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1.
Langmuir ; 33(19): 4748-4757, 2017 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-28437114

RESUMEN

Quasi-monodisperse populations of (H3O)Y3F10·xH2O nanocrystals of varying size are prepared in Igepal-stabilized microemulsions. Correlations between microemulsion composition, micelle hydrodynamic radius, and final nanoparticle size are established and shed light on the mechanism of particle size control. Under the conditions considered here, size control appears to be primarily governed by the number of micelles and the quantities of precursor ions. More specifically, the number of NPs formed can be successfully correlated with the number of micelles present and final NP size is, in turn, determined by the number of nuclei and the total amount of material available for nanocrystal formation. This insight into nanoparticle formation facilitates the selection of appropriate synthetic conditions for the preparation of populations of a targeted size.

3.
Phys Rev Lett ; 114(17): 171301, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25978223

RESUMEN

Models such as Natural Inflation that use pseudo-Nambu-Goldstone bosons as the inflaton are attractive for many reasons. However, they typically require trans-Planckian field excursions ΔΦ>MPl, due to the need for an axion decay constant f>MPl to have both a sufficient number of e-folds and values of ns,r consistent with data. Such excursions would in general require the addition of all other higher dimension operators consistent with symmetries, thus disrupting the required flatness of the potential and rendering the theory nonpredictive. We show that in the case of Natural Inflation, the existence of spinodal instabilities (modes with tachyonic masses) can modify the inflaton equations of motion to the point that versions of the model with f

4.
J Clin Anesth ; 98: 111560, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39146724

RESUMEN

STUDY OBJECTIVE: The aim of this study was to investigate the efficacy of a two-step patient blood management (PBM) program in red blood cell (RBC) transfusion requirements among patients undergoing elective cardiopulmonary bypass (CPB) surgery. DESIGN: Prospective, non-randomized, two-step protocol design. SETTING: Cardiac surgery department of Clinique Pasteur, Toulouse, France. PATIENTS: 897 patients undergoing for elective CPB surgery. INTERVENTIONS: We conducted a two-steps protocol: PBMe and PBMc. PBMe involved a short quality improvement program for health care workers, while PBMc introduced a systematic approach to pre- and postoperative correction of deficiencies, incorporating iron injections, oral vitamins, and erythropoiesis-stimulating agents. MEASUREMENTS: The PBM program's effectiveness was evaluated through comparison with a pre-PBM retrospective cohort after propensity score matching. The primary objective was the proportion of patients requiring RBC transfusions during their hospital stay. Secondary objectives were also analyzed. MAIN RESULTS: After matching, 343 patients were included in each group. Primary outcomes were observed in 35.7% (pre-PBM), 26.7% (PBMe), and 21.1% (PBMc) of patients, resulting in a significant reduction (40.6%) in the overall RBC transfusion rate. Both the PBMe and PBMc groups exhibited significantly lower risks of RBC transfusion compared to the pre-PBM group, with adjusted odds ratios of 0.59 [95% CI 0.44-0.79] and 0.44 [95% CI 0.32-0.60], respectively. Secondary endpoints included reductions in transfusions exceeding 2 units, total RBC units transfused, administration of allogeneic blood products, and total bleeding volume recorded on Day 1. There were no significant differences noted in mortality rates or the duration of hospital stays. CONCLUSIONS: This study suggests that health care education and systematic deficiency correction are associated with reduced RBC transfusion rates in elective CPB surgery. However, further randomized, controlled studies are needed to validate these findings and refine their clinical application.


Asunto(s)
Puente Cardiopulmonar , Procedimientos Quirúrgicos Electivos , Transfusión de Eritrocitos , Atención Perioperativa , Humanos , Transfusión de Eritrocitos/estadística & datos numéricos , Masculino , Femenino , Estudios Prospectivos , Procedimientos Quirúrgicos Electivos/efectos adversos , Anciano , Persona de Mediana Edad , Atención Perioperativa/métodos , Puente Cardiopulmonar/efectos adversos , Anemia Ferropénica/prevención & control , Hematínicos/administración & dosificación , Anemia/terapia , Mejoramiento de la Calidad , Deficiencias de Hierro , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Estudios Retrospectivos , Hierro/administración & dosificación , Francia , Tiempo de Internación/estadística & datos numéricos
6.
Contemp Clin Trials Commun ; 19: 100617, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32695923

RESUMEN

Anaemia and iron deficiency are frequent in patients scheduled for cardiac surgery. Perioperative patient blood management (PBM) is widely recommended in current practice guidelines. The aim of this protocol is to analyse the effect of a global perioperative PBM programme on the red blood cell (RBC) transfusion ratio, morbidities and rehabilitation score in elective cardiac surgery.This study is a prospective, single-centre trial with a 2-step protocol, A and B, as follows: A: non-drug intervention: the caregiver is given a blood management educational programme; B: drug intervention: systematic correction of perioperative iron, vitamin deficiencies, and anaemia. This study was designed to enrol 900 patients (500 in group A and 400 in group B) in a rolling period starting at anaesthesia consultation and ending 3 months after surgery. The primary objective was a 20% reduction in RBC transfusion after implementation of PBM programmes (protocol A + B) when compared to our previous transfusion ratio in the first half of 2018 (30.4% vs 38%). The secondary objectives were to evaluate the impact for each step of the study on the RBC transfusion rate, morbidity and the quality of postoperative rehabilitation.The strength of this study is its evaluation of the effect of a global PBM programme on RBC transfusion in cardiac surgery through a 2-step protocol. We aim to assess for the first time the impact of non-drug and drug interventions on RBC transfusion, comorbidities and delayed rehabilitation parameters. TRIALS REGISTRATIONS: ClinicalTrials.gov, NCT04040023: registered 29 July 2019.

7.
J Pain Symptom Manage ; 29(2): 130-55, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15733806

RESUMEN

Research on comorbidity across cancer symptoms, including pain, fatigue, and depression, could suggest if crossover effects from symptom-specific interventions are plausible. Secondary analyses were conducted on a survey of 268 cancer patients with recurrent disease from a northeastern U.S. city who were initiating palliative radiation for bone pain. Moderator regression analyses predicted variation in depressive affect that could be attributed to symptom clusters. Patients self-reported difficulty controlling each physical symptom over the past month on a Likert scale and depressive symptoms on a validated depression measure (Center for Epidemiologic Studies-Depression [CES-D]) over the past week on a four-category scale. An index of depressive affect was based on items of negative and positive affect from the CES-D. In predicting depressive affect, synergistic interactions of pain with fever, fatigue, and weight loss suggest separate pathways involving pain. A similar interaction with fever occurs when nausea was tested in place of pain. Further, the interaction between pain and fatigue is similar in form to the interaction between difficulty breathing and fatigue (when sleep is not a problem). Follow-up to the latter interaction reveals: 1) additional moderation by hypertension and palliative radiation to the hip/pelvis; and 2) a similar cluster not involving hypertension when appetite problems and weight loss were tested in place of fatigue. The significance and form of these interactions are remarkably consistent. Similar sickness mechanisms could be generating: 1) pain and nausea during fever; 2) pain and fatigue during weight loss; and 3) pain and breathing difficulty when fatigue is pronounced. Crossover effects from symptom-specific interventions appear promising.


Asunto(s)
Neoplasias Óseas/epidemiología , Neoplasias Óseas/radioterapia , Trastorno Depresivo/epidemiología , Dolor/epidemiología , Dolor/prevención & control , Cuidados Paliativos/estadística & datos numéricos , Medición de Riesgo/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Óseas/secundario , Comorbilidad , Recolección de Datos , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Factores de Riesgo , Estadística como Asunto , Estados Unidos/epidemiología
8.
PLoS One ; 5(12): e15629, 2010 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-21206917

RESUMEN

The widely studied and invasive earthworm, Lumbricus terrestris L., 1758 has been the subject of nomenclatural debate for many years. However these disputes were not based on suspicions of heterogeneity, but rather on the descriptions and nomenclatural acts associated with the species name. Large numbers of DNA barcode sequences of the cytochrome oxidase I obtained for nominal L. terrestris and six congeneric species reveal that there are two distinct lineages within nominal L. terrestris. One of those lineages contains the Swedish population from which the name-bearing specimen of L. terrestris was obtained. The other contains the population from which the syntype series of Enterion herculeum Savigny, 1826 was collected. In both cases modern and old representatives yielded barcode sequences allowing us to clearly establish that these are two distinct species, as different from one another as any other pair of congeners in our data set. The two are morphologically indistinguishable, except by overlapping size-related characters. We have designated a new neotype for L. terrestris. The newly designated neotype and a syntype of L. herculeus yielded DNA adequate for sequencing part of the cytochrome oxidase I gene (COI). The sequence data make possible the objective determination of the identities of earthworms morphologically identical to L. terrestris and L. herculeus, regardless of body size and segment number. Past work on nominal L. terrestris could have been on either or both species, although L. herculeus has yet to be found outside of Europe.


Asunto(s)
Código de Barras del ADN Taxonómico/métodos , ADN/genética , Oligoquetos/genética , Animales , Secuencia de Bases , Biodiversidad , Canadá , Biología Computacional/métodos , Dinamarca , Complejo IV de Transporte de Electrones/metabolismo , Modelos Genéticos , Datos de Secuencia Molecular , Noruega , Análisis de Secuencia de ADN/métodos
9.
Am J Geriatr Psychiatry ; 14(3): 228-36, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16505127

RESUMEN

OBJECTIVE: There is inconsistent evidence for the validity of a single item to screen depression. In inner-city minority populations, the "yes/no" forced-response option may encourage bias, especially in elders and men, who view depression as stigmatizing or the healthcare system as untrustworthy. In contrast, an open-choice format with a category for ambivalent and missing responses could be acceptable if administered during the legitimized context of a physical symptom assessment. METHOD: Retrospective data were analyzed from 146 black and Latino inner-city patients receiving palliative care for various physical conditions. Bivariate analyses and ordinal regressions are based on the most recent comprehensive patient assessment conducted by a black female nurse and a bilingual Latina social worker. RESULTS: The depression item (no, unknown, yes) predicts pain and symptom attitude, which is more "hopeful" in older men with unknown depression status than in younger and older women with unknown depression status or no depression. CONCLUSIONS: The more "hopeful" pain and symptom attitudes by older men in the unknown category for depression suggest that depression, apathy, and resignation in older minority men may be hidden from clinicians in the absence of the open-choice depression item.


Asunto(s)
Población Negra/psicología , Trastorno Depresivo/diagnóstico , Hispánicos o Latinos/psicología , Cuidados Paliativos/psicología , Determinación de la Personalidad/estadística & datos numéricos , Rol del Enfermo , Población Urbana , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Población Negra/estadística & datos numéricos , Trastorno Depresivo/epidemiología , Femenino , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Motivación , Ciudad de Nueva York , Dolor/diagnóstico , Dolor/psicología , Psicometría/estadística & datos numéricos , Reproducibilidad de los Resultados , Factores Sexuales , Estadística como Asunto
10.
Acta Oncol ; 44(4): 369-81, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16120546

RESUMEN

Objective financial stress, which incorporates all medical and non-medical financial stressors by households, shapes patients' subjective perceptions of financial strain. This study addresses whether patient age and disability days reveal patients to have different perceptions of financial strain even when their households incur the same level of financial stress. Among patients with the same level of household financial stress, older patients perceived less financial strain from difficulty paying bills than younger patients. However, among patients reporting above-average disability days, older patients also perceived more financial strain than younger patients about the adequacy of their health insurance and finances in the future. Thus, financial strain measures that focus on projected health needs should supplement those that describe current household circumstances to improve screenings of older patients who are under-prescribed, or unable to adhere to, a regimen for all necessary health care.


Asunto(s)
Envejecimiento , Personas con Discapacidad/psicología , Costos de la Atención en Salud , Neoplasias/economía , Neoplasias/radioterapia , Cuidados Paliativos/economía , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Actitud Frente a la Salud , Femenino , Humanos , Masculino , Programas Controlados de Atención en Salud/economía , Persona de Mediana Edad , Estrés Psicológico/economía
11.
Res Aging ; 24(4): 445-472, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-18443643

RESUMEN

Income-equivalence scales (IES) provide distinct advantages over poverty indices to adjust family income for differences in family size, including improved specification of hypothesized causal relationships involving objective measures of economic well-being. In a novel IES application, cancer patients' out-of-pocket health costs are adjusted for differences in family income and size and, along with five other subindices, contribute to an overall index of "objective family financial stress." Age-related changes are modeled simultaneously within relationships between overall objective family financial stress and subjective patient perceptions about financial strain. Among the findings, the impact of age on one area of subjective financial strain, "difficulty paying bills," is negative and curvilinear. Regardless of adjusted out-of-pocket costs, as age advances, patients appear increasingly likely to accommodate to financial stress by reporting less difficulty paying bills. This phenomenon could serve to mask and isolate older adults who are foregoing needed yet unaffordable medical care and prescriptions.

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