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Anion femtosecond photoelectron spectroscopy was used to follow the dynamics of the [I.sup.-[.sub.2]][(Ar).sub.6] and [I.sup.-[.sub.2]][(Ar).sub.20] clusters subsequent to photodissociation of the [I.sup.-₂] chromophore]. The experiments showed that photodissociation of the [I.sup.-[.sub.2]] moiety in [I.sup.-[.sub.2]][(Ar).sub.6], is complete by approximately 200 femtoseconds, just as in bare [I.sup.-[.sub.2]] but also that attractive interactions between the departing anion fragment and the solvent atoms persisted for 1200 femtoseconds. Photodissociation of [I.sup.-[.sub.2.[(Ar).sub.20] results in caging of the [I.sup.-[.sub.2]] followed by recombination and vibrational relaxation on the excited A [.sup.2[Π.sub.g,3/2]] and the ground [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] states; these processes are complete in 35 and 200 picoseconds, respectively., Understanding of the potential energy surfaces governing the dynamics of elementary chemical reactions in the gas phase has grown significantly during the past 10 years, largely because of the development [...]

Studies the femtosecond photoelectron spectroscopy of iodine clusters. Determination of the initial solvent configuration from measuring the number of solvent atoms around iodine; Measurement of the time-resolved number of solvent atoms; Vibrational relaxation in caged photofragments.

Studies the photodissociation dynamics of gas phase I[sup -][sub 3] after an excitation using femtosecond photoelectron spectroscopy. Coherent oscillations that correspond to vibrational excitation; Photoelectron spectrum induced by resonance impulsive stimulated Raman scattering.

Examines the solvation effects on vibrational frequency of I[sub 2]-chromophore in size-selected I[sub 2]-(AR)[sub n] and I[sub 2]-(CO[sub 2])[sub n] clusters. Stimulation of Raman scattering process to determine frequency; Detection of wave-packet oscillations with femtosecond photoelectron spectroscopy; Effect of solvation on frequency.

Studies a semiclassical method for stimulating femtosecond pump-probe photoelectron spectroscopy and its implementation to examine excited state photodissociation dynamics of iodine anion. Initial value representation method for calculating the time dependent photodetachment spectrum as a function of kinetic energy; Radiation-chromophore interaction.

Describes the characterization of the I[sup -][sub 2] anion ground state with the use of conventional and femtosecond photoelectron spectroscopy. Conventional photoelectron spectrum; Femtosecond photoelectron spectroscopy; Origin and significance of the coherences.

The photodissociation dynamics of I[sub 2][sup -](CO[sub 2])[sub n](n=4-16) clusters excited at 780 nm have been studied with femtosecond photoelectron spectroscopy (FPES). The range of cluster sizes spans the uncaged and fully-caged product limits for this reaction. We observe time scales for a variety of processes in these clusters, including dissociation of the I[sub 2][sup -] chromophore, solvation of the I[sup -] fragment, the onset of recombination on the ground state of I[sub 2][sup -], vibrational relaxation, and solvent evaporation. In addition, substantial trapping in a "solvent-separated" state is seen for clusters with n>=9; this state persists for at least 200 ps, the longest time delay probed here. Simulations of the spectra were performed in order to determine the time dependence of the electronic state populations, the I[sub 2][sup -] vibrational distribution, and the number of CO[sub 2] molecules in the cluster. Results are compared to previous experimental and theoretical studies of I[sub 2][sup -](CO[sub 2])[sub n] photodissociation, and to a recent FPES study of I[sub 2][sup -](Ar)[sub n] clusters. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

BACKGROUNDCOVID-19 convalescent plasma (CCP) virus-specific antibody levels that translate into recipient posttransfusion antibody levels sufficient to prevent disease progression are not defined.METHODSThis secondary analysis correlated donor and recipient antibody levels to hospitalization risk among unvaccinated, seronegative CCP recipients within the outpatient, double-blind, randomized clinical trial that compared CCP to control plasma. The majority of COVID-19 CCP arm hospitalizations (15/17, 88%) occurred in this unvaccinated, seronegative subgroup. A functional cutoff to delineate recipient high versus low posttransfusion antibody levels was established by 2 methods: (i) analyzing virus neutralization-equivalent anti-Spike receptor-binding domain immunoglobulin G (anti-S-RBD IgG) responses in donors or (ii) receiver operating characteristic (ROC) curve analysis.RESULTSSARS-CoV-2 anti-S-RBD IgG antibody was volume diluted 21.3-fold into posttransfusion seronegative recipients from matched donor units. Virus-specific antibody delivered was approximately 1.2 mg. The high-antibody recipients transfused early (symptom onset within 5 days) had no hospitalizations. A CCP-recipient analysis for antibody thresholds correlated to reduced hospitalizations found a statistical significant association between early transfusion and high antibodies versus all other CCP recipients (or control plasma), with antibody cutoffs established by both methods-donor-based virus neutralization cutoffs in posttransfusion recipients (0/85 [0%] versus 15/276 [5.6%]; P = 0.03) or ROC-based cutoff (0/94 [0%] versus 15/267 [5.4%]; P = 0.01).CONCLUSIONIn unvaccinated, seronegative CCP recipients, early transfusion of plasma units in the upper 30% of study donors' antibody levels reduced outpatient hospitalizations. High antibody level plasma units, given early, should be reserved for therapeutic use.TRIAL REGISTRATIONClinicalTrials.gov NCT04373460.FUNDINGDepartment of Defense (W911QY2090012); Defense Health Agency; Bloomberg Philanthropies; the State of Maryland; NIH (3R01AI152078-01S1, U24TR001609-S3, 1K23HL151826NIH); the Mental Wellness Foundation; the Moriah Fund; Octapharma; the Healthnetwork Foundation; the Shear Family Foundation; the NorthShore Research Institute; and the Rice Foundation.

Importance: This study examined the role that cytokines may have played in the beneficial outcomes found when outpatient individuals infected with SARS-CoV-2 were transfused with COVID-19 convalescent plasma (CCP) early in their infection. We found that the pro-inflammatory cytokine IL-6 decreased significantly faster in patients treated early with CCP. Participants with COVID-19 treated with CCP later in the infection did not have the same effect. This decrease in IL-6 levels after early CCP treatment suggests a possible role of inflammation in COVID-19 progression. The evidence of IL-6 involvement brings insight into the possible mechanisms involved in CCP treatment mitigating SARS-CoV-2 severity.

Background: COVID-19 convalescent plasma (CCP) is an important therapeutic option for outpatients at high risk of hospitalization from SARS-CoV-2 infection. We assessed the safety of outpatient CCP transfusions administered during clinical trials., Study Design and Methods: We analyzed data pertaining to transfusion-related reactions from two randomized controlled trials in the U.S. that evaluated the efficacy of CCP versus control plasma in various ambulatory settings. Multivariable logistic regression was used to assess whether CCP was associated with transfusion reactions, after adjusting for potential confounders., Results: The combined study reported 79/1351 (5.9%) adverse events during the transfusion visit, with the majority 62/1351 (4.6%) characterized by mild, allergic-type findings of urticaria, and/or pruritus consistent with minor allergic transfusion reactions; the other reported events were attributed to the patients' underlying disease, COVID-19, or vasovagal in nature. We found no difference in the likelihood of allergic transfusion reactions between those receiving CCP versus control plasma (adjusted odds ratio [AOR], 0.75; 95% CI, 0.43-1.31). Risk of urticaria and/or pruritus increased with a pre-existing diagnosis of asthma (AOR, 2.33; 95% CI, 1.16-4.67). We did not observe any CCP-attributed antibody disease enhancement in participants with COVID-19 or increased risk of infection. There were no life-threatening severe transfusion reactions and no patients required hospitalization related to transfusion-associated complications., Discussion: Outpatient plasma administration was safely performed for nearly 1400 participants. CCP is a safe therapeutic option for outpatients at risk of hospitalization from COVID-19., (© 2023 The Authors. Transfusion published by Wiley Periodicals LLC on behalf of AABB.)

Background: Cytokines and chemokines play a critical role in the response to infection and vaccination. We aimed to assess the longitudinal association of COVID-19 vaccination with cytokine and chemokine concentrations and trajectories among people with SARS-CoV-2 infection., Methods: In this longitudinal, prospective cohort study, blood samples were used from participants enrolled in a multi-centre randomised trial assessing the efficacy of convalescent plasma therapy for ambulatory COVID-19. The trial was conducted in 23 outpatient sites in the USA. In this study, participants (aged ≥18 years) were restricted to those with COVID-19 before vaccination or with breakthrough infections who had blood samples and symptom data collected at screening (pre-transfusion), day 14, and day 90 visits. Associations between COVID-19 vaccination status and concentrations of 21 cytokines and chemokines (measured using multiplexed sandwich immunoassays) were examined using multivariate linear mixed-effects regression models, adjusted for age, sex, BMI, hypertension, diabetes, trial group, and COVID-19 waves (pre-alpha or alpha and delta)., Findings: Between June 29, 2020, and Sept 30, 2021, 882 participants recently infected with SARS-CoV-2 were enrolled, of whom 506 (57%) were female and 376 (43%) were male. 688 (78%) of 882 participants were unvaccinated, 55 (6%) were partly vaccinated, and 139 (16%) were fully vaccinated at baseline. After adjusting for confounders, geometric mean concentrations of interleukin (IL)-2RA, IL-7, IL-8, IL-15, IL-29 (interferon-λ), inducible protein-10, monocyte chemoattractant protein-1, and tumour necrosis factor-α were significantly lower among the fully vaccinated group than in the unvaccinated group at screening. On day 90, fully vaccinated participants had approximately 20% lower geometric mean concentrations of IL-7, IL-8, and vascular endothelial growth factor-A than unvaccinated participants. Cytokine and chemokine concentrations decreased over time in the fully and partly vaccinated groups and unvaccinated group. Log 10 cytokine and chemokine concentrations decreased faster among participants in the unvaccinated group than in other groups, but their geometric mean concentrations were generally higher than fully vaccinated participants at 90 days. Days since full vaccination and type of vaccine received were not correlated with cytokine and chemokine concentrations., Interpretation: Initially and during recovery from symptomatic COVID-19, fully vaccinated participants had lower concentrations of inflammatory markers than unvaccinated participants suggesting vaccination is associated with short-term and long-term reduction in inflammation, which could in part explain the reduced disease severity and mortality in vaccinated individuals., Funding: US Department of Defense, National Institutes of Health, Bloomberg Philanthropies, State of Maryland, Mental Wellness Foundation, Moriah Fund, Octapharma, HealthNetwork Foundation, and the Shear Family Foundation., Competing Interests: Declaration of interests KAG reports consultancy work for the Aspen Institute, Teach for America, serving as a non-paid member of a scientific advisory board for Pfizer, and writing COVID-19 management guidelines for UpToDate. AGA reports consultancy work for Implementation Group, Hirslanden Klinik, and Elsevier. ERC reports receiving unrestricted research grants from Gilead and Merck paid to the Regents of the University of California and participating in an advisory board to Theratechnologies for an unrelated topic. JSC reports consultancy work for Merck and Company in 2021. TJG reports employment by Fenwal, a Fresenius Kabi Company. LLH reports research funding to Johns Hopkins Center of American Indian Health from AstraZeneca, US Centers for Disease Control and Prevention, Merck, NIH, and Pfizer. MAH reports contracts from Gilead Sciences, Insmed, and AN2 Therapeutics to the University of Cincinnati. GSM reports research grant support from Teva, Alk-Abello, Genentech, Novartis, GlaxoSmithKline, and Sanofi-Regeneron, serving as an immediate past president of the American Academy of Allergy Asthma and Immunology, and is co-chair of the Continuous Assessment Program Examination for the American Board of Allergy and Immunology. BP reports participating in part of the COVID-19 trials and pulmonary arterial hypertension trials. JHP reports research funding from MindRhythm. JSR is a consultant and advisor with Sanofi Genzyme, and a board of directors member with the American Society for Apheresis. SK reports helping to produce educational materials related to HIV with Integritas Communications and Vindico Medical Education. AC reports serving on the scientific advisory board of SAB Biotherapeutics. EMB reports personal fees and non-financial support from Terumo BCT, Abbott Laboratories, Tegus, and UptoDate, is a member of the US Food and Drug Administration Blood Products Advisory Committee, and served on a convalescent plasma guideline panel. DH reports personal fees from Neurelis, Neurotrope, and medicolegal consulting. DJS is a founder and board member with stock options (macrolide for malaria) for AliquantumRx and reports consulting for Hemex Health and royalties for malaria diagnostic test control standards to Alere. SLH reports serving on the data monitoring committee for Pfizer. All other authors declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: Polyclonal convalescent plasma may be obtained from donors who have recovered from coronavirus disease 2019 (Covid-19). The efficacy of this plasma in preventing serious complications in outpatients with recent-onset Covid-19 is uncertain., Methods: In this multicenter, double-blind, randomized, controlled trial, we evaluated the efficacy and safety of Covid-19 convalescent plasma, as compared with control plasma, in symptomatic adults (≥18 years of age) who had tested positive for severe acute respiratory syndrome coronavirus 2, regardless of their risk factors for disease progression or vaccination status. Participants were enrolled within 8 days after symptom onset and received a transfusion within 1 day after randomization. The primary outcome was Covid-19-related hospitalization within 28 days after transfusion., Results: Participants were enrolled from June 3, 2020, through October 1, 2021. A total of 1225 participants underwent randomization, and 1181 received a transfusion. In the prespecified modified intention-to-treat analysis that included only participants who received a transfusion, the primary outcome occurred in 17 of 592 participants (2.9%) who received convalescent plasma and 37 of 589 participants (6.3%) who received control plasma (absolute risk reduction, 3.4 percentage points; 95% confidence interval, 1.0 to 5.8; P = 0.005), which corresponded to a relative risk reduction of 54%. Evidence of efficacy in vaccinated participants cannot be inferred from these data because 53 of the 54 participants with Covid-19 who were hospitalized were unvaccinated and 1 participant was partially vaccinated. A total of 16 grade 3 or 4 adverse events (7 in the convalescent-plasma group and 9 in the control-plasma group) occurred in participants who were not hospitalized., Conclusions: In participants with Covid-19, most of whom were unvaccinated, the administration of convalescent plasma within 9 days after the onset of symptoms reduced the risk of disease progression leading to hospitalization. (Funded by the Department of Defense and others; CSSC-004 ClinicalTrials.gov number, NCT04373460.)., (Copyright © 2022 Massachusetts Medical Society.)

