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1.
J Radioanal Nucl Chem ; : 1-16, 2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37360011

RESUMEN

The isolation and purification of protactinium from uranium materials is essential for 231Pa-235U radiochronometry, but separating Pa from uranium-niobium alloys, a common material in the nuclear fuel cycle, is challenging due to the chemical similarity of Pa and Nb. Here we present three resin chromatography separation techniques for isolating Pa from U and Nb which were independently developed by three different laboratories through ad hoc adaptations of standard operating procedures. Our results underscore the need for and value of purification methods suitable for a diversity of uranium-based materials to ensure the operational readiness of nuclear forensics laboratories. Supplementary Information: The online version contains supplementary material available at 10.1007/s10967-023-08928-y.

2.
PhytoKeys ; (59): 1-828, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26929706

RESUMEN

A working checklist of accepted taxa worldwide is vital in achieving the goal of developing an online flora of all known plants by 2020 as part of the Global Strategy for Plant Conservation. We here present the first-ever worldwide checklist for liverworts (Marchantiophyta) and hornworts (Anthocerotophyta) that includes 7486 species in 398 genera representing 92 families from the two phyla. The checklist has far reaching implications and applications, including providing a valuable tool for taxonomists and systematists, analyzing phytogeographic and diversity patterns, aiding in the assessment of floristic and taxonomic knowledge, and identifying geographical gaps in our understanding of the global liverwort and hornwort flora. The checklist is derived from a working data set centralizing nomenclature, taxonomy and geography on a global scale. Prior to this effort a lack of centralization has been a major impediment for the study and analysis of species richness, conservation and systematic research at both regional and global scales. The success of this checklist, initiated in 2008, has been underpinned by its community approach involving taxonomic specialists working towards a consensus on taxonomy, nomenclature and distribution.

3.
PhytoKeys ; (50): 43-60, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26140020

RESUMEN

Brevianthus is a distinctive genus of leafy liverwort in its succubously inserted, entire leaves, lack of underleaves, restriction of sexual organs to lateral-intercalary branches, scattered rhizoids and dense leaf-surface ornamentation. The sole species, Brevianthusflavus, is divided into two subspecies, one in Tasmania the other in New Zealand. A second species, Brevianthushypocanthidium, is described as new and is the first record of the genus for New Caledonia. Among its distinguishing characters are its shallowly bilobed leaves, and triangular underleaves present on small to medium-sized shoot sectors, the lack of a hyaline leaf margin, and the crenulate leaf margin formed by heavily thickened external cell walls. The most unusual features of the new species are the presence of underleaves between lateral leaf insertion lines that reach the ventral stem mid-line, and the absence of underleaves from larger shoots. To explain these features we propose a competitive model of shoot formation wherein the ventral merophyte progressively loses vigor as its relative stature decreases, and its derivative cells become discontinuous and isolated along the ventral stem surface, with intervening areas occupied by derivatives of the more vigorous lateral merophytes.

4.
PhytoKeys ; (50): 101-22, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26140022

RESUMEN

The systematic placement of Frullaniaherzogii has been contentious since its description six decades ago. Over the years it has been interpreted as either a member of the genus Frullania or segregated into its own genus, Neohattoria, due to morphological similarities with both Frullania and Jubula. Here we provide molecular evidence that supports the recognition of the genus Neohattoria and its inclusion within the Jubulaceae, together with Jubula and Nipponolejeunea. Jubulaceae are placed sister to Lejeuneaceae rather than to the monogeneric Frullaniaceae.

5.
J Med Chem ; 57(15): 6781-94, 2014 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-25057800

RESUMEN

A series of novel tetrahydropyridinecarboxamide TRPV1 antagonists were prepared and evaluated in an effort to optimize properties of previously described lead compounds from piperazinecarboxamide series. The compounds were evaluated for their ability to block capsaicin and acid-induced calcium influx in CHO cells expressing human TRPV1. The most potent of these TRPV1 antagonists were further characterized in pharmacokinetic, efficacy, and body temperature studies. On the basis of its pharmacokinetic, in vivo efficacy, safety, and toxicological properties, compound 37 was selected for further evaluation in human clinical trials.


Asunto(s)
Aminopiridinas/química , Analgésicos/química , Dolor/tratamiento farmacológico , Canales Catiónicos TRPV/antagonistas & inhibidores , Aminopiridinas/farmacocinética , Aminopiridinas/farmacología , Analgésicos/farmacocinética , Analgésicos/farmacología , Animales , Temperatura Corporal/efectos de los fármacos , Células CHO , Calcio/metabolismo , Capsaicina/farmacología , Cricetulus , Adyuvante de Freund , Ganglios Espinales/citología , Humanos , Concentración de Iones de Hidrógeno , Masculino , Dolor/etiología , Ratas Sprague-Dawley , Células Receptoras Sensoriales/efectos de los fármacos , Células Receptoras Sensoriales/fisiología , Estereoisomerismo , Relación Estructura-Actividad
6.
Ann Fam Med ; 2(4): 333-40, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15335132

RESUMEN

BACKGROUND: Despite recent attention given to medical errors, little is known about the kinds and importance of medical errors in primary care. The principal aims of this study were to develop patient-focused typologies of medical errors and harms in primary care settings and to discern which medical errors and harms seem to be the most important. METHODS: Thirty-eight in-depth anonymous interviews of adults from rural, suburban, and urban locales in Virginia and Ohio were conducted to solicit stories of preventable problems with primary health care that led to physical or psychological harm. Transcriptions were analyzed to identify, name, and organize the stories of errors and harms. RESULTS: The 38 narratives described 221 problematic incidents that predominantly involved breakdowns in the clinician-patient relationship (n = 82, 37%) and access to clinicians (n = 63, 29%). There were several reports of perceived racism. The incidents were linked to 170 reported harms, 70% of which were psychological, including anger, frustration, belittlement, and loss of relationship and trust in one's clinician. Physical harms accounted for 23% of the total and included pain, bruising, worsening medical condition, and adverse drug reactions. DISCUSSION: The errors reported by interviewed patients suggest that breakdowns in access to and relationships with clinicians may be more prominent medical errors than are technical errors in diagnosis and treatment. Patients were more likely to report being harmed psychologically and emotionally, suggesting that the current preoccupation of the patient safety movement with adverse drug events and surgical mishaps could overlook other patient priorities.


Asunto(s)
Errores Médicos/clasificación , Atención Primaria de Salud , Adulto , Anciano , Femenino , Accesibilidad a los Servicios de Salud , Humanos , Masculino , Errores Médicos/efectos adversos , Errores Médicos/psicología , Persona de Mediana Edad , Participación del Paciente , Satisfacción del Paciente , Relaciones Médico-Paciente , Prejuicio
7.
Qual Health Res ; 13(6): 743-80, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12891714

RESUMEN

In the interest of publicizing examples of funded qualitative health research, the authors share a proposal to the Agency for Healthcare Research and Quality in Washington, D.C., in which they sought to elicit patient stories of preventable problems in their primary health care that were associated with psychological or physical harms. These stories would allow for the construction of a tentative typology of errors and harms as experienced by patients and the contrasting of this with errors and harms reported by primary care physicians in the United States and other countries. The authors make explicit the anticipated concerns of reviewers more accustomed to quantitative research proposals and the arguments and strategies employed to address them.


Asunto(s)
Errores Médicos , Participación del Paciente , Atención Primaria de Salud/normas , Investigación Cualitativa , Garantía de la Calidad de Atención de Salud/métodos , Atención Ambulatoria/normas , Humanos , Narración , Revisión de la Investigación por Pares , Proyectos de Investigación/normas , Estados Unidos
8.
Arch Pediatr Adolesc Med ; 157(5): 490-1; author reply 491-2, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12742890
9.
Am J Emerg Med ; 20(3): 238-42, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11992347

RESUMEN

Left ventricular aneurysm (LVA), also described as dyskinetic left ventricular segment, is defined as a localized area of infarcted myocardium that bulges outward during both systole and diastole. LVAs most often are noted after large anterior wall events but may also be encountered status after inferior and posterior wall injuries. In most cases, LVA is manifested electrocardiographically by varying degrees of ST segment elevation (STE), which may be difficult to distinguish from ST segment changes caused by acute myocardial infarction. The STE is generally associated with well-developed, completed Q waves in the anterior precordial leads, and there will not be reciprocal ST depression in the contralateral leads. This article focuses on the electrocardiographic findings useful in making the diagnosis of left ventricular aneurysm as well as distinguishing LVA from other STE syndromes.


Asunto(s)
Arritmias Cardíacas/etiología , Electrocardiografía , Aneurisma Cardíaco/diagnóstico , Ventrículos Cardíacos/fisiopatología , Anciano , Diagnóstico Diferencial , Femenino , Aneurisma Cardíaco/complicaciones , Aneurisma Cardíaco/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico
10.
J Med Humanit ; 18(3): 193-208, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-11654862

RESUMEN

This study describes the results of a retrospective review of patients' charts who had an advanced directive (AD) and who were hospitalized in a tertiary, acute care teaching hospital. The purpose of the review was to understand from clinical, sociological, ethical and legal perspectives the nature and utility of ADs. Findings and implications of the review are discussed in terms of: patient demographics; diagnoses; quality of ADs; influence of ADs on clinical decisions; and legal aspects of ADs.


Asunto(s)
Directivas Anticipadas , Toma de Decisiones , Estudios de Evaluación como Asunto , Hospitales , Síndrome de Inmunodeficiencia Adquirida , Factores de Edad , Eutanasia Pasiva , Familia , Hospitales de Enseñanza , Humanos , Jurisprudencia , Voluntad en Vida , Registros Médicos , Competencia Mental , Mid-Atlantic Region , Morbilidad , Cuidados Paliativos , Atención al Paciente , Médicos , Pronóstico , Estándares de Referencia , Religión , Órdenes de Resucitación , Estudios Retrospectivos , Enfermo Terminal , Consentimiento por Terceros , Estados Unidos , Privación de Tratamiento
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