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1.
J Virol ; 98(5): e0151623, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38567951

RESUMEN

The non-human primate (NHP) model (specifically rhesus and cynomolgus macaques) has facilitated our understanding of the pathogenic mechanisms of yellow fever (YF) disease and allowed the evaluation of the safety and efficacy of YF-17D vaccines. However, the accuracy of this model in mimicking vaccine-induced immunity in humans remains to be fully determined. We used a systems biology approach to compare hematological, biochemical, transcriptomic, and innate and antibody-mediated immune responses in cynomolgus macaques and human participants following YF-17D vaccination. Immune response progression in cynomolgus macaques followed a similar course as in adult humans but with a slightly earlier onset. Yellow fever virus neutralizing antibody responses occurred earlier in cynomolgus macaques [by Day 7[(D7)], but titers > 10 were reached in both species by D14 post-vaccination and were not significantly different by D28 [plaque reduction neutralization assay (PRNT)50 titers 3.6 Log vs 3.5 Log in cynomolgus macaques and human participants, respectively; P = 0.821]. Changes in neutrophils, NK cells, monocytes, and T- and B-cell frequencies were higher in cynomolgus macaques and persisted for 4 weeks versus less than 2 weeks in humans. Low levels of systemic inflammatory cytokines (IL-1RA, IL-8, MIP-1α, IP-10, MCP-1, or VEGF) were detected in either or both species but with no or only slight changes versus baseline. Similar changes in gene expression profiles were elicited in both species. These included enriched and up-regulated type I IFN-associated viral sensing, antiviral innate response, and dendritic cell activation pathways D3-D7 post-vaccination in both species. Hematological and blood biochemical parameters remained relatively unchanged versus baseline in both species. Low-level YF-17D viremia (RNAemia) was transiently detected in some cynomolgus macaques [28% (5/18)] but generally absent in humans [except one participant (5%; 1/20)].IMPORTANCECynomolgus macaques were confirmed as a valid surrogate model for replicating YF-17D vaccine-induced responses in humans and suggest a key role for type I IFN.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Macaca fascicularis , Vacuna contra la Fiebre Amarilla , Fiebre Amarilla , Virus de la Fiebre Amarilla , Animales , Vacuna contra la Fiebre Amarilla/inmunología , Humanos , Fiebre Amarilla/prevención & control , Fiebre Amarilla/inmunología , Fiebre Amarilla/virología , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Virus de la Fiebre Amarilla/inmunología , Vacunación , Masculino , Femenino , Modelos Animales de Enfermedad , Adulto , Inmunidad Innata , Biología de Sistemas/métodos
2.
ACS Appl Mater Interfaces ; 16(9): 11516-11527, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38391145

RESUMEN

High-quality Cu2(Zn,Fe,Cd)SnS4 (CZFCTS) thin films based on the parent CZTS were prepared by aerosol-assisted chemical vapor deposition (AACVD). Substitution of Zn by Fe and Cd significantly improved the electrical transport properties, and monophasic CZFCTS thin films exhibited a maximum power factor (PF) of ∼0.22 µW cm-1 K-2 at 575 K. The quality and performance of the CZFCTS thin films were further improved by postdeposition annealing. CZFCTS thin films annealed for 24 h showed a significantly enhanced maximum PF of ∼2.4 µW cm-1 K-2 at 575 K. This is higher than all reported values for single-phase quaternary sulfide (Cu2BSnS4, B = Mn, Fe, Co, Ni) thin films and even exceeds the PF for most polycrystalline bulk materials of these sulfides. Density functional theory (DFT) calculations were performed to understand the impact of Cd and Fe substitution on the electronic properties of CZTS. It was predicted that CZFCTS would have a smaller band gap than CZTS and a higher density of states (DoS) near the Fermi level. The thermal conductivity and thermoelectric figure of merit (zT) of the CZFCTS thin films have been evaluated, yielding an estimated maximum zT range of 0.18-0.69 at 550 K. The simple processing route and improved thermoelectric performance make CZFCTS thin films extremely promising for thermoelectric energy generation.

3.
J Surg Case Rep ; 2024(2): rjae035, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38333561

RESUMEN

Colouterine fistula is a rare but recognizable complication of diverticulitis. This case illustrates the presence of a colouterine fistula in an elderly patient who had an atypical presentation for diverticulitis. She was initially treated with intravenous antibiotics for diverticulitis with a contained abscess. This gave her an opportunity to avoid surgery. However, her sepsis failed to respond to the initial treatment. Progress computerized tomography imaging demonstrated the presence of a colouterine fistula for which she required source control. Thus she underwent laparotomy, Hartmann's procedure, and total abdominal hysterectomy with bilateral salpingo-oophorectomy. The diagnosis of colouterine fistula was confirmed intraoperatively and on histopathology. Subsequently, the patient had an uneventful recovery following the operation. This case highlights the rarity but also the veracity of this clinical entity.

4.
Drug Saf ; 47(3): 261-270, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38183608

RESUMEN

BACKGROUND: To assess the causal relationship between a medicinal product and a reported event, relevant information needs to be present. Information elements for assessing cases of exposure to medicinal products during pregnancy were predefined and used in a new tool to assess the quality of information. However, the extent in which the presence or absence of these predefined information elements is associated with the overall clinical quality of these cases, as evaluated by pharmacovigilance experts, remains uncertain. OBJECTIVE: We aimed to validate a novel method to assess the clinical quality of information in real-world pregnancy pharmacovigilance case reports. METHODS: The clinical quality of case reports regarding medicinal product exposure and pregnancy-related outcomes was appraised from spontaneous reports, literature, Teratology Information Services (UK and Switzerland), The Dutch Pregnancy Drug Register, the Gilenya pregnancy registry and the Enhanced PV programme of Novartis. Assessment was done by means of the novel standardised tool based on the presence and relevance of information, and by expert judgement. The novel tool was validated compared to the expert assessment as the gold standard expressed as the area under the receiver operating characteristic curves, after which the sensitivity and specificity were calculated using cross-tabulations. Inter-rater variability was determined by means of weighted Cohen's kappa. RESULTS: One hundred and eighty-six case reports were included. The clinical quality score as assessed by the novel method was divided into three categories with cut-off values of 45% (poor to intermediate) and 65% (intermediate to excellent). Sensitivity was 0.93 and 0.96 for poor to intermediate and intermediate to excellent, respectively. Specificity was respectively 0.52 and 0.73. Inter-rater variability was 0.65 (95% confidence interval 0.53-0.78) for the newly developed approach, and 0.40 (95% confidence interval 0.28-0.52) for the gold standard assessment. CONCLUSIONS: The tool described in this study using the presence and relevance of elements of information is the first designed, validated and standardised method for the assessment of the quality of information of case reports in pregnancy pharmacovigilance data. This method confers less inter-rater variability compared with a quality assessment by experts of pregnancy-related pharmacovigilance data.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Humanos , Embarazo , Femenino , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Farmacovigilancia , Sistemas de Registro de Reacción Adversa a Medicamentos , Causalidad , Juicio
5.
Chem Mater ; 35(19): 7904-7914, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37840778

RESUMEN

High entropy metal chalcogenides are materials containing five or more elements within a disordered sublattice. These materials exploit a high configurational entropy to stabilize their crystal structure and have recently become an area of significant interest for renewable energy applications such as electrocatalysis and thermoelectrics. Herein, we report the synthesis of bulk particulate HE zinc sulfide analogues containing four, five, and seven metals. This was achieved using a molecular precursor cocktail approach with both transition and main group metal dithiocarbamate complexes which are decomposed simultaneously in a rapid (1 h) and low-temperature (500 °C) thermolysis reaction to yield high entropy and entropy-stabilized metal sulfides. The resulting materials were characterized by powder XRD, SEM, and TEM, alongside EDX spectroscopy at both the micro- and nano-scales. The entropy-stabilized (CuAgZnCoMnInGa)S material was demonstrated to be an excellent electrocatalyst for the hydrogen evolution reaction when combined with conducting carbon black, achieving a low onset overpotential of (∼80 mV) and η10 of (∼255 mV).

6.
Chem Commun (Camb) ; 59(83): 12427-12430, 2023 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-37782088

RESUMEN

Herein we report for the first time the synthesis of a high entropy (CuZnCoInGa)S metal sulfide thin film deposited by AACVD using molecular precursors.

7.
Cryst Growth Des ; 23(10): 6998-7009, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37808901

RESUMEN

High-entropy materials are a nascent class of materials that exploit a high configurational entropy to stabilize multiple elements in a single crystal lattice and to yield unique physical properties for applications in energy storage, catalysis, and thermoelectric energy conversion. Initially, the synthesis of these materials was conducted by approaches requiring high temperatures and long synthetic time scales. However, successful homogeneous mixing of elements at the atomic level within the lattice remains challenging, especially for the synthesis of nanomaterials. The use of atom-up synthetic approaches to build crystal lattices atom by atom, rather than the top-down alteration of extant crystalline lattices, could lead to faster, lower-temperature, and more sustainable approaches to obtaining high entropy materials. In this Perspective, we discuss some of these state-of-the-art atom-up synthetic approaches to high entropy materials and contrast them with more traditional approaches.

8.
Pharmaceut Med ; 37(6): 439-449, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37594662

RESUMEN

There is considerable societal interest in making medicines more affordable. A critical factor often inadequately considered early in the process of adding drugs to a company's product portfolio is that some products may require additional monitoring and complex, demanding and expensive additional risk minimisation measures (aRMMs). These aRMMs may have a sizeable impact on a company's commitment to that medicinal product throughout the product's entire life cycle. The teratogenic phthalimides were selected as an example of medicines that are recently being genericised and require a substantial commitment in terms of additional monitoring and aRMMs, most notably in the form of pregnancy prevention programmes (PPPs) with controlled distribution systems (CDSs). Implementing PPPs with CDSs is complex and demanding and encompasses all routine activities, aRMMs, local/regional Health Authority (HA) requirements, and commercialisation strategies. Considerations have been summarised that can support decision-making during due diligence processes, implementation and monitoring. Proactive, effective pharmacovigilance requires innovative, sustainable and flexible solutions to maintain high standards across the board. In particular, generic marketing authorisation holders operate with limited resources and may benefit appreciably from the following proposed suggestions and solutions such as early planning and preparation, knowledge-sharing, utilisation of new technologies and implementation of measures beyond HA-mandated requirements.


Asunto(s)
Farmacovigilancia , Teratógenos , Embarazo , Femenino , Humanos , Teratógenos/toxicidad
9.
Ther Innov Regul Sci ; 57(5): 1017-1029, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37270450

RESUMEN

The pharmacovigilance agreements (PVA) landscape has evolved over recent decades with rapid growth in the number and complexity of partnerships, mergers, and acquisitions between pharmaceutical companies. Simultaneously there has been increasing scrutiny from regulatory authorities. Detailed regulations and guidance are lacking in this domain; hence companies have developed their own processes, templates, and tools, which have headed in different directions. Where feasible, marketing authorization holders (MAHs) have written contracts based on mutually understood requirements. Currently, MAHs are striving to find optimal solutions that safeguard patients, and in turn, support pharmacovigilance compliance. Through the TransCelerate BioPharma consortium MAHs are seeking simplification and efficiencies, to optimize the process of developing contractual agreements for pharmacovigilance. A survey of MAHs confirmed the perceptions above, and the need for efficient solutions to help navigate through the maze of complexity. The authors have led the development of tools and techniques to enable partnership between MAHs, and ultimately to support patient safety.


Asunto(s)
Negociación , Farmacovigilancia , Humanos , Seguridad del Paciente
10.
ACS Appl Energy Mater ; 6(8): 4462-4474, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-37123105

RESUMEN

Orthorhombic SnS exhibits excellent thermoelectric performance as a consequence its relatively high Seebeck coefficient and low thermal conductivity. In the present work, polycrystalline orthorhombic SnS thin films were prepared by aerosol-assisted chemical vapor deposition (AACVD) using the single source precursor dibutyl-bis(diethyldithiocarbamato)tin(IV) [Sn(C4H9)2(S2CN(C2H5)2)2]. We examined the effects of the processing parameters on the composition, microstructure, and electrical transport properties of the SnS films. Deposition temperature dominates charge transport; the room temperature electrical conductivity increased from 0.003 to 0.19 S·cm-1 as deposition temperature increased from 375 to 445 °C. Similarly, the maximum power factor (PF) increased with deposition temperature, reaching ∼0.22 µW·cm-1·K-2 at 570 K. The power factors for SnS films deposited by AACVD are higher than values from earlier work on SnS bulks and SnS/SnSe films at temperatures up to 520 K. The electronic structure and electrical transport properties of SnS were investigated using density-functional theory to provide an improved understanding of the materials performance. To the best of our knowledge, the thermal conductivity (κ) of SnS film was measured for the first time allowing the figure of merit (zT) for SnS film to be evaluated. A relatively low thermal conductivity of ∼0.41 W·m-1·K-1 was obtained at 550 K for SnS films deposited at 445 °C; the corresponding zT value was ∼0.026. The SnS films are good candidates for thermoelectric applications and AACVD is a promising technique for the preparation of high-performance thermoelectric films.

12.
Drug Saf ; 46(5): 479-491, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36976447

RESUMEN

INTRODUCTION AND OBJECTIVE: The risks and benefits of medication use in pregnancy are typically established through post-marketing observational studies. As there is currently no standardised or systematic approach to the post-marketing assessment of medication safety in pregnancy, data generated through pregnancy pharmacovigilance (PregPV) research can be heterogenous and difficult to interpret. The aim of this article is to describe the development of a reference framework of core data elements (CDEs) for collection in primary source PregPV studies that can be used to standardise data collection procedures and, thereby, improve data harmonisation and evidence synthesis capabilities. METHODS: This CDE reference framework was developed within the Innovative Medicines Initiative (IMI) ConcePTION project by experts in pharmacovigilance, pharmacoepidemiology, medical statistics, risk-benefit communication, clinical teratology, reproductive toxicology, genetics, obstetrics, paediatrics, and child psychology. The framework was produced through a scoping review of data collection systems used by established PregPV datasets, followed by extensive discussion and debate around the value, definition, and derivation of each data item identified from these systems. RESULTS: The finalised listing of CDEs comprises 98 individual data elements, arranged into 14 tables of related fields. These data elements are openly available on the European Network of Teratology Information Services (ENTIS) website ( http://www.entis-org.eu/cde ). DISCUSSION: With this set of recommendations, we aim to standardise PregPV primary source data collection processes to improve the speed at which high-quality evidence-based statements can be provided about the safety of medication use in pregnancy.


Asunto(s)
Investigación Biomédica , Farmacovigilancia , Embarazo , Femenino , Humanos , Niño , Recolección de Datos
13.
Adv Sci (Weinh) ; 10(14): e2204488, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36951493

RESUMEN

High-entropy (HE) metal chalcogenides are a class of materials that have great potential in applications such as thermoelectrics and electrocatalysis. Layered 2D transition-metal dichalcogenides (TMDCs) are a sub-class of high entropy metal chalcogenides that have received little attention to date as their preparation currently involves complicated, energy-intensive, or hazardous synthetic steps. To address this, a low-temperature (500 °C) and rapid (1 h) single source precursor approach is successfully adopted to synthesize the hexernary high-entropy metal disulfide (MoWReMnCr)S2 . (MoWReMnCr)S2 powders are characterized by powder X-ray diffraction (pXRD) and Raman spectroscopy, which confirmed that the material is comprised predominantly of a hexagonal phase. The surface oxidation states and elemental compositions are studied by X-ray photoelectron spectroscopy (XPS) whilst the bulk morphology and elemental stoichiometry with spatial distribution is determined by scanning electron microscopy (SEM) with elemental mapping information acquired from energy-dispersive X-ray (EDX) spectroscopy. The bulk, layered material is subsequently exfoliated to ultra-thin, several-layer 2D nanosheets by liquid-phase exfoliation (LPE). The resulting few-layer HE (MoWReMnCr)S2 nanosheets are found to contain a homogeneous elemental distribution of metals at the nanoscale by high angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) with EDX mapping. Finally, (MoWReMnCr)S2 is demonstrated as a hydrogen evolution electrocatalyst and compared to 2H-MoS2 synthesized using the molecular precursor approach. (MoWReMnCr)S2 with 20% w/w of high-conductivity carbon black displays a low overpotential of 229 mV in 0.5 M  H2 SO4 to reach a current density of 10 mA cm-2 , which is much lower than the overpotential of 362 mV for MoS2 . From density functional theory calculations, it is hypothesised that the enhanced catalytic activity is due to activation of the basal plane upon incorporation of other elements into the 2H-MoS2 structure, in particular, the first row TMs Cr and Mn.

14.
Dalton Trans ; 52(10): 3072-3084, 2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36779844

RESUMEN

We report a facile and low temperature synthesis of Ga- and In-doped CdS nanoparticles from molecular precursors. Diethyldithiocarbamate complexes of Cd(II), Ga(III), and In(III), were synthesised and decomposed in tandem through solventless thermolysis, producing Ga- or In-doped CdS. The resultant MxCd1-xS1+0.5x (where M = Ga/In at x values of 0, 0.02, 0.04, 0.06, 0.08 and 0.1) particulate powder was analysed by powder X-ray diffraction, which showed that both Ga (through all doping levels) and In (at doping levels <8 mol%) were successfully incorporated into the hexagonal CdS lattice without any impurities. Raman spectroscopy also showed no significant change from CdS. Scanning electron microscopy and energy dispersive X-ray spectroscopy were used to investigate the morphology and elemental dispersion through the doped CdS materials, showing homogenous incorporation of dopant. The optical and luminescent properties of the doped MxCd1-xS1+0.5x materials were examined by UV-Vis absorption and photoluminescence spectroscopies respectively. All materials were found to exhibit excitonic emission, corresponding to band gap energies between 2.7 and 2.9 eV and surface defect induced emission which is more prominent for Ga than for In doping. Additionally, moderate doping slows down charge carrier recombination by increasing the lifetimes of excitonic and surface state emissions, but particularly for the latter process.

15.
ACS Appl Mater Interfaces ; 15(10): 13097-13107, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36854123

RESUMEN

We present a novel method to significantly enhance the thermoelectric performance of ceramics in the model system SrTi0.85Nb0.15O3 through the use of the precursor ammonium tetrathiomolybdate (0.5-2% w/w additions). After sintering the precursor-infused green body at 1700 K for 24 h in 5% H2/Ar, single-crystal-like electron transport behavior developed with electrical conductivity reaching ∼3000 S/cm at ∼300 K, almost a magnitude higher than that in the control sample. During processing, the precursor transformed into MoS2, then into MoOx, and finally into Mo particles. This limited grain growth promoted secondary phase generation but importantly helped to reduce the grain boundary barriers. Samples prepared with additions of the precursor exhibited vastly increased electrical conductivity, without significant impact on Seebeck coefficients giving rise to high power factor values of 1760 µW/mK2 at ∼300 K and a maximum thermoelectric figure-of-merit zT of 0.24 at 823 K. This processing strategy provides a simple method to achieve high charge mobility in polycrystalline titanate and related materials and with the potential to create "phonon-glass-electron-crystal" oxide thermoelectric materials.

16.
Br J Clin Pharmacol ; 89(2): 470-482, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36264908

RESUMEN

AIMS: Moore's law predicts the doubling of complexity of integrated circuits every 2 years; Kryder's corollary assumes a doubling of data storage every 13 months. With the increasing volume of legislation, pharmacovigilance systems today are inherently complex, and the emphasis has shifted from reactive (responding to emerging risks) to planned, active, risk-proportionate approaches operating throughout the life cycle of medicines. METHODS: Exploration of the drivers for increasing complexity of pharmacovigilance systems, focusing on regulatory environment, data management and evaluation. RESULTS: Evaluation of postmarketing data plays an increasingly important role in pharmacovigilance. There is great interest on the part of all stakeholders in optimizing the use of these data. Innovative approaches, including pharmacogenetics and passive measures (sensors), will lead to increased complexity and volumes of data and inevitably to an increase in the volume of case reports. There is a multiplicity of regulations and guidelines on how to manage these data, with an inherent lack of harmonization. CONCLUSION: We summarize the current characterization of safety data types, sources and the classification of these data. Using this benchmark, we discuss the future requirements of an effective pharmacovigilance ecosystem, keeping the principle of parsimony in mind. In this complex, continuously and rapidly changing environment, there is a need for a return to simplicity and pragmatism. The application of Occam's razor could help to support the rapid provision of new, affordable medicines with a positive benefit to risk profile.


Asunto(s)
Ecosistema , Farmacovigilancia , Humanos
17.
Biol Psychiatry Glob Open Sci ; 2(2): 106-114, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36325160

RESUMEN

Background: Methylphenidate is among the most prescribed medications for treating attention-deficit/hyperactivity disorder (ADHD). However, nearly half of pediatric patients with ADHD do not respond to methylphenidate treatment. Pharmacogenetic testing can aid in identifying patients for whom methylphenidate is unlikely to be safe or effective, leading to improved methylphenidate outcomes and increased use of alternative treatment options for ADHD. This article aimed to summarize findings from studies of the ADRA2A gene variant, rs1800544, and its association with methylphenidate outcomes in ADHD. Methods: We systematically reviewed and meta-analyzed available literature on the impact of rs1800544 on methylphenidate outcomes in ADHD. Results: Fourteen studies met inclusion criteria for review, 9 of which were eligible for meta-analysis. The included studies compared methylphenidate outcomes in patients with ADHD categorized by rs1800544 genotype. G-allele carriers experienced significantly greater improvements in ADHD symptom scores (Swanson, Nolan, and Pelham Version-IV Scale or ADHD Rating Scale-IV) relative to noncarriers (odds ratio 3.08, 95% confidence interval 1.71-5.56, p = .0002) and greater response rates as measured by a ≥50% improvement in symptom scores (odds ratio 2.68, 95% confidence interval 1.23-5.82, p = .01); no significant difference in response rate as measured by Clinical Global Impressions score ≤2 was found. Stouffer's z-score method showed significant improvement across all methylphenidate outcomes in G-allele carriers relative to noncarriers (z = 3.03, p = .002). Conclusions: These findings suggest that carriers of rs1800544 may have improved ADHD outcomes following methylphenidate treatment. However, the extent to which these improvements are clinically impactful remain unclear. Additional studies are required to determine if rs1800544 carrier status should influence clinical recommendations for treatment of ADHD symptoms.

18.
Nano Lett ; 22(20): 8045-8051, 2022 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-36194549

RESUMEN

We have synthesized the first reported example of quantum confined high-entropy (HE) nanoparticles, using the lanthanide oxysulfide, Ln2SO2, system as the host phase for an equimolar mixture of Pr, Nd, Gd, Dy, and Er. A uniform HE phase was achieved via the simultaneous thermolysis of a mixture of lanthanide dithiocarbamate precursors in solution. This was confirmed by powder X-ray diffraction and high-resolution scanning transmission electron microscopy, with energy dispersive X-ray spectroscopic mapping confirming the uniform distribution of the lanthanides throughout the particles. The nanoparticle dispersion displayed a significant blue shift in the absorption and photoluminescence spectra relative to our previously reported bulk sample with the same composition, with an absorption edge at 330 nm and a λmax at 410 nm compared to the absorption edge at 500 nm and a λmax at 450 nm in the bulk, which is indicative of quantum confinement. We support this postulate with experimental and theoretical analysis of the bandgap energy as a function of strain and surface effects (ligand binding) as well as calculation of the exciton Bohr radiii of the end member compounds.

19.
Nat Commun ; 13(1): 5490, 2022 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-36123337

RESUMEN

Over the last half century in the United States, the per-hectare volume of wood in trees has increased, but it is not clear whether this increase has been driven by forest management, forest recovery from past land uses, such as agriculture, or other environmental factors such as elevated carbon dioxide, nitrogