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1.
Gerontol Geriatr Educ ; 43(2): 269-284, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-30442079

RESUMEN

Palliative care has demonstrated effectiveness in alleviating the biological, emotional, social, and spiritual symptoms that accompany serious illness, and improving quality of life for seriously ill individuals and their family members. Despite increasing availability, there are significant disparities in access to and utilization of palliative care, particularly among diverse, low-income, and community-dwelling older adults with chronic illness. Training frontline service providers is a novel approach to expanding access to palliative care among underserved elders. This article presents a process and outcome evaluation of a palliative care curriculum that was developed and piloted for geriatric case managers in a large urban area. We describe the background, planning, design, implementation, and preliminary outcomes associated with a pilot implementation of the curriculum. We conclude with implications for replicating efforts to enhance frontline providers' knowledge, skills, and self-efficacy in extending palliative care to communities that lack access to critical supports for their burdensome symptoms.


Asunto(s)
Gestores de Casos , Geriatría , Anciano , Creación de Capacidad , Geriatría/educación , Humanos , Cuidados Paliativos , Calidad de Vida
2.
Support Care Cancer ; 29(10): 5753-5762, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33738592

RESUMEN

PURPOSE: Coping behaviors may play a mediating role in producing the negative health outcomes observed in financially burdened cancer patients and survivors. METHODS: Exploratory factor and latent class analysis of survey data. RESULTS: A total of 510 people completed the survey, ages ranged from 25 to over 75 [over half greater than 55 years old (57.8%)]. Most respondents identified as female (64.7%), white (70.8%), or African American (18.6%). A four-factor model of financial coping was revealed: care-altering, lifestyle-altering, self-advocacy, and financial help-seeking. Respondents grouped into three financial coping classes: low burden/low coping (n = 212), high self-advocacy (n = 143), and high burden/high coping (n = 155). African American respondents were at far greater odds than white respondents of being in the high burden/high coping class (OR = 5.82, 95% CI 3.01-6.64) or the self-advocacy class (OR = 1.99, 95% CI 1.19-2.80) than the low burden/low coping class. Compared to respondents aged 65 years and older, those 35-44 were more likely in the high burden/high coping class (OR = 12.27, 95% CI 7.03-19.87) and the high self-advocacy class (OR = 7.08, 95% CI 5.89-8.28) than the low burden/low coping class. CONCLUSION: One-third of respondents were in the high burden/high coping class. Age and race/ethnicity were significantly associated with class membership. Some coping strategies may compromise health and well-being. Program and policy interventions that reduce the odds that patients will use strategies that undermine treatment outcomes and increase patient use of protective strategies are needed.


Asunto(s)
Adaptación Psicológica , Neoplasias , Adulto , Femenino , Humanos , Estilo de Vida , Encuestas y Cuestionarios , Sobrevivientes
3.
Ann Plast Surg ; 86(3S Suppl 2): S336-S341, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33234885

RESUMEN

ABSTRACT: Soft tissue sarcomas are a heterogenous group of malignant tumors that represent approximately 1% of adult malignancies. Although these tumors occur throughout the body, the majority involved the lower extremity. Management may involve amputation but more commonly often includes wide local resection by an oncologic surgeon and involvement of a plastic surgeon for reconstruction of larger and more complex defects. Postoperative wound complications are challenging for the surgeon and patient but also impact management of adjuvant chemotherapy and radiation therapy. To explore risk factors for wound complications, we reviewed our single-institution experience of lower-extremity soft tissue sarcomas from April 2009 to September 2016. We identified 127 patients for retrospective review and analysis. The proportion of patients with wound complications in the cohort was 43.3%. Most notably, compared with patients without wound complications, patients with wound complications had a higher proportion of immediate reconstruction (34.5% vs 15.3%; P = 0.05) and a marginally higher proportion who received neoadjuvant radiation (30.9% vs 16.7%; P = 0.06).


Asunto(s)
Sarcoma , Neoplasias de los Tejidos Blandos , Adulto , Humanos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Radioterapia Adyuvante/efectos adversos , Estudios Retrospectivos , Factores de Riesgo , Sarcoma/cirugía , Neoplasias de los Tejidos Blandos/cirugía , Cicatrización de Heridas
4.
J Psychosoc Oncol ; 37(4): 441-455, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30451102

RESUMEN

PURPOSE: To explore the psychosocial needs of cancer patients and survivors across the United States and their implications for value-based oncology. DESIGN: A secondary analysis of findings from a cross-sectional national online survey. SAMPLE: Respondents were sampled and stratified by cancer type and geographic region to approximate the cancer-affected population of the United States. Breast, prostate, and colorectal were the most common cancers reported. Across surveys, the majority of respondents were female (57%), over 55 (60%), and white (70%) and had at least some college (36%). METHODS: Six online surveys were administered to cohorts of approximately 500 unique cancer patients and survivors. Survey topics included: (1) diagnosis, (2) treatment planning, (3) communication with providers, (4) insurance and financial concerns, (5) quality of life, side effects, and symptoms, and (6) survivorship and end-of-life. Descriptive analyses were used to explore psychosocial needs and experiences across three domains of patient-centered value in oncology. FINDINGS: Each survey received 500-527 responses. Respondents most commonly reported needing more information regarding their insurance coverage and out-of-pocket costs (65%), access to clinical trials (89%), and support organizations (45%). Forty-one percent were very or extremely distressed about cancer's impact on their ability to work and over 25% reported high-levels of cancer-related financial hardship. CONCLUSIONS: Patients and survivors reported significant unmet informational needs, financial hardship, distress, and symptoms or treatment side effects that interfered with daily life. Implications for Psychosocial Providers or Policy: Providers and payment reform advocates can improve value in oncology by ensuring access to comprehensive psychosocial care and informational support.


Asunto(s)
Supervivientes de Cáncer/psicología , Necesidades y Demandas de Servicios de Salud , Oncología Médica/economía , Neoplasias/psicología , Sistemas de Apoyo Psicosocial , Adulto , Anciano , Supervivientes de Cáncer/estadística & datos numéricos , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/terapia , Encuestas y Cuestionarios , Estados Unidos
7.
J Biol Chem ; 290(45): 27204-27214, 2015 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-26381408

RESUMEN

Ferrous myoglobin was oxidized by sulfur trioxide anion radical (STAR) during the free radical chain oxidation of sulfite. Oxidation was inhibited by the STAR scavenger GSH and by the heme ligand CO. Bimolecular rate constants for the reaction of STAR with several ferrous globins and biomolecules were determined by kinetic competition. Reaction rate constants for myoglobin, hemoglobin, neuroglobin, and flavohemoglobin are large at 38, 120, 2,600, and ≥ 7,500 × 10(6) m(-1) s(-1), respectively, and correlate with redox potentials. Measured rate constants for O2, GSH, ascorbate, and NAD(P)H are also large at ∼100, 10, 130, and 30 × 10(6) m(-1) s(-1), respectively, but nevertheless allow for favorable competition by globins and a capacity for STAR scavenging in vivo. Saccharomyces cerevisiae lacking sulfite oxidase and deleted of flavohemoglobin showed an O2-dependent growth impairment with nonfermentable substrates that was exacerbated by sulfide, a precursor to mitochondrial sulfite formation. Higher O2 exposures inactivated the superoxide-sensitive mitochondrial aconitase in cells, and hypoxia elicited both aconitase and NADP(+)-isocitrate dehydrogenase activity losses. Roles for STAR-derived peroxysulfate radical, superoxide radical, and sulfo-NAD(P) in the mechanism of STAR toxicity and flavohemoglobin protection in yeast are suggested.


Asunto(s)
Globinas/metabolismo , Óxidos de Azufre/metabolismo , Aconitato Hidratasa/metabolismo , Animales , Dioxigenasas/genética , Dioxigenasas/metabolismo , Mononucleótido de Flavina/metabolismo , Depuradores de Radicales Libres/metabolismo , Radicales Libres/metabolismo , Glutatión/metabolismo , Hemoproteínas/genética , Hemoproteínas/metabolismo , Isocitrato Deshidrogenasa/metabolismo , Cinética , Oxidación-Reducción , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Sulfitos/metabolismo , Superóxido Dismutasa/metabolismo
8.
J Am Chem Soc ; 137(11): 3981-90, 2015 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-25737076

RESUMEN

We have prepared a G-quadruplex (GQ-1) that incorporates an 8-(4'-aminophenylethynyl)guanine (GEAn) electron donor covalently attached to a 4-aminonaphthalene-1,8-imide (ANI) chromophore and a naphthalene-1,8:4,5-bis(dicarboximide) (NDI) electron acceptor (GEAn-ANI-NDI, 1). In the presence of KPF6 in tetrahydrofuran (THF), 1 self-assembles into a monodisperse, C4-symmetric GQ-1 with small spatial intraquadruplex overlap between the ANI-NDI units. Photoexcitation of monomeric 1 induces the two-step charge transfer GEAn-(1)*ANI-NDI → GEAn(+•)-ANI(-•)-NDI → GEAn(+•)-ANI-NDI(-•) that occurs in τ(CS1) = 5 ps and τ(CS2) = 330 ps, respectively, while charge recombination in ca. 300 ns. Sharpening of the GEAn(+•) transient absorption and a shift of the ethynyl vibrational frequency in 1 were observed, concomitant with the stepwise electron transfer from ANI(-•) to NDI. Formation of GQ-1 from 1 in THF increases the secondary charge-shifting rate (τ(CS2) = 110 ps) and results in no change in ethynyl vibrational frequency. Charge recombination in GQ-1 is slowed by enhanced radical-pair intersystem crossing driven by the greater number of hyperfine couplings in the assembly. Moreover, time-resolved EPR spectroscopy shows that the spin-spin-exchange interaction (J) between the radicals of GEAn(+•)-ANI-NDI(-•) within GQ-1 is smaller than that of 1, suggesting that the spin (charge) density in GEAn(+•) is more dispersed in GQ-1. The spectroscopic results are consistent with hole sharing among the guanines within the G-quadruplex that is kinetically competitive with the formation of GEAn(+•). This suggests that G-quadruplexes can serve as effective hole conduits in ordered donor-acceptor assemblies.


Asunto(s)
G-Cuádruplex , Luz , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Conformación de Ácido Nucleico
9.
J Am Chem Soc ; 137(41): 13236-9, 2015 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-26418462

RESUMEN

We report on a visible-light-absorbing chiral molecular triangle composed of three covalently linked 1,6,7,12-tetra(phenoxy)perylene-3,4:9,10-bis(dicarboximide) (PDI) units. The rigid triangular architecture reduces the electronic coupling between the PDIs, so ultrafast symmetry-breaking charge separation is kinetically favored over intramolecular excimer formation, as revealed by femtosecond transient absorption spectroscopy. Photoexcitation of the PDI triangle dissolved in CH2Cl2 gives PDI(+•)-PDI(-•) in τCS = 12.0 ± 0.2 ps. Fast subsequent intramolecular electron/hole hopping can equilibrate the six possible energetically degenerate ion-pair states, as suggested by electron paramagnetic resonance/electron-nuclear double resonance spectroscopy, which shows that one-electron reduction of the PDI triangle results in complete electron sharing among the three PDIs. Charge recombination of PDI(+•)-PDI(-•) to the ground state occurs in τCR = 1.12 ± 0.01 ns with no evidence of triplet excited state formation.


Asunto(s)
Imidas/química , Perileno/análogos & derivados , Electrones , Perileno/química , Procesos Fotoquímicos , Espectroscopía de Protones por Resonancia Magnética , Espectrometría de Fluorescencia , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrofotometría Ultravioleta
10.
J Am Chem Soc ; 137(2): 857-63, 2015 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-25478639

RESUMEN

Understanding the fundamental spin dynamics of photoexcited pentacene derivatives is important in order to maximize their potential for optoelectronic applications. Herein, we report on the synthesis of two pentacene derivatives that are functionalized with the [(2,2,6,6-tetramethylpiperidin-1-yl)oxy] (TEMPO) stable free radical. The presence of TEMPO does not quench the pentacene singlet excited state, but does quench the photoexcited triplet excited state as a function of TEMPO-to-pentacene distance. Time-resolved electron paramagnetic resonance experiments confirm that triplet quenching is accompanied by electron spin polarization transfer from the pentacene excited state to the TEMPO doublet state in the weak coupling regime.


Asunto(s)
Óxidos N-Cíclicos/química , Fenómenos Magnéticos , Naftacenos/química , Procesos Fotoquímicos , Espectroscopía de Resonancia por Spin del Electrón , Radicales Libres/química , Modelos Moleculares , Conformación Molecular , Naftacenos/síntesis química
11.
J Phys Chem A ; 119(29): 8040-8, 2015 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-26098409

RESUMEN

Transient electron paramagnetic resonance (TREPR) spectroscopy has been used to study the spin-spin interactions in a novel U-shaped electron donor-chromophore-acceptor-radical (D-C-A-R(•)) system in which a xanthene bridge holds a tert-butylphenyl nitroxide (BPNO(•)) radical in close proximity to a naphthalene-1,8:4,5-bis(dicarboximide) (NDI) acceptor. Photoexcitation of the 4-aminonaphthalene-1,8-dicarboximide (ANI) chromophore results in rapid, two-step electron transfer to generate the triradical (D(+•)-C-A(-•)-R(•)). The large through-bond distance between A(-•) and R(•) makes their spin-spin exchange interaction (2JAR) negligibly small, whereas their short through-space distance results in a strong dipolar interaction (DAR), which is observed as a set of broad lines in the TREPR spectra of D(+•)-C-A(-•)-R(•) in solid toluene solution at 85 K. Transient nutation experiments show that these transitions belong to a species with spin S = 1, whereas experiments on D(+•)-C-A(-•)-R(•) in the oriented nematic liquid crystal 4-cyano-4'-n-pentylbiphenyl at 85 K demonstrate the anisotropy of DAR.

12.
J Soc Work End Life Palliat Care ; 11(2): 107-31, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26380922

RESUMEN

As Americans live longer with chronic illnesses, there is a growing need for social workers with the knowledge and skills to deliver quality palliative care to older adults and their families. Nevertheless, there remains a critical shortage of social workers prepared to provide quality palliative and end-of-life care (PELC) and to maintain the field into the next generation. Formal mentorship programs represent an innovative approach to enhancing practice, providing support and guidance, and promoting social work leadership in the field. This article reviews the literature on mentorship as an approach to professional and leadership development for emerging social workers in PELC. The Zelda Foster Studies Program in Palliative and End-of-Life Care bolsters competencies and mentors social workers in PELC over the trajectory of their careers, and enhances the capacity in the field. Findings from the first six years of two components of the ZF Program are examined to illustrate the feasibility, benefits, and challenges of formal mentorship programs. The authors describe the background, structure, and evaluation of the initiative's mentorship programs, and discuss the implications of mentorship in PELC for social work education, practice, and research.


Asunto(s)
Mentores , Medicina Paliativa/educación , Trabajadores Sociales/educación , Cuidado Terminal/métodos , Becas , Humanos , Liderazgo , New York , Evaluación de Programas y Proyectos de Salud , Servicio Social/educación , Servicio Social/métodos
13.
Behav Sci Law ; 33(4): 390-406, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26294380

RESUMEN

The current study investigated the effects of misinformation on children's memory reports after practice with the logic-of-opposition instruction at time of test. Four- and 6-year-old children participated in a play event in Session 1. During a two-week delay, parents presented their children with either misinformation or correct information about the play event. Prior to a memory interview in Session 2, some misled children were given a developmentally appropriate logic-of-opposition instruction to not report information provided by their parents. Results indicated that children were misled by the incorrect information, but that the logic-of-opposition instruction aided in the children's retrieval of the original memory, particularly for the 6-year-olds. Implications of the results for memory malleability and social demand effects in children are discussed.


Asunto(s)
Conducta Infantil/psicología , Comunicación , Recuerdo Mental , Sugestión , Análisis de Varianza , Niño , Preescolar , Derecho Penal , Femenino , Humanos , Entrevistas como Asunto , Lógica , Masculino , Relaciones Padres-Hijo , Juego e Implementos de Juego
14.
Behav Sci Law ; 32(6): 829-45, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25430607

RESUMEN

This study investigated the influence of communicator (child victim) and perceiver (adult participant) characteristics on expectations about witnesses' emotional displays during testimony. In total, 191 adults were asked whether or not they expected child victims who were testifying about sexual abuse to display sadness, fear, anger, disgust, happiness, or a neutral demeanor, and how intensely the adults expected each emotion to be displayed. In describing the victims, child age (5 vs. 13 years old) and child gender (female vs. male) were factorially combined as within-subject factors. Results included that victim gender predicted expectations of fear, and victim age predicted expectations of anger and disgust. There was a significant interaction of victim age and victim gender for expectations of sadness. Of participants who expected multiple emotions, a combination of negative and neutral emotions was expected more from 13-year-old female victims than from 5-year-old female victims. Child victim empathy predicted ratings of how intensely sad and fearful the child victim would look. Implications of these findings for psychological research and the legal system are discussed.


Asunto(s)
Abuso Sexual Infantil , Víctimas de Crimen , Emociones , Empatía , Adolescente , Adulto , Factores de Edad , Ira , Preescolar , Miedo , Femenino , Felicidad , Humanos , Masculino , Percepción , Factores Sexuales , Adulto Joven
15.
Angew Chem Int Ed Engl ; 53(36): 9476-81, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-25044761

RESUMEN

Investigating through-space electronic communication between discrete cofacially oriented aromatic π-systems is fundamental to understanding assemblies as diverse as double-stranded DNA, organic photovoltaics and thin-film transistors. A detailed understanding of the electronic interactions involved rests on making the appropriate molecular compounds with rigid covalent scaffolds and π-π distances in the range of ca. 3.5 Å. Reported herein is an enantiomeric pair of doubly-bridged naphthalene-1,8:4,5-bis(dicarboximide) (NDI) cyclophanes and the characterization of four of their electronic states, namely 1) the ground state, 2) the exciton coupled singlet excited state, 3) the radical anion with strong through-space interactions between the redox-active NDI molecules, and 4) the diamagnetic diradical dianion using UV/Vis/NIR, EPR and ENDOR spectroscopies in addition to X-ray crystallography. Despite the unfavorable Coulombic repulsion, the singlet diradical dianion dimer of NDI shows a more pronounced intramolecular π-π stacking interaction when compared with its neutral analog.


Asunto(s)
Naftalenos/química , Dimerización , Electroquímica , Modelos Moleculares , Conformación Molecular , Oxidación-Reducción , Estereoisomerismo
16.
Angew Chem Int Ed Engl ; 53(17): 4442-9, 2014 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-24623608

RESUMEN

The controlled self-assembly of well-defined and spatially ordered π-systems has attracted considerable interest because of their potential applications in organic electronics. An important contemporary pursuit relates to the investigation of charge transport across noncovalently coupled components in a stepwise fashion. Dynamic oligorotaxanes, prepared by template-directed methods, provide a scaffold for directing the construction of monodisperse one-dimensional assemblies in which the functional units communicate electronically through-space by way of π-orbital interactions. Reported herein is a series of oligorotaxanes containing one, two, three and four naphthalene diimide (NDI) redox-active units, which have been shown by cyclic voltammetry, and by EPR and ENDOR spectroscopies, to share electrons across the NDI stacks. Thermally driven motions between the neighboring NDI units in the oligorotaxanes influence the passage of electrons through the NDI stacks in a manner reminiscent of the conformationally gated charge transfer observed in DNA.


Asunto(s)
Electrones , Imidas/química , Naftalenos/química , Rotaxanos/química , Catálisis , Espectroscopía de Resonancia por Spin del Electrón , Enlace de Hidrógeno , Modelos Moleculares , Conformación Molecular
17.
CBE Life Sci Educ ; 23(2): es2, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38442149

RESUMEN

There is widespread recognition that undergraduate students in the life sciences must learn how to work in teams. However, instructors who wish to incorporate teamwork into their classrooms rarely have formal training in how to teach teamwork. This is further complicated by the application of synonymous and often ambiguous terminology regarding teamwork that is found in literature spread among many different disciplines. There are significant barriers for instructors wishing to identify and implement best practices. We synthesize key concepts in teamwork by considering the knowledge, skills, and attitudes (KSAs) necessary for success, the pedagogies and curricula for teaching those KSAs, and the instruments available for evaluating and assessing success. There are only a limited number of studies on teamwork in higher education that present an intervention with a control group and a formal evaluation or assessment. Moreover, these studies are almost exclusively outside STEM disciplines, raising questions about their extensibility. We conclude by considering how to build an evidence base for instruction that will empower students with the KSAs necessary for participating in a lifetime of equitable and inclusive teamwork.


Asunto(s)
Disciplinas de las Ciencias Biológicas , Estudiantes , Humanos , Curriculum , Aprendizaje , Conocimiento
18.
Nat Rev Neurosci ; 9(7): 557-68, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18568015

RESUMEN

Neuroscience produces a vast amount of data from an enormous diversity of neurons. A neuronal classification system is essential to organize such data and the knowledge that is derived from them. Classification depends on the unequivocal identification of the features that distinguish one type of neuron from another. The problems inherent in this are particularly acute when studying cortical interneurons. To tackle this, we convened a representative group of researchers to agree on a set of terms to describe the anatomical, physiological and molecular features of GABAergic interneurons of the cerebral cortex. The resulting terminology might provide a stepping stone towards a future classification of these complex and heterogeneous cells. Consistent adoption will be important for the success of such an initiative, and we also encourage the active involvement of the broader scientific community in the dynamic evolution of this project.


Asunto(s)
Corteza Cerebral/citología , Interneuronas , Ácido gamma-Aminobutírico/metabolismo , Potenciales de Acción , Axones/ultraestructura , Corteza Cerebral/metabolismo , Humanos , Interneuronas/clasificación , Interneuronas/citología , Interneuronas/metabolismo , Sinapsis/ultraestructura
19.
Bioorg Med Chem Lett ; 23(13): 3833-40, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23707259

RESUMEN

A series of compounds which exhibited good human CCR1 binding and functional potency was modified resulting in the discovery of a novel series of high affinity, functionally potent antagonists of the CCR1 receptor. Issues of PXR activity, ion-channel potency, and poor metabolic stability were addressed by the addition of a hydroxyl group to an otherwise lipophilic area in the molecule resulting in the discovery of preclinical candidate BMS-457 for the treatment of rheumatoid arthritis.


Asunto(s)
Descubrimiento de Drogas , Piperidinas/farmacología , Receptores CCR1/antagonistas & inhibidores , Relación Dosis-Respuesta a Droga , Humanos , Estructura Molecular , Piperidinas/síntesis química , Piperidinas/química , Relación Estructura-Actividad
20.
J Phys Chem A ; 117(25): 5314-25, 2013 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-23721288

RESUMEN

A series of donor-chromophore-acceptor-stable radical (D-C-A-R(•)) molecules having well-defined molecular structures were synthesized to study the factors affecting electron spin polarization transfer from the photogenerated D(+•)-C-A(-•) spin-correlated radical pair (RP) to the stable radical R(•). Theory suggests that the magnitude of this transfer depends on the spin-spin exchange interaction (2JDA) of D(+•)-C-A(-•). Yet, the generality of this prediction has never been demonstrated. In the D-C-A-R(•) molecules described herein, D is 4-methoxyaniline (MeOAn), 2,3-dihydro-1,4-benzodioxin-6-amine (DioxAn), or benzobisdioxole aniline (BDXAn), C is 4-aminonaphthalene-1,8-dicarboximide, and A is naphthalene-1,8:4,5-bis(dicarboximide) (1A,B-3A,B) or pyromellitimide (4A,B-6A,B). The terminal imide of the acceptors is functionalized with either a hydrocarbon (1A-6A) or a 2,2,6,6-tetramethyl-1-piperidinyloxyl radical (R(•)) (1B-6B). Photoexcitation of C with 416-nm laser pulses results in two-step charge separation to yield D(+•)-C-A(-•)-(R(•)). Time-resolved electron paramagnetic resonance (TREPR) spectroscopy using continuous-wave (CW) microwaves at both 295 and 85 K and pulsed microwaves at 85 K (electron spin-echo detection) was used to probe the initial formation of the spin-polarized RP and the subsequent polarization of the attached R(•) radical. The TREPR spectra show that |2JDA| for D(+•)-C-A(-•) decreases in the order MeOAn(+•) > DioxAn(+•) > BDXAn(+•) as a result of their spin density distributions, whereas the spin-spin dipolar interaction (dDA) remains nearly constant. Given this systematic variation in |2JDA|, electron spin-echo-detected EPR spectra of 1B-6B at 85 K show that the magnitude of the spin polarization transferred from the RP to R(•) depends on |2JDA|.

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