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1.
AIDS ; 38(9): 1439-1442, 2024 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-38932749

RESUMEN

Women living with HIV and breast cancer have poorer survival than HIV-negative women. Efavirenz-estrogen interactions are documented; however, the survival impact is unknown. Survival between women with estrogen-receptor positive breast cancer taking efavirenz (n = 38) and nonefavirenz regimens (n = 51) were compared. The 5-year overall-survival was 48.9% [95% confidence interval (CI) 33.0-72.2 and 51.1% (95% CI 34.0-76.8)] in the efavirenz and nonefavirenz groups, respectively suggesting efavirenz is unlikely driving poorer survival in women living with HIV and estrogen-receptor positive breast cancer.


Asunto(s)
Alquinos , Fármacos Anti-VIH , Benzoxazinas , Neoplasias de la Mama , Ciclopropanos , Infecciones por VIH , Humanos , Benzoxazinas/uso terapéutico , Ciclopropanos/uso terapéutico , Femenino , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/tratamiento farmacológico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/mortalidad , Infecciones por VIH/complicaciones , Persona de Mediana Edad , Adulto , Fármacos Anti-VIH/uso terapéutico , Análisis de Supervivencia , Anciano
2.
Lancet Microbe ; 5(5): e433-e441, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38461830

RESUMEN

BACKGROUND: Despite increasing availability of rapid molecular tests for the diagnosis of tuberculosis in high-burden settings, many people with tuberculosis are undiagnosed. Reliance on sputum as the primary specimen for tuberculosis diagnostics contributes to this diagnostic gap. We evaluated the diagnostic accuracy and additive yield of a novel stool quantitative PCR (qPCR) assay for the diagnosis of tuberculosis in three countries in Africa with high tuberculosis burdens. METHODS: We undertook a prospective diagnostic accuracy study in Eswatini, Mozambique, and Tanzania from Sept 21, 2020, to Feb 2, 2023, to compare the diagnostic accuracy for tuberculosis of a novel stool qPCR test with the current diagnostic standard for Mycobacterium tuberculosis DNA detection from sputum and stool, Xpert-MTB/RIF Ultra (Xpert Ultra). Sputum, stool, and urine samples were provided by a cohort of participants, aged 10 years or older, diagnosed with tuberculosis. Participants with tuberculosis (cases) were enrolled within 72 h of treatment initiation for tuberculosis diagnosed clinically or following laboratory confirmation. Participants without tuberculosis (controls) consisted of household contacts of the cases who did not develop tuberculosis during a 6-month follow-up. The performance was compared with a robust composite microbiological reference standard (CMRS). FINDINGS: The cohort of adolescents and adults (n=408) included 268 participants with confirmed or clinical tuberculosis (cases), 147 (55%) of whom were living with HIV, and 140 participants (controls) without tuberculosis. The sensitivity of the novel stool qPCR was 93·7% (95% CI 87·4-97·4) compared with participants with detectable growth on M tuberculosis culture, and 88·1% (81·3-93·0) compared with sputum Xpert Ultra. The stool qPCR had an equivalent sensitivity as sputum Xpert Ultra (94·8%, 89·1-98·1) compared with culture. Compared with the CMRS, the sensitivity of the stool qPCR was higher than the current standard for tuberculosis diagnostics on stool, Xpert Ultra (80·4%, 73·4-86·2 vs 73·5%, 66·0-80·1; p=0·025 on paired comparison). The qPCR also identified 17-21% additional tuberculosis cases compared to sputum Xpert Ultra or sputum culture. In controls without tuberculosis, the specificity of the stool qPCR was 96·9% (92·2-99·1). INTERPRETATION: In this study, a novel qPCR for the diagnosis of tuberculosis from stool specimens had a higher accuracy in adolescents and adults than the current diagnostic PCR gold standard on stool, Xpert-MTB/RIF Ultra, and equivalent sensitivity to Xpert-MTB/RIF Ultra on sputum. FUNDING: National Institutes of Health (NIH) Allergy and Infectious Diseases, and NIH Fogarty International Center.


Asunto(s)
Heces , Mycobacterium tuberculosis , Reacción en Cadena en Tiempo Real de la Polimerasa , Sensibilidad y Especificidad , Esputo , Tuberculosis , Humanos , Adolescente , Heces/microbiología , Heces/química , Adulto , Estudios Prospectivos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Femenino , Masculino , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Adulto Joven , Tuberculosis/diagnóstico , Tuberculosis/microbiología , Tuberculosis/orina , Esputo/microbiología , Persona de Mediana Edad , Niño , Tanzanía/epidemiología , ADN Bacteriano/análisis , Mozambique/epidemiología
3.
J Allergy Clin Immunol Pract ; 12(2): 364-371.e1, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37923127

RESUMEN

BACKGROUND: Undertreatment of anaphylaxis with epinephrine continues to be an unmet need and is a particular challenge among infants and toddlers. OBJECTIVE: To address this gap by identifying barriers and solutions to appropriate and timely administration of epinephrine. METHODS: We conducted a national online survey among primary caregivers of children who experienced a severe food-induced allergic reaction when younger than 36 months. Outcomes of interest included epinephrine use in community and health care settings to treat probable anaphylaxis. RESULTS: Of 264 probable anaphylaxis cases, 39% of infants (aged <12 months) and 61% of toddlers (aged 12-35 months) received epinephrine at any time during the child's most severe allergic reaction (P = .001). A previous diagnosis of a food allergy was reported in 62% of cases where epinephrine was used compared with 26% of cases where epinephrine was not used (P < .001). In children with a previous diagnosis of a food allergy, epinephrine was used in 89% of those who were prescribed an anaphylaxis action plan compared with 50% of those without a plan (P = .001). The adjusted odds ratio for the association between having an anaphylaxis action plan and epinephrine use in cases of probable anaphylaxis was 5.39 (95% confidence interval, 2.18-13.30). CONCLUSIONS: Epinephrine use at any time (including in health care settings) during probable anaphylaxis is more likely in infants and toddlers with a previously diagnosed food allergy than those without diagnosis. The provision of an anaphylaxis action plan is also associated with increased epinephrine use during probable anaphylaxis in this population.


Asunto(s)
Anafilaxia , Hipersensibilidad a los Alimentos , Lactante , Humanos , Preescolar , Anafilaxia/tratamiento farmacológico , Anafilaxia/epidemiología , Anafilaxia/complicaciones , Epinefrina/uso terapéutico , Hipersensibilidad a los Alimentos/tratamiento farmacológico , Hipersensibilidad a los Alimentos/epidemiología , Hipersensibilidad a los Alimentos/complicaciones
4.
Pediatr Infect Dis J ; 42(7): 576-581, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-36795586

RESUMEN

BACKGROUND: Despite encouraging results from clinical trials and in high-income countries, large-scale data on the effectiveness and safety of dolutegravir (DTG) in children and adolescents living with HIV (CALHIV) are lacking in low- and middle-income countries (LMICs). METHODS: Retrospective analysis was performed among CALHIV 0-19 years old and weighing greater than or equal to 20 kg who received DTG from 2017 to 2020 at sites in Botswana, Eswatini, Lesotho, Malawi, Tanzania and Uganda to determine effectiveness, safety and predictors of viral load suppression (VLS) among CALHIV using DTG, including through single drug substitutions (SDS). RESULTS: Among 9419 CALHIV using DTG, 7898 had a documented post-DTG VL, and VLS post-DTG was 93.4% (7378/7898). VLS for antiretroviral therapy (ART) initiations was 92.4% (246/263), and VLS was maintained for the ART-experienced [92.9% (7026/7560) pre- vs. 93.5% (7071/7560) post-DTG; P = 0.14). Among previously unsuppressed, 79.8% (426/534) achieved VLS with DTG. Only 5 patients reported a Grade 3 or 4 adverse event (0.057 per 100 patient-years) requiring DTG discontinuation. History of protease inhibitor-based ART [odds ratio (OR) = 1.53; 95% confidence interval (CI): 1.16-2.03], care in Tanzania (OR = 5.45; 95% CI: 3.41-8.70), and being 15-19 years old (OR = 1.31; 95% CI: 1.03-1.65) were associated with gain of VLS post-DTG. Predictors of VLS on DTG included VLS before DTG (OR = 3.87; 95% CI: 3.03-4.95) and using the once-daily, single tab tenofovir-lamivudine-DTG regimen (OR = 1.78; 95% CI: 1.43-2.22). SDS maintained VLS [95.9% (2032/2120) pre- vs. 95.0% (2014/2120) post-SDS with DTG; P = 0.19], and 83.0% (73/88) of unsuppressed gained VLS using SDS with DTG. CONCLUSIONS: We found DTG to be highly effective and safe within our cohort of CALHIV in LMICs. These findings can empower clinicians to prescribe DTG confidently to eligible CALHIV.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Humanos , Adolescente , Niño , Recién Nacido , Lactante , Preescolar , Adulto Joven , Adulto , Fármacos Anti-VIH/efectos adversos , Estudios Retrospectivos , Infecciones por VIH/tratamiento farmacológico , Compuestos Heterocíclicos con 3 Anillos/efectos adversos , África Austral , Carga Viral
5.
Clin Infect Dis ; 76(1): 10-17, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36097966

RESUMEN

BACKGROUND: There is insufficient evidence in children and adolescents with human immunodeficiency virus (CAHIV) to guide the timing of antiretroviral treatment (ART) initiation after starting treatment for pulmonary tuberculosis (pTB). To address this knowledge gap, we evaluated the risk of mortality associated with timing of ART initiation in ART-naive CAHIV treated for pTB. METHODS: Data were extracted from electronic medical records of ART-naive patients, aged 0-19 years, who were treated for HIV-associated pTB at Baylor Centers of Excellence in Botswana, Eswatini, Malawi, Lesotho, Tanzania, or Uganda between 2013 and 2020. Data were analyzed against a primary outcome of all-cause mortality with unadjusted Kaplan-Meier curves and Cox proportional hazard models. RESULTS: The study population included 774 CAHIV with variable intervals to ART initiation after starting TB treatment: <2 weeks (n = 266), 2 weeks to 2 months (n = 398), >2 months (n = 66), and no ART initiated (n = 44). Adjusted Cox proportional hazards models demonstrated increased mortality 1 year from TB treatment initiation in children never starting ART (adjusted HR [aHR]: 2.67; 95% CI: 1.03, 6.94) versus children initiating ART between 2 weeks and 2 months from TB treatment initiation. Mortality risk did not differ for the <2-weeks group (aHR: 1.02; 95% CI: .55, 1.89) versus the group initiating ART between 2 weeks and 2 months. CONCLUSIONS: This retrospective study demonstrated no increase in mortality among CAHIV initiating ART <2 weeks from TB treatment initiation. Given the broad health benefits of ART, this evidence supports the recent WHO recommendation for CAHIV to initiate ART within 2 weeks of initiating TB treatment.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Tuberculosis Pulmonar , Humanos , Niño , Adolescente , VIH , Estudios Retrospectivos , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Tuberculosis Pulmonar/complicaciones , Tuberculosis Pulmonar/tratamiento farmacológico , Antirretrovirales/uso terapéutico , Modelos de Riesgos Proporcionales , Fármacos Anti-VIH/uso terapéutico
6.
J Allergy Clin Immunol Pract ; 9(1): 311-320.e2, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33217612

