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1.
Br J Clin Pharmacol ; 90(1): 164-175, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37567767

RESUMEN

AIMS: Knowledge about adverse drug events caused by drug-drug interactions (DDI-ADEs) is limited. We aimed to provide detailed insights about DDI-ADEs related to three frequent, high-risk potential DDIs (pDDIs) in the critical care setting: pDDIs with international normalized ratio increase (INR+ ) potential, pDDIs with acute kidney injury (AKI) potential, and pDDIs with QTc prolongation potential. METHODS: We extracted routinely collected retrospective data from electronic health records of intensive care units (ICUs) patients (≥18 years), admitted to ten hospitals in the Netherlands between January 2010 and September 2019. We used computerized triggers (e-triggers) to preselect patients with potential DDI-ADEs. Between September 2020 and October 2021, clinical experts conducted a retrospective manual patient chart review on a subset of preselected patients, and assessed causality, severity, preventability, and contribution to ICU length of stay of DDI-ADEs using internationally prevailing standards. RESULTS: In total 85 422 patients with ≥1 pDDI were included. Of these patients, 32 820 (38.4%) have been exposed to one of the three pDDIs. In the exposed group, 1141 (3.5%) patients were preselected using e-triggers. Of 237 patients (21%) assessed, 155 (65.4%) experienced an actual DDI-ADE; 52.9% had severity level of serious or higher, 75.5% were preventable, and 19.3% contributed to a longer ICU length of stay. The positive predictive value was the highest for DDI-INR+ e-trigger (0.76), followed by DDI-AKI e-trigger (0.57). CONCLUSION: The highly preventable nature and severity of DDI-ADEs, calls for action to optimize ICU patient safety. Use of e-triggers proved to be a promising preselection strategy.


Asunto(s)
Lesión Renal Aguda , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Humanos , Estudios Retrospectivos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/etiología , Interacciones Farmacológicas , Unidades de Cuidados Intensivos , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/epidemiología
2.
J Magn Reson Imaging ; 46(2): 497-504, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28130811

RESUMEN

PURPOSE: To evaluate whether brown adipose tissue (BAT) is present in middle-aged patients with cardiovascular comorbidities and to quantify how BAT presence associates with obesity and metabolic dysfunction. MATERIALS AND METHODS: Supraclavicular and subcutaneous adipose tissue fat-signal-fraction (FF) was determined with 1.5T water-fat magnetic resonance imaging (MRI) in 50 patients with coronary artery disease, cerebrovascular disease, or peripheral artery disease. The association between BAT presence, as measured by a higher FF difference between supraclavicular and subcutaneous adipose tissue, and obesity and metabolic dysfunction was quantified using multivariable linear regression. RESULTS: Supraclavicular adipose tissue displays a lower FF of 82.6% (interquartile range [IQR] 78.8-84.3) compared to 90.2% (IQR 87.3-91.9) in subcutaneous white adipose tissue (WAT, P < 0.0001). BAT presence was associated with less obesity and metabolic dysfunction. For example, 1 SD lower waist circumference (11.7 cm), 1 SD lower triglycerides (1.0 mmol/L), and absence of metabolic syndrome and type 2 diabetes were associated with 1.1% (95% confidence interval [CI] 0.1; 2.0), 1.1% (95% CI 0.1; 2.0), 2.1% (95% CI 0.1; 4.1), and 4.1% (95% CI 0.1; 7.1) higher FF difference between supraclavicular adipose tissue and subcutaneous WAT, respectively. CONCLUSION: Supraclavicular adipose tissue has BAT characteristics in adult patients with clinical manifest cardiovascular disease and BAT presence is associated with less obesity and a more favorable metabolic profile. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:497-504.