Background: The proposed 2015 US Preventive Services Task Force guidelines recommend diabetes screening for individuals ≥45 years or demonstrating other risk factors for dysglycemia. Still, many patients with dysglycemia remain undiagnosed, and opportunities for early intervention are lost., Methods: To test novel approaches for diagnosis using the haemoglobin A1c (HbA1c ) test, we screened adult patients who were admitted to an observation unit from the emergency department with no known history of pre-diabetes or diabetes., Results: Of 256 subjects, 9% were newly diagnosed with diabetes and 52% were newly diagnosed with pre-diabetes. Of those aged 18-29 years, 33% were newly diagnosed with dysglycemia, while 55% of those aged 30-44 years and 70% of those aged ≥45 years were newly diagnosed with dysglycemia., Conclusions: Our results suggest that regardless of age, a large proportion of patients in the emergency department observation unit have undiagnosed dysglycemia, an important finding given the large number of observation admissions. Copyright © 2015 John Wiley & Sons, Ltd., (Copyright © 2015 John Wiley & Sons, Ltd.)

The current political-economic climate, which is generally supportive of both private and public sector down-sizing, increasingly demands that human service workers assess, engage, and creatively use consumer strengths and resources. This meta-analysis of thirty-seven independent studies provided the means of inferring not only that elder volunteers' sense of well-being seemed to be significantly bolstered through volunteering, but also that such relatively healthy older people represent a significant adjunct resource for meeting some of the service needs of more vulnerable elders, as well as those of other similarly vulnerable groups such as disabled children. Averaging across studies, 85 percent of the "clients" who received service from an older volunteer (e.g., peer-counseling of nursing home residents) scored better on dependent measures (e.g., diminished depression) than the average person in comparison conditions did (U3 = .847 [Cohen, 1988], combined p < .001). The policy implications of such beneficial effects among both older volunteers and the people they serve are discussed.