20499361241249657, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38751756

RESUMO

Background: Cognitive decline among people living with HIV (PLWH) is growing concern as world populations become increasing older including higher proportions of PLWH. It is vitally important to understand psychosocial predictors of age-related cognitive decline men who have sex with men (MSM) living with HIV. Objectives: The current study seeks to examine psychosocial risk factors the contribute to the risk of age-related cognitive impairment as measured by Cardiovascular Risk Factors, Aging, and Incidence of Dementia (CAIDE) score in a racially diverse sample of MSM living with HIV. Design: The present analysis utilizes data from the baseline (n = 196) and 6-month follow-up (n = 135) time points of a longitudinal cohort study of PLWH. Methods: Using a self-report survey, we examine the associations between psychosocial predictors (e.g. trauma, mental health, chronic pain, sleep disturbance, etc.) and risk of dementia using the CAIDE risk score. Analyses include linear and logistic regression. Results: In adjusted model stress, chronic pain, Black racial identity, and having a sexual identity that is bisexual or another category are all positively associated with CAIDE scores. Childhood sexual abuse history was negatively associated with CAIDE scores indicating a protective effect. Sleep disorder has a positive association with CAIDE scores after adjusting for the baseline CAIDE scores. Conclusion: These results indicate modifiable correlates of cognitive risk (stress and chronic pain). Interventions should seek to address these comorbid factors including the consideration of minority stress and stigma. Interventions should seek to reach Black and bisexual men living with HIV, including possible cultural tailoring to interventions and messaging. Lastly, future research should examine the impact of variation within childhood sexual abuse histories to better understand their association with cognitive impairment later in life. This may include considering the nature, severity, and potential treatment of trauma symptoms.


What makes middle-aged or older people who have HIV more likely to have memory problems later in life? We asked a racially diverse group of gay and bisexual men who have HIV. Why was the study done? Older people are becoming a larger portion of our communities including older people living with HIV. It's important to understand what makes older people more likely to have memory problems as they age including older people living with HIV. What did the researchers do? We asked 196 middle-aged and older adults who have HIV to answer questions about their health including things that we know might make them more likely to have memory problems later in life. What did the researchers find? We found that having more stress or reoccurring pain was related to being more likely to have memory problems later in life. People who have trouble sleeping were more likely to have memory problems later in life. We also found that Black people were more likely to have memory problems later in life. People who had been abused sexually as children were less likely to have memory problems later in life. What do the findings mean? These findings help us understand things that may make someone more likely to have memory problems later in life. These include things that could be changed like reoccurring pain and troubles sleeping. It also highlighted that Black people may need more support to prevent memory problems later in life.

8.
Faraday Discuss ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38807494

RESUMO

Sulfur atoms serve as key players in diverse chemical processes, from astrochemistry at very low temperature to combustion at high temperature. Building upon our prior findings, showing cyclization to thiophenes following the reaction of ground-state sulfur atoms with dienes, we here extend this investigation to include many additional reaction products, guided by detailed theoretical predictions. The outcomes highlight the complex formation of products during intersystem crossing (ISC) to the singlet surfaces. Here, we employed crossed-beam velocity map imaging and high-level ab initio methods to explore the reaction of S(3P) with 1,3-butadiene and isoprene under single-collision conditions and in low-temperature flows. For the butadiene reaction, our experimental results show the formation of thiophene via H2 loss, a 2H-thiophenyl radical through H loss, and thioketene through ethene loss at a slightly higher collision energy compared to previous observations. Complementary Chirped-Pulse Fourier-Transform mmWave spectroscopy (CP-FTmmW) measurements in a uniform flow confirmed the formation of thioketene in the reaction at 20 K. For the isoprene reaction, we observed analogous products along with the 2H-thiophenyl radical arising from methyl loss and C3H4S (loss of ethene or H2 + acetylene). CP-FTmmW detected the formation of thioformaldehyde via loss of 1,3-butadiene, again in the 20 K flow. Coupled-cluster calculations on the pathways found by the automated kinetic workflow code KinBot support these findings and indicate ISC to the singlet surface, leading to the generation of various long-lived intermediates, including 5-membered heterocycles.

9.
Microorganisms ; 12(5)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38792844

RESUMO

Along with the standard therapies for glioblastoma, patients are commonly prescribed trimethoprim-sulfamethoxazole (TMP-SMX) and dexamethasone for preventing infections and reducing cerebral edema, respectively. Because the gut microbiota impacts the efficacy of cancer therapies, it is important to understand how these medications impact the gut microbiota of patients. Using mice that have been colonized with human microbiota, this study sought to examine how TMP-SMX and dexamethasone affect the gut microbiome. Two lines of humanized microbiota (HuM) Rag1-/- mice, HuM1Rag and HuM2Rag, were treated with either TMP-SMX or dexamethasone via oral gavage once a day for a week. Fecal samples were collected pre-treatment (pre-txt), one week after treatment initiation (1 wk post txt), and three weeks post-treatment (3 wk post txt), and bacterial DNA was analyzed using 16S rRNA-sequencing. The HuM1Rag mice treated with TMP-SMX had significant shifts in alpha diversity, beta diversity, and functional pathways at all time points, whereas in the HuM2Rag mice, it resulted in minimal changes in the microbiome. Likewise, dexamethasone treatment resulted in significant changes in the microbiome of the HuM1Rag mice, whereas the microbiome of the HuM2Rag mice was mostly unaffected. The results of our study show that routine medications used during glioblastoma treatment can perturb gut microbiota, with some microbiome compositions being more sensitive than others, and these treatments could potentially affect the overall efficacy of standard-of-care therapy.

10.
Life (Basel) ; 14(5)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38792577

RESUMO

Bacteroides vulgatus and Bacteroides uniformis are known to be abundant in the human fecal microbial community. Although these strains typically remain stable over time in humans, disruption of this microbial community following antibiotics resulted in the transient change to new strains suggesting that a complex, dynamic strain community exists in humans. To further study the selection of dominant fecal microbial strains from the gastrointestinal tract (GIT) community, we analyzed three longitudinal metagenomic sequencing data sets using BLAST+ to identify genes encoding Bacteroidales-specific antimicrobial proteins (BSAP) that have known functions to restrict species-specific replication of B. uniformis (BSAP-2) or B. vulgatus (BSAP-3) and have been postulated to provide a competitive advantage in microbial communities. In the HMP (Human Microbiome Project) data set, we found fecal samples from individuals had B. vulgatus or B. uniformis with either complete or deleted BSAP genes that did not change over time. We also examined fecal samples from two separate longitudinal data sets of individuals who had been given either single or multiple antibiotics. The BSAP gene pattern from most individuals given either single or multiple antibiotics recovered to be the same as the pre-antibiotic strain. However, in a few individuals, we found incomplete BSAP-3 genes at early times during the recovery that were replaced by B. vulgatus with the complete BSAP-3 gene, consistent with the function of the BSAP to specifically restrict Bacteroides spp. The results of these studies provide insights into the fluxes that occur in the Bacteroides spp. GIT community following perturbation and the dynamics of the selection of a dominant fecal strain of Bacteroides spp.

11.
Nat Commun ; 15(1): 2975, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582938

RESUMO

Indirect Drive Inertial Confinement Fusion Experiments on the National Ignition Facility (NIF) have achieved a burning plasma state with neutron yields exceeding 170 kJ, roughly 3 times the prior record and a necessary stage for igniting plasmas. The results are achieved despite multiple sources of degradations that lead to high variability in performance. Results shown here, for the first time, include an empirical correction factor for mode-2 asymmetry in the burning plasma regime in addition to previously determined corrections for radiative mix and mode-1. Analysis shows that including these three corrections alone accounts for the measured fusion performance variability in the two highest performing experimental campaigns on the NIF to within error. Here we quantify the performance sensitivity to mode-2 symmetry in the burning plasma regime and apply the results, in the form of an empirical correction to a 1D performance model. Furthermore, we find the sensitivity to mode-2 determined through a series of integrated 2D radiation hydrodynamic simulations to be consistent with the experimentally determined sensitivity only when including alpha-heating.

12.
J Am Chem Soc ; 146(19): 13282-13295, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38687970

RESUMO

We present a detailed study of the time-dependent photophysics and photochemistry of a known conformation of the two protonated pentapeptides Leu-enkephalin (Tyrosine-Glycine-Glycine-Phenylalanine-Leucine, YGGFL) and its chromophore-swapped analogue FGGYL, carried out under cryo-cooled conditions in the gas phase. Using ultraviolet-infrared (UV-IR) double resonance, we record excited state IR spectra as a function of time delay between UV and IR pulses. We identify unique Tyr OH stretch transitions due to the S1 state and the vibrationally excited triplet state(s) formed by intersystem crossing, Tn(v). Photofragment mass spectra are recorded out of the S1 origin and following UV-IR double resonance. Several competing site-specific fragmentation pathways are discovered involving peptide backbone cleavage, Tyr side chain loss, and N-terminal NH3 loss mediated by electron transfer. In YGGFL, IR excitation in the S1 state promotes electron transfer (ET) from the aromatic ring to the N-terminal R-NH3+ group leading to loss of neutral NH3. This product channel is missing in FGGYL due to the larger distance for ET from Y(4) to NH3+. Selective loss of the Tyr side chain occurs out of an excited state process following UV excitation and is further enhanced by IR excitation in S1 and Tn(v) states of both YGGFL and FGGYL. Finally, IR excitation in the S1 or Tn(v) states fragments the peptide backbone exclusively at amide(4), producing the b4 cation. We postulate that this selective fragmentation results from intersystem crossing to produce vibrationally excited triplets with enough energy to launch the proton along a proton conduit present in the known starting structure.


Assuntos
Processos Fotoquímicos , Prótons , Espectrofotometria Infravermelho , Peptídeos/química , Encefalina Leucina/química
13.
Proc Natl Acad Sci U S A ; 121(18): e2317690121, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38648485

RESUMO

The underlying mechanism(s) by which the PML::RARA fusion protein initiates acute promyelocytic leukemia is not yet clear. We defined the genomic binding sites of PML::RARA in primary mouse and human hematopoietic progenitor cells with V5-tagged PML::RARA, using anti-V5-PML::RARA chromatin immunoprecipitation sequencing and CUT&RUN approaches. Most genomic PML::RARA binding sites were found in regions that were already chromatin-accessible (defined by ATAC-seq) in unmanipulated, wild-type promyelocytes, suggesting that these regions are "open" prior to PML::RARA expression. We found that GATA binding motifs, and the direct binding of the chromatin "pioneering factor" GATA2, were significantly enriched near PML::RARA binding sites. Proximity labeling studies revealed that PML::RARA interacts with ~250 proteins in primary mouse hematopoietic cells; GATA2 and 33 others require PML::RARA binding to DNA for the interaction to occur, suggesting that binding to their cognate DNA target motifs may stabilize their interactions. In the absence of PML::RARA, Gata2 overexpression induces many of the same epigenetic and transcriptional changes as PML::RARA. These findings suggested that PML::RARA may indirectly initiate its transcriptional program by activating Gata2 expression: Indeed, we demonstrated that inactivation of Gata2 prior to PML::RARA expression prevented its ability to induce self-renewal. These data suggested that GATA2 binding creates accessible chromatin regions enriched for both GATA and Retinoic Acid Receptor Element motifs, where GATA2 and PML::RARA can potentially bind and interact with each other. In turn, PML::RARA binding to DNA promotes a feed-forward transcriptional program by positively regulating Gata2 expression. Gata2 may therefore be required for PML::RARA to establish its transcriptional program.


Assuntos
Fator de Transcrição GATA2 , Células-Tronco Hematopoéticas , Proteínas de Fusão Oncogênica , Animais , Humanos , Camundongos , Sítios de Ligação , Autorrenovação Celular , Cromatina/metabolismo , DNA/metabolismo , Fator de Transcrição GATA2/metabolismo , Fator de Transcrição GATA2/genética , Células-Tronco Hematopoéticas/metabolismo , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/patologia , Proteínas de Fusão Oncogênica/metabolismo , Proteínas de Fusão Oncogênica/genética , Proteína da Leucemia Promielocítica/metabolismo , Proteína da Leucemia Promielocítica/genética , Ligação Proteica , Receptor alfa de Ácido Retinoico/metabolismo , Receptor alfa de Ácido Retinoico/genética
14.
Gut Pathog ; 16(1): 13, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38468325

RESUMO

BACKGROUND: The gut microbiota is associated with risk for colorectal cancer (CRC), a chronic disease for which racial disparities persist with Black Americans having a higher risk of CRC incidence and mortality compared to other groups. Given documented racial differences, the gut microbiota may offer some insight into previously unexplained racial disparities in CRC incidence and mortality. A case-control analysis comparing 11 women newly diagnosed with CRC with 22 cancer-free women matched on age, BMI, and race in a 1:2 ratio was conducted. Information about participants' diet and perceived stress levels were obtained via 24-h Dietary Recall and Perceived Stress Scale-10 survey, respectively. Participants provided stool samples from which microbial genomic DNA was extracted to reveal the abundance of 26 genera chosen a priori based on their previously observed relevance to CRC, anxiety symptoms, and diet. RESULTS: Significantly lower alpha diversity was observed among cancer-free Black women compared to all other race-cancer status combinations. No group differences were observed when comparing beta diversity. Non-Hispanic White CRC cases tended to have higher relative abundance of Fusobacteria, Gemellaceae, and Peptostreptococcus compared to all other race-cancer combination groups. Perceived stress was inversely associated with alpha diversity and was associated with additional genera. CONCLUSIONS: Our findings suggest that microbiome-CRC associations may differ by racial group. Additional large, racially diverse population-based studies are needed to determine if previously identified associations between characteristics of the gut microbiome and CRC are generalizable to Black women and other racial, ethnic, and gender groups.

15.
J Dairy Sci ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38460871

RESUMO

Variation in feed components contributes to variation and uncertainty of diets delivered to dairy cows. Forages often have a high inclusion rate (50 to 70% of DM fed) and variable composition, thus are an important contributor to nutrient variability of delivered diets. Our objective was to quantify the variation and identify the main sources of variability in corn silage and alfalfa-grass haylage composition at harvest (fresh forage) and feed-out (fermented forage) on NY dairy farms. Corn silage and alfalfa-grass haylage were sampled on 8 NY commercial dairy farms during harvest in the summer and fall of 2020 and during their subsequent feed-out in the winter and spring of 2021. At harvest, a composite sample of fresh chopped forage of every 8-ha section of individual fields was collected from piles delivered for silo filling. During a 16-week feed-out period, 2 independent samples of each forage were collected 3 times per week. The fields-of-origin of each forage sample during feed-out were identified and recorded using silo maps created at filling. A mixed-model analysis quantified the variance of corn silage DM, NDF, and starch and haylage DM, NDF, and CP content. Fixed effects included soil type, weather conditions, and management practices during harvest and feed-out while random effects were farm, silo unit, field, and day. At harvest, between-farm variability was the largest source of variation for both corn silage and haylage, but within-farm sources of variation exceeded farm-to-farm variation for haylage at feed-out. At feed-out, haylage DM and NDF content had higher within-farm variability than corn silage. In contrast, corn silage starch showed higher within-farm variation at feed-out than haylage CP content. For DM content at feed-out, day-to-day variation was the most relevant source of within-farm variation for both forages. However, for the nutrient components at feed-out (NDF and CP for haylage; NDF and starch for corn silage) silo-to-silo variation was the largest source of variability. Weather conditions systematically explained a proportion of the farm-to-farm variability for both forages at harvest and feed-out. We concluded that because of the high farm-to-farm variation, corn silage and haylage must be sampled on individual farms. We also concluded that due to the high silo-to-silo variability, and the still significant day-to-day and field-to-field variability within-farm, corn silage and haylage should be sampled within individual silos to better capture changes in forage components at feed-out.

16.
Phys Rev E ; 109(2-2): 025204, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38491565

RESUMO

In this work we present the design of the first controlled fusion laboratory experiment to reach target gain G>1 N221204 (5 December 2022) [Phys. Rev. Lett. 132, 065102 (2024)10.1103/PhysRevLett.132.065102], performed at the National Ignition Facility, where the fusion energy produced (3.15 MJ) exceeded the amount of laser energy required to drive the target (2.05 MJ). Following the demonstration of ignition according to the Lawson criterion N210808, experiments were impacted by nonideal experimental fielding conditions, such as increased (known) target defects that seeded hydrodynamic instabilities or unintentional low-mode asymmetries from nonuniformities in the target or laser delivery, which led to reduced fusion yields less than 1 MJ. This Letter details design changes, including using an extended higher-energy laser pulse to drive a thicker high-density carbon (also known as diamond) capsule, that led to increased fusion energy output compared to N210808 as well as improved robustness for achieving high fusion energies (greater than 1 MJ) in the presence of significant low-mode asymmetries. For this design, the burnup fraction of the deuterium and tritium (DT) fuel was increased (approximately 4% fuel burnup and a target gain of approximately 1.5 compared to approximately 2% fuel burnup and target gain approximately 0.7 for N210808) as a result of increased total (DT plus capsule) areal density at maximum compression compared to N210808. Radiation-hydrodynamic simulations of this design predicted achieving target gain greater than 1 and also the magnitude of increase in fusion energy produced compared to N210808. The plasma conditions and hotspot power balance (fusion power produced vs input power and power losses) using these simulations are presented. Since the drafting of this manuscript, the results of this paper have been replicated and exceeded (N230729) in this design, together with a higher-quality diamond capsule, setting a new record of approximately 3.88MJ of fusion energy and fusion energy target gain of approximately 1.9.

17.
Phys Rev E ; 109(2-2): 025203, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38491694

RESUMO

An indirect-drive inertial fusion experiment on the National Ignition Facility was driven using 2.05 MJ of laser light at a wavelength of 351 nm and produced 3.1±0.16 MJ of total fusion yield, producing a target gain G=1.5±0.1 exceeding unity for the first time in a laboratory experiment [Phys. Rev. E 109, 025204 (2024)10.1103/PhysRevE.109.025204]. Herein we describe the experimental evidence for the increased drive on the capsule using additional laser energy and control over known degradation mechanisms, which are critical to achieving high performance. Improved fuel compression relative to previous megajoule-yield experiments is observed. Novel signatures of the ignition and burn propagation to high yield can now be studied in the laboratory for the first time.

18.
J Evid Based Dent Pract ; 24(1S): 101950, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38401947

RESUMO

Oral health impact or oral health related quality of life is an increasingly important and well-known metric in dental care and research. There have been recent calls for greater integration of the behavioral and social sciences into oral health research and practice, including the need for frameworks and theories to guide this work. One such framework for understanding the role of predisposing, precipitating, and perpetuating biopsychosocial mechanisms in health and disease is the "3P" model. Here, the 3P model is described and applied to case examples to help understand the development and maintenance of oral health impact. Additionally, this paper outlines how this conceptualization using the 3P model and oral health impact makes way for greater integration of behavioral interventions to prevent, mitigate, or treat the negative impact that oral, craniofacial, or dental disease may have on individuals. Doing this allows for a broadening of what evidence-based dentistry means for the future and provides a roadmap going forward.


Assuntos
Odontologia Baseada em Evidências , Saúde Bucal , Humanos , Qualidade de Vida , Ciências Sociais
19.
J Environ Manage ; 354: 120270, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38377748

RESUMO

Solutions-driven research is a transdisciplinary approach that incorporates diverse forms of expertise to identify solutions to stakeholder-identified environmental problems. This qualitative evaluation of early solutions-driven research projects provides transferable recommendations to improve researcher and stakeholder experiences and outcomes in transdisciplinary environmental research projects. Researchers with the U.S. Environmental Protection Agency (EPA) Office of Research and Development recently piloted a solutions-driven research approach in two parallel projects; one addressing nutrient management related to coastal waters and another studying wildland fire smoke impacts on indoor air quality. Studying the experiences of those involved with these pilots can enhance the integration of researcher and experiential expertise, improving solutions-driven research outcomes. Data collection included semi-structured interviews with 17 EPA researchers and 12 other stakeholders and reflective case narratives from the authors. We used conventional content analysis to qualitatively analyze perspectives on implementing innovative engagement and research approaches in a solutions-driven process. Findings that reflect common perspectives include the importance of continuous engagement, the challenges of differing timelines and priorities for researchers and stakeholders, and the need to define consistent markers of success across researchers and stakeholders. Key lessons to improve transdisciplinary research identified from the analysis are (1) improving clarity of roles and responsibilities; (2) planning to provide sufficient, continuous project funding over multiple years; (3) expecting research needs and plans to adapt to evolving circumstances; and (4) clearly defining the end of the project.


Assuntos
Nutrientes , Saúde Pública
20.
Curr Dev Nutr ; 8(2): 102077, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38357379

RESUMO

Background: Bacterial-sourced single-cell proteins (SCPs) offer an alternative protein source for diet formulation for Zebrafish (Danio rerio) and other aquaculture models. In addition, the use of a single-cell bacterial protein source derived from multiple species provides a unique insight into the interplay among nutrients in the diet, microbial populations in the diet, and the gut microbiome in D. rerio. Objective: Our objective in this study was to evaluate the impact of dietary replacement of fish protein hydrolysate in a standard reference (SR) with a single-cell bacterial protein source on D. rerio gut microbiome. Methods: We investigated gut microbial compositions of D. rerio fed an open-formulation standard reference (SR) diet or a bacterial-sourced protein (BP) diet, utilizing microbial taxonomic co-occurrence networks, and predicted functional profiles. Results: Microbial communities in the SR diet were primarily composed of Firmicutes. In contrast, the BP diet was mainly composed of Proteobacteria. Alpha diversity revealed significant differences in microbial communities between the 2 diets, and between the guts of D. rerio fed either of the 2 diets. D. rerio fed with the SR diet resulted in abundance of Aeromonas and Vibrio. In contrast, D. rerio fed with a BP diet displayed a large abundance of members from the Rhodobacteraceae family. Taxonomic co-occurrence networks display unique microbial interactions, and key taxons in D. rerio gut samples were dependent on diet and gender. Predicted functional profiling of the microbiome across D. rerio fed SR or BP diets revealed distinct metabolic pathway differences. Female D. rerio fed the BP diet displayed significant upregulation of pathways related to primary and secondary bile acid synthesis. Male D. rerio fed the BP diet revealed similar pathway shifts and, additionally, a significant upregulation of the polyketide sugar unit biosynthesis pathway. Conclusions: The use of a BP dramatically affects the composition and activity of the gut microbiome. Future investigations should further address the interplay among biological systems and diet and may offer insights into potential health benefits in preclinical and translational animal models.

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