Asunto(s)
Tejido Adiposo Pardo/diagnóstico por imagen , Enfermedades Cardiovasculares/diagnóstico por imagen , Diabetes Mellitus Tipo 2/diagnóstico por imagen , Imagen por Resonancia Magnética , Tejido Adiposo/diagnóstico por imagen , Tejido Adiposo Blanco/diagnóstico por imagen , Anciano , Enfermedades Cardiovasculares/complicaciones , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Complicaciones de la Diabetes/diagnóstico por imagen , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/diagnóstico por imagen , Obesidad/metabolismo , Enfermedad Arterial Periférica/diagnóstico por imagen , Estudios Prospectivos , Factores de Riesgo , Grasa Subcutánea
3.
NMR Biomed ; 29(1): 48-56, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26620447

RESUMEN

The supraclavicular fat depot is known for brown adipose tissue presence. To unravel adipose tissue physiology and metabolism, high quality and reproducible imaging is required. In this study we quantified the reliability and agreement of MRI fat fraction measurements in supraclavicular and subcutaneous adipose tissue of 25 adult patients with clinically manifest cardiovascular disease. MRI fat fraction measurements were made under ambient temperature conditions using a vendor supplied mDixon chemical-shift water-fat multi-echo pulse sequence at 1.5 T field strength. Supraclavicular fat fraction reliability (intraclass correlation coefficientagreement , ICCagreement ) was 0.97 for test-retest, 0.95 for intra-observer and 0.56 for inter-observer measurements, which increased to 0.88 when ICCconsistency was estimated. Supraclavicular fat fraction agreement displayed mean differences of 0.5% (limit of agreement (LoA) -1.7 to 2.6) for test-retest, -0.5% (LoA -2.9 to 2.0) for intra-observer and 5.6% (LoA 0.4 to 10.8) for inter-observer measurements. Median fat fraction in supraclavicular adipose tissue was 82.5% (interquartile range (IQR) 78.6-84.0) and 89.7% (IQR 87.2-91.5) in subcutaneous adipose tissue (p < 0.0001). In conclusion, water-fat MRI has good reliability and agreement to measure adipose tissue fat fraction in patients with manifest cardiovascular disease. These findings enable research on determinants of fat fraction and enable longitudinal monitoring of fat fraction within adipose tissue depots. Interestingly, even in adult patients with manifest cardiovascular disease, supraclavicular adipose tissue has a lower fat fraction compared with subcutaneous adipose tissue, suggestive of distinct morphologic characteristics, such as brown adipose tissue.


Asunto(s)
Tejido Adiposo/metabolismo , Enfermedades Cardiovasculares/metabolismo , Imagen por Resonancia Magnética/métodos , Anciano , Enfermedades Cardiovasculares/patología , Humanos , Persona de Mediana Edad , Reproducibilidad de los Resultados
4.
Ann Surg ; 262(2): 304-11, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25915914

RESUMEN

OBJECTIVE: Aim of this study was to draw comparisons between human colonic and jejunal ischemia-reperfusion sequelae in a human in vivo experimental model. BACKGROUND: In patients, colonic ischemia-reperfusion generally has a milder course than small intestinal ischemia-reperfusion. It is unclear which pathophysiologic processes are responsible for this difference. METHODS: In 10 patients undergoing colonic surgery and 10 patients undergoing pancreaticoduodenectomy, 6 cm colon or jejunum was isolated and exposed to 60 minutes ischemia followed by various reperfusion periods. Morphology (hematoxylin and eosin), apoptosis (M30), tight junctions (zonula occludens 1), and neutrophil influx (myeloperoxidase) were assessed using immunohistochemistry. Quantitative polymerase chain reaction and enzyme-linked immunosorbent assay were performed for interleukin-6 and tumor necrosis factor-α. RESULTS: Hematoxylin and eosin staining revealed intact colonic epithelial lining, but extensive damage in jejunal villus tips after 60 minutes ischemia. After reperfusion, the colonic epithelial lining was not affected, whereas the jejunal epithelium was seriously damaged. Colonic apoptosis was limited to scattered cells in surface epithelium, whereas apoptosis was clearly observed in jejunal villi and crypts, (42 times more M30 positivity compared with colon, P < 0.01). Neutrophil influx and increased tumor necrosis factor-α mRNA expression were observed in jejunum after 30 and 120 minutes of reperfusion (P < 0.05). Interleukin-6 mRNA expression was increased in jejunum after 120 minutes of reperfusion (3.6-fold increase, P < 0.05), whereas interleukin-6 protein expression was increased in both colon (1.5-fold increase, P < 0.05) and small intestine (1.5-fold increase, P < 0.05) after 30 and 120 minutes of reperfusion. CONCLUSIONS: Human colon is less susceptible to IR-induced tissue injury than small intestine.