RESUMEN

BACKGROUND: Recognizing anaphylaxis in infants and toddlers can be challenging for health care providers and caregivers, and current diagnostic criteria and anaphylaxis action plans do not specifically address this younger population. OBJECTIVE: To describe symptoms and signs observed by primary caregivers of infants and toddlers during severe food-induced allergic reactions. METHODS: We conducted a national online survey among primary caregivers of children who experienced a severe food-induced allergic reaction when less than 36 months of age. Respondents who were present during the child's most severe reaction were asked to report symptoms and signs observed. The survey asked about infant- and toddler-specific symptoms and signs in lay language for caregivers. Data were compared with patient-reported data from past studies to identify distinct patterns among the younger population. RESULTS: The survey was completed for 374 children (193 infants, 181 toddlers). The most common symptoms and signs reported were skin reactions (90%), facial and extremity swelling (59%), gastrointestinal issues (51%), and coughing/wheezing (45%). Infants (aged <12 months) more frequently experienced skin reactions, skin mottling, and ear pulling/scratching or putting fingers in ears, as compared with toddlers (aged 12-35 months). Toddlers experienced throat itching and coughing/wheezing more frequently than infants. CONCLUSIONS: Anaphylaxis presentation demonstrates similarities and differences in infants and toddlers. Modifying the terminology used in the current criteria allowed for reporting of symptoms and signs of anaphylaxis that are more common in infants and toddlers. Diagnostic criteria, clinical guidelines, and anaphylaxis action plans may be enhanced to address this young, often nonverbal, population.


Asunto(s)
Anafilaxia , Hipersensibilidad a los Alimentos , Alérgenos , Anafilaxia/diagnóstico , Anafilaxia/epidemiología , Cuidadores , Preescolar , Alimentos , Hipersensibilidad a los Alimentos/diagnóstico , Hipersensibilidad a los Alimentos/epidemiología , Humanos , Lactante
7.
J Surg Res ; 247: 547-555, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31740011

RESUMEN

BACKGROUND: With advances in cross-sectional imaging, pancreatic cysts are more frequently diagnosed and have become a common indication for pancreatectomy. The impact of pancreatectomy in these patients is important. The purpose of this study was to assess short-term outcomes, long-term nutritional status, quality of life (QOL), and pancreas function after pancreatectomy for cystic neoplasms. MATERIALS AND METHODS: At a single institution, patients at least 3 y post-pancreatectomy for benign cystic neoplasms were identified. Using a validated questionnaire, short-term outcomes, long-term outcomes including endocrine and exocrine insufficiency, long-term nutritional status, and preoperative and postoperative QOL were compared based on operation and indication for resection. RESULTS: Among 102 eligible patients, 70 had valid contact information and 51 (72.9%) agreed to participate. Median follow-up was 6 (4-8) y. Patients undergoing pancreatoduodenectomy for benign cysts had higher morbidity than a similar cohort resected for pancreatic adenocarcinoma (patients with at least 1 ≥ grade 2 complication [49.0% versus 31.6%, P = 0.038]). After long-term follow-up, pancreatectomy did not significantly affect perceived QOL. Half of patients had mild-moderate or severe malnourishment, but pancreatic enzyme replacement was reported by only 4 (7.8%) patients. New-onset diabetes was present in 15 (29.4%) patients with median time-to-diagnosis of 6 (1-12) mo after resection. CONCLUSIONS: Pancreatectomy for benign cysts did not negatively impact patients' perceived QOL. However, after long-term follow-up, malnutrition and pancreatic insufficiency occurred in a significant percentage and may be greater than previously estimated. Consideration of short- and long-term outcomes should factor into preoperative counseling, especially in cysts with minimal risk of progression to malignancy.


Asunto(s)
Carcinoma Ductal Pancreático/cirugía , Quiste Pancreático/cirugía , Neoplasias Pancreáticas/cirugía , Pancreaticoduodenectomía/efectos adversos , Complicaciones Posoperatorias/epidemiología , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estado Nutricional , Medición de Resultados Informados por el Paciente , Complicaciones Posoperatorias/etiología , Estudios Prospectivos , Calidad de Vida , Resultado del Tratamiento
8.
J Surg Res ; 228: 271-280, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29907222

RESUMEN

BACKGROUND: Addition of en bloc segmental venous reconstruction (VR) to pancreaticoduodenectomy (PD) for venous involvement of pancreatic tumors increases the complexity of the operation and may increase complications. The long-term mesenteric venous patency rate and oncologic outcome has not been well defined. METHODS: Our prospective database was reviewed to assess 90-day postoperative outcomes for patients who underwent PD or PD + VR (September 2004-June 2016). Two independent observers reviewed CT scans to determine long-term vein patency. In patients with pancreatic ductal adenocarcinoma, the impact of VR on 5-year overall survival was assessed using multivariate Cox proportional hazards regression. Student's t-test was used to evaluate continuous variables and the chi-square test for categorical variables. RESULTS: Three hundred ninety-three patients underwent PD (51 PD + VR). Patients undergoing PD + VR had longer operations (561 ± 119 versus 433 ± 89 min, P < 0.00001) and greater blood loss (768 ± 812 versus 327 ± 423 cc, P < 0.00001). There was no difference in 90-day mortality, overall postoperative complication rates, complication severity grades, reoperation, readmission, or length of stay. 26.7% experienced venous thrombosis. Most thromboses occurred in the first year after surgery, but we also observed late thrombosis in 1 patient after 89-month follow-up. Among 135 patients with pancreatic ductal adenocarcinoma, survival was significantly longer in the PD-alone group (31.3 months [95% confidence interval: 22.9-40.0] versus 17.0 [95% confidence interval: 13.0-19.1], plog-rank = 0.013). CONCLUSIONS: PD + VR does not increase short-term morbidity, but venous thrombosis is frequent and can occur long after surgery. Survival is inferior when VR is required especially in the absence of neoadjuvant chemotherapy.


Asunto(s)
Carcinoma Ductal Pancreático/cirugía , Venas Mesentéricas/cirugía , Neoplasias Pancreáticas/cirugía , Pancreaticoduodenectomía/efectos adversos , Procedimientos de Cirugía Plástica/efectos adversos , Complicaciones Posoperatorias/epidemiología , Trombosis de la Vena/epidemiología , Anciano , Anastomosis Quirúrgica/efectos adversos , Anastomosis Quirúrgica/métodos , Pérdida de Sangre Quirúrgica/estadística & datos numéricos , Carcinoma Ductal Pancreático/mortalidad , Femenino , Estudios de Seguimiento , Mortalidad Hospitalaria , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/mortalidad , Pancreaticoduodenectomía/métodos , Readmisión del Paciente/estadística & datos numéricos , Complicaciones Posoperatorias/etiología , Estudios Prospectivos , Procedimientos de Cirugía Plástica/métodos , Reoperación/estadística & datos numéricos , Estudios Retrospectivos , Análisis de Supervivencia , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Grado de Desobstrucción Vascular , Trombosis de la Vena/diagnóstico por imagen , Trombosis de la Vena/etiología
9.
HPB (Oxford) ; 20(6): 514-520, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29478737

RESUMEN

BACKGROUND: Although used as criterion for early drain removal, postoperative day (POD) 1 drain fluid amylase (DFA) ≤ 5000 U/L has low negative predictive value for clinically relevant postoperative pancreatic fistula (CR-POPF). It was hypothesized that POD3 DFA ≤ 350 could provide further information to guide early drain removal. METHODS: Data from a pancreas surgery consortium database for pancreatoduodenectomy and distal pancreatectomy patients were analyzed retrospectively. Those patients without drains or POD 1 and 3 DFA data were excluded. Patients with POD1 DFA ≤ 5000 were divided into groups based on POD3 DFA: Group A (≤350) and Group B (>350). Operative characteristics and 60-day outcomes were compared using chi-square test. RESULTS: Among 687 patients in the database, all data were available for 380. Fifty-five (14.5%) had a POD1 DFA > 5000. Among 325 with POD1 DFA ≤ 5000, 254 (78.2%) were in Group A and 71 (21.8%) in Group B. Complications (35 (49.3%) vs 87 (34.4%); p = 0.021) and CR-POPF (13 (18.3%) vs 10 (3.9%); p < 0.001) were more frequent in Group B. CONCLUSIONS: In patients with POD1 DFA ≤ 5000, POD3 DFA ≤ 350 may be a practical test to guide safe early drain removal. Further prospective testing may be useful.


Asunto(s)
Amilasas/metabolismo , Pruebas Enzimáticas Clínicas , Remoción de Dispositivos/métodos , Drenaje/instrumentación , Pancreatectomía , Pancreaticoduodenectomía , Tiempo de Tratamiento , Adulto , Anciano , Biomarcadores/metabolismo , Bases de Datos Factuales , Remoción de Dispositivos/efectos adversos , Drenaje/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pancreatectomía/efectos adversos , Fístula Pancreática/etiología , Fístula Pancreática/prevención & control , Pancreaticoduodenectomía/efectos adversos , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
10.
Ann Surg ; 266(3): 421-431, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28692468

RESUMEN

OBJECTIVE: The objective of this study was to test the hypothesis that distal pancreatectomy (DP) without intraperitoneal drainage does not affect the frequency of grade 2 or higher grade complications. BACKGROUND: The use of routine intraperitoneal drains during DP is controversial. Prior to this study, no prospective trial focusing on DP without intraperitoneal drainage has been reported. METHODS: Patients undergoing DP for all causes at 14 high-volume pancreas centers were preoperatively randomized to placement of a drain or no drain. Complications and their severity were tracked for 60 days and mortality for 90 days. The study was powered to detect a 15% positive or negative difference in the rate of grade 2 or higher grade complications. All data were collected prospectively and source documents were reviewed at the coordinating center to confirm completeness and accuracy. RESULTS: A total of 344 patients underwent DP with (N = 174) and without (N = 170) the use of intraperitoneal drainage. There were no differences between cohorts in demographics, comorbidities, pathology, pancreatic duct size, pancreas texture, or operative technique. There was no difference in the rate of grade 2 or higher grade complications (44% vs. 42%, P = 0.80). There was no difference in clinically relevant postoperative pancreatic fistula (18% vs 12%, P = 0.11) or mortality (0% vs 1%, P = 0.24). DP without routine intraperitoneal drainage was associated with a higher incidence of intra-abdominal fluid collection (9% vs 22%, P = 0.0004). There was no difference in the frequency of postoperative imaging, percutaneous drain placement, reoperation, readmission, or quality of life scores. CONCLUSIONS: This prospective randomized multicenter trial provides evidence that clinical outcomes are comparable in DP with or without intraperitoneal drainage.


Asunto(s)
Drenaje , Pancreatectomía/métodos , Complicaciones Posoperatorias/prevención & control , Anciano , Drenaje/métodos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Prospectivos
11.
Phys Chem Chem Phys ; 17(33): 21525-32, 2015 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-26219752

RESUMEN

Several techniques for obtaining ZnO nanowires (ZnO NWs) have been reported in the literature. In particular, vapour-liquid-solid (VLS) with Au as a catalyst is widely used. During this process, Au impurities in the ZnO NWs can be incorporated accidentally, and for this reason we named these impurities as intruders. It is thought that these intruders may produce interesting alterations in the electronic characteristics of nanowires. In the experiment, it is not easy to detect either Au atoms in these nanowires, or the modification that intruders produce in different electrical, optical and other properties. For this reason, in this density functional theory investigation, the effect of Au intruders on ZnO NWs is analysed. Au extended (thread) and point defects (atoms replacing Zn or O, or Au interstitials) are used to simulate the presence of gold atoms. Optimised geometries, band-gaps and density of states indicate that the presence of small amounts of Au drastically modifies the electronic states of ZnO NWs. The results reported here clearly indicate that small amounts of Au have a strong impact on the electronic properties of ZnO NWs, introducing states in the band edges that may promote transitions in the visible spectral region. The presence of Au as an intruder in ZnO NWs enhances the potential use of this system for photonic and photovoltaic applications.


Asunto(s)
Oro/química , Nanocables/química , Óxido de Zinc/química , Catálisis , Teoría Cuántica
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