Asunto(s)
Colectomía/efectos adversos , Colon/irrigación sanguínea , Yeyuno/irrigación sanguínea , Pancreaticoduodenectomía/efectos adversos , Daño por Reperfusión/etiología , Daño por Reperfusión/patología , Colon/metabolismo , Colon/patología , Disección , Humanos , Interleucina-6/metabolismo , Yeyuno/metabolismo , Yeyuno/patología , Neoplasias Pancreáticas/cirugía , Neoplasias del Recto/cirugía , Daño por Reperfusión/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
5.
Rev Esp Cir Ortop Traumatol ; 68(2): T159-T167, 2024.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38000543

RESUMEN

OBJECTIVE: To determine, through a systematic review, the effects of halo-gravity traction (HGT) in spinal deformity. METHODS: Prospective studies or case series of patients with scoliosis or kyphosis treated with cranial HGT were included. Radiological outcomes were measured in the sagittal and/or coronal planes. Pulmonary function was also assessed. Perioperative complications were also collected. RESULTS: Thirteen studies were included. Congenital etiology was the most frequent etiology observed. Most studies provided clinically relevant curve correction values in the sagittal and coronal planes. Pulmonary values improved significantly after the use of HGT. Finally, there were a pool of 83 complications in 356 patients (23.3%). The most frequent complications were screw infection (38 cases). CONCLUSIONS: Preoperative HGT appears to be a safe and effective intervention for deformity that allows correction prior to surgery. However, there is a lack of homogeneity in the published studies.

6.
Rev Esp Cir Ortop Traumatol ; 68(2): 159-167, 2024.
Artículo en Inglés, Español | MEDLINE | ID: mdl-37230411

RESUMEN

OBJECTIVE: To determine, through a systematic review, the effects of halo gravity traction in spinal deformity. METHODS: Prospective studies or case series of patients with scoliosis or kyphosis treated with cranial halo gravity traction (HGT) were included. Radiological outcomes were measured in the sagittal and/or coronal planes. Pulmonary function was also assessed. Perioperative complications were also collected. RESULTS: Thirteen studies were included. Congenital etiology was the most frequent etiology observed. Most studies provided clinically relevant curve correction values in the sagittal and coronal planes. Pulmonary values improved significantly after the use of HGT. Finally, there were a pool of 83 complications in 356 patients (23.3%). The most frequent complications were screw infection (38 cases). CONCLUSIONS: Preoperative HGT appears to be a safe and effective intervention for deformity that allows correction prior to surgery. However, there is a lack of homogeneity in the published studies.

7.
ACS Appl Energy Mater ; 7(14): 5869-5878, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39055068

RESUMEN

In p-i-n perovskite solar cells optical excitation of defect states at the interface between the perovskite and fullerene electron transport layer (ETL) creates a photocurrent responsible for a distinct sub-bandgap external quantum efficiency (EQE). The precise nature of these signals and their impact on cell performance are largely unknown. Here, the effect of n-doping the fullerene on the EQE spectra is studied. The n-doped fullerene is either deposited from solution or by coevaporation. The latter method is used to create undoped-doped fullerene bilayers and investigate the effect of the proximity of the doped region on the EQE spectra. The intensity of the sub-bandgap EQE increases when the ETL is n-doped and also when the device is biased with green light. Using these results, the sub-bandgap EQE signal is attributed to originate from electron trap states in the perovskite with an energy below the conduction band that are filled by excitation with low-energy photons. The trapped electrons give rise to photocurrent when they are collected at a nearby electrode. The enhanced sub-bandgap EQE observed when the ETL is n-doped or bias light is applied, is related to a higher probability to extract trapped electrons under these conditions.

8.
Rev Esp Cir Ortop Traumatol ; 67(6): S552-S559, 2023.
Artículo en Inglés, Español | MEDLINE | ID: mdl-37774915

RESUMEN

We described an algorithm for the management of spinal metastases in which the importance of single parameters varies depending on when they are contemplated. Each patient follows his own «personal¼ sequential process which does not necessarily consider all the parameters each time as some may be irrelevant for the purpose of choosing the type of treatment for that single individual. For instance, a patient in general poor condition with a high ASA score is usually not a candidate for surgery, regardless of the primary tumor nature or the number of metastases. For this patient, the most important element would be the sensitivity of the tumor to adjuvant treatment. Similarly, a patient with acute and progressive spinal cord injury would undergo surgical decompression and stabilization without considering a more strenuous intervention.

9.
Rev Esp Cir Ortop Traumatol ; 67(6): 552-559, 2023.
Artículo en Inglés, Español | MEDLINE | ID: mdl-37343934

RESUMEN

We described an algorithm for the management of spinal metastases in which the importance of single parameters varies depending on when they are contemplated. Each patient follows his own "personal" sequential process which does not necessarily consider all the parameters each time as some may be irrelevant for the purpose of choosing the type of treatment for that single individual. For instance, a patient in general poor condition with a high "ASA" score is usually not a candidate for surgery, regardless of the primary tumor nature or the number of metastases. For this patient, the most important element would be the sensitivity of the tumor to adjuvant treatment. Similarly, a patient with acute and progressive spinal cord injury would undergo surgical decompression and stabilization without considering a more strenuous intervention.

10.
Adv Mater ; 35(8): e2209598, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36482790

RESUMEN

Organic bulk heterojunction photodiodes (OPDs) attract attention for sensing and imaging. Their detectivity is typically limited by a substantial reverse bias dark current density (Jd ). Recently, using thermal admittance or spectral photocurrent measurements, Jd has been attributed to thermal charge generation mediated by mid-gap states. Here, the temperature dependence of Jd in state-of-the-art OPDs is reported with Jd down to 10-9  mA cm-2 at -0.5 V bias. For a variety of donor-acceptor bulk-heterojunction blends it is found that the thermal activation energy of Jd is lower than the effective bandgap of the blends, by ca. 0.3 to 0.5 eV, but higher than expected for mid-gap states. Ultra-sensitive sub-bandgap photocurrent spectroscopy reveals that the minimum photon energy for optical charge generation in OPDs correlates with the dark current thermal activation energy. The dark current in OPDs is attributed to thermal charge generation at the donor-acceptor interface mediated by intra-gap states near the band edges.

11.
Clin Exp Metastasis ; 40(3): 243-253, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37211565

RESUMEN

Patients with peritoneal metastases (PM) of colorectal cancer have a very poor outcome. Intraperitoneal delivery of chemotherapy is the preferred route for PM treatment. The main limitation of the treatment options is the short residence time of the cytostatic, with subsequent short exposure of the cancer cells. To address this, a supramolecular hydrogel has been developed that allows both local and slow release of its encapsulated drug, mitomycin C (MMC) or cholesterol-conjugated MMC (cMMC), respectively. This experimental study investigates if drug delivery using this hydrogel improves the therapeutic efficacy against PM. PM was induced in WAG/Rij rats (n = 72) by intraperitoneally injecting syngeneic colon carcinoma cells (CC531) expressing luciferase. After seven days, animals received a single intraperitoneal injection with saline (n = 8), unloaded hydrogel (n = 12), free MMC (n = 13), free cMMC (n = 13), MMC-loaded hydrogel (n = 13), or cMMC-loaded hydrogel (n = 13). Primary outcome was overall survival with a maximum follow-up of 120 days. Intraperitoneal tumor development was non-invasive monitored via bioluminescence imaging. Sixty-one rats successfully underwent all study procedures and were included to assess therapeutic efficacy. After 120 days, the overall survival in the MMC-loaded hydrogel and free MMC group was 78% and 38%, respectively. A trend toward significance was found when comparing the survival curves of the MMC-loaded hydrogel and free MMC (p = 0.087). No survival benefit was found for the cMMC-loaded hydrogel compared to free cMMC. Treating PM with our MMC-loaded hydrogel, exhibiting prolonged MMC exposure, seems effective in improving survival compared to treatment with free MMC.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Citostáticos , Neoplasias Peritoneales , Ratas , Animales , Citostáticos/uso terapéutico , Neoplasias Peritoneales/secundario , Hidrogeles/uso terapéutico , Roedores , Mitomicina , Neoplasias del Colon/tratamiento farmacológico , Neoplasias Colorrectales/tratamiento farmacológico
12.
ACS Appl Energy Mater ; 6(7): 3933-3943, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37064411

RESUMEN

2H-Benzotriazol-2-ylethylammonium bromide and iodide and its difluorinated derivatives are synthesized and employed as interlayers for passivation of formamidinium lead triiodide (FAPbI3) solar cells. In combination with PbI2 and PbBr2, these benzotriazole derivatives form two-dimensional (2D) Ruddlesden-Popper perovskites (RPPs) as evidenced by their crystal structures and thin film characteristics. When used to passivate n-i-p FAPbI3 solar cells, the power conversion efficiency improves from 20% to close to 22% by enhancing the open-circuit voltage. Quasi-Fermi level splitting experiments and scanning electron microscopy cathodoluminescence hyperspectral imaging reveal that passivation provides a reduced nonradiative recombination at the interface between the perovskite and hole transport layer. Photoluminescence spectroscopy, angle-resolved grazing-incidence wide-angle X-ray scattering, and depth profiling X-ray photoelectron spectroscopy studies of the 2D/three-dimensional (3D) interface between the benzotriazole RPP and FAPbI3 show that a nonuniform layer of 2D perovskites is enough to passivate defects, enhance charge extraction, and decrease nonradiative recombination.

13.
ACS Appl Energy Mater ; 6(10): 5217-5229, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37234970

RESUMEN

Monolithic perovskite/c-Si tandem solar cells have attracted enormous research attention and have achieved efficiencies above 30%. This work describes the development of monolithic tandem solar cells based on silicon heterojunction (SHJ) bottom- and perovskite top-cells and highlights light management techniques assisted by optical simulation. We first engineered (i)a-Si:H passivating layers for (100)-oriented flat c-Si surfaces and combined them with various (n)a-Si:H, (n)nc-Si:H, and (n)nc-SiOx:H interfacial layers for SHJ bottom-cells. In a symmetrical configuration, a long minority carrier lifetime of 16.9 ms was achieved when combining (i)a-Si:H bilayers with (n)nc-Si:H (extracted at the minority carrier density of 1015 cm-3). The perovskite sub-cell uses a photostable mixed-halide composition and surface passivation strategies to minimize energetic losses at charge-transport interfaces. This allows tandem efficiencies above 23% (a maximum of 24.6%) to be achieved using all three types of (n)-layers. Observations from experimentally prepared devices and optical simulations indicate that both (n)nc-SiOx:H and (n)nc-Si:H are promising for use in high-efficiency tandem solar cells. This is possible due to minimized reflection at the interfaces between the perovskite and SHJ sub-cells by optimized interference effects, demonstrating the applicability of such light management techniques to various tandem structures.

14.
Theriogenology ; 181: 113-118, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35078123

RESUMEN

The objective of the present study was to evaluate the biomarkers specific to lung endothelial and epithelial damage in the determination of lung injury and its severity in calves with perinatal asphyxia and to evaluate their prognostic importance among survivors and non-survivor calves. Ten healthy calves and 20 calves with perinatal asphyxia were enrolled in the study. Clinical examination and laboratory analysis were performed at admission. Serum concentrations of soluble advanced glycation end-product receptor (sRAGE), soluble E-selectin (sE-selectin), clara cell secretory protein (CC16), and soluble intercellular adhesion molecule-1 (sICAM-1) were measured to assess lung injury. Venous pH, sO2, HCO3, and BE of calves with perinatal asphyxia were significantly lower than the healthy calves. sRAGE, sE-selectin, pCO2, and lactate were significantly high in calves with asphyxia. ROC analysis showed that sRAGE, sE-selectin, pCO2, lactate, and respiratory rate were higher while HCO3 and BE were lower in the nonsurvivor calves than survivors. In conclusion, serum sRAGE and sE-selectin concentrations highlight the utility of these biomarkers in determining lung injury in calves with asphyxia. Also, pH, pCO2, lactate, HCO3, BE, and respiratory rate along with serum sRAGE and sE-selectin were useful indicators in the prediction of mortality.


Asunto(s)
Enfermedades de los Bovinos , Lesión Pulmonar , Animales , Asfixia/veterinaria , Biomarcadores , Bovinos , Productos Finales de Glicación Avanzada , Lesión Pulmonar/veterinaria , Selectinas
15.
Ned Tijdschr Geneeskd ; 1662022 12 06.
Artículo en Holandés | MEDLINE | ID: mdl-36633083

RESUMEN

Currently, the meaning of the I-category of the antibiogram in culture results is changing in The Netherlands. Before, the I-category was called 'intermediate' and included combinations of antibiotics and micro-organisms in which the chance of therapeutic success was doubtful. Therefore, in clinical practice this category was mostly avoided and considered as 'in this case not clear'. From now on, the definition of I has changed to 'susceptible, increased exposure' and can be considered as a valid treatment option when adequate (higher) dosing is applied. Because of the large-scale implementation, not all microbiological laboratories may be able to implement the new I at the same moment and the way they may execute this may differ in detail. When considering treating a patient with 'susceptible, increased exposure' and you are in doubt whether your microbiological laboratory already has implemented the new definition of I or about the correct dosage, consult your clinical microbiologist or Antimicrobial Stewardship Team.


Asunto(s)
Antibacterianos , Emociones , Humanos , Antibacterianos/uso terapéutico , Pruebas de Sensibilidad Microbiana , Países Bajos
16.
Nat Commun ; 13(1): 349, 2022 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-35039493

RESUMEN

Defects in perovskite solar cells are known to affect the performance, but their precise nature, location, and role remain to be firmly established. Here, we present highly sensitive measurements of the sub-bandgap photocurrent to investigate defect states in perovskite solar cells. At least two defect states can be identified in p-i-n perovskite solar cells that employ a polytriarylamine hole transport layer and a fullerene electron transport layer. By comparing devices with opaque and semi-transparent back contacts, we demonstrate the large effect of optical interference on the magnitude and peak position in the sub-bandgap external quantum efficiency (EQE) in perovskite solar cells. Optical simulations reveal that defects localized near the interfaces are responsible for the measured photocurrents. Using optical spacers of different lengths and a mirror on top of a semi-transparent device, allows for the precise manipulation of the optical interference. By comparing experimental and simulated EQE spectra, we show that sub-bandgap defects in p-i-n devices are located near the perovskite-fullerene interface.

17.
ACS Appl Energy Mater ; 4(7): 6650-6658, 2021 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-34337343

RESUMEN

Light-induced halide segregation hampers obtaining stable wide-band-gap solar cells based on mixed iodide-bromide perovskites. So far, the effect of prolonged illumination on the performance of mixed-halide perovskite solar cells has not been studied in detail. It is often assumed that halide segregation leads to a loss of open-circuit voltage. By simultaneously recording changes in photoluminescence and solar cell performance under prolonged illumination, we demonstrate that cells instead deteriorate by a loss of short-circuit current density and that the open-circuit voltage is less affected. The concurrent red shift, increased lifetime, and higher quantum yield of photoluminescence point to the formation of relatively emissive iodide-rich domains under illumination. Kinetic Monte Carlo simulations provide an atomistic insight into their formation via exchange of bromide and iodide, mediated by halide vacancies. Localization of photogenerated charge carriers in low-energy iodide-rich domains and subsequent recombination cause reduced photocurrent and red-shifted photoluminescence. The loss in photovoltaic performance is diminished by partially replacing organic cations by cesium ions. Ultrasensitive photocurrent spectroscopy shows that cesium ions result in a lower density of sub-band-gap defects and suppress defect growth under illumination. These defects are expected to play a role in the development and recovery of light-induced compositional changes.

18.
Nat Commun ; 12(1): 7277, 2021 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-34907190

RESUMEN

Metal halide perovskite photodiodes (PPDs) offer high responsivity and broad spectral sensitivity, making them attractive for low-cost visible and near-infrared sensing. A significant challenge in achieving high detectivity in PPDs is lowering the dark current density (JD) and noise current (in). This is commonly accomplished using charge-blocking layers to reduce charge injection. By analyzing the temperature dependence of JD for lead-tin based PPDs with different bandgaps and electron-blocking layers (EBL), we demonstrate that while EBLs eliminate electron injection, they facilitate undesired thermal charge generation at the EBL-perovskite interface. The interfacial energy offset between the EBL and the perovskite determines the magnitude and activation energy of JD. By increasing this offset we realized a PPD with ultralow JD and in of 5 × 10-8 mA cm-2 and 2 × 10-14 A Hz-1/2, respectively, and wavelength sensitivity up to 1050 nm, establishing a new design principle to maximize detectivity in perovskite photodiodes.

19.
JACC Case Rep ; 3(14): 1589-1593, 2021 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34729507

RESUMEN

This report describes the case of a symptomatic patient with a right coronary artery fistula draining into the coronary sinus who underwent transcatheter closure, which was deployed in the drainage site to seal off the exit of the fistula. (Level of Difficulty: Advanced.).

20.
J Phys Chem C Nanomater Interfaces ; 125(10): 5505-5517, 2021 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-33828634

RESUMEN

The combination of narrow-bandgap diketopyrrolopyrrole (DPP) polymers and nonfullerene acceptors (NFAs) seems well-matched for solar cells that exclusively absorb in the near infrared but they rarely provide high efficiency. One reason is that processing of the active layer is complicated by the fact that DPP-based polymers are generally only sufficiently soluble in chloroform (CF), while NFAs are preferably processed from halogenated aromatic solvents. By using a ternary solvent system consisting of CF, 1,8-diiodooctane (DIO), and chlorobenzene (CB), the short-circuit current density is increased by 50% in solar cells based on a DPP polymer (PDPP5T) and a NFA (IEICO-4F) compared to the use of CF with DIO only. However, the open-circuit voltage and fill factor are reduced. As a result, the efficiency improves from 3.4 to 4.8% only. The use of CB results in stronger aggregation of IEICO-4F as inferred from two-dimensional grazing-incidence wide-angle X-ray diffraction. Photo- and electroluminescence and mobility measurements indicate that the changes in performance can be ascribed to a more aggregated blend film in which charge generation is increased but nonradiative recombination is enhanced because of reduced hole mobility. Hence, while CB is essential to obtain well-ordered domains of IEICO-4F in blends with PDPP5T, the morphology and resulting hole mobility of PDPP5T domains remain suboptimal. The results identify the challenges in processing organic solar cells based on DPP polymers and NFAs as near-infrared absorbing photoactive layers.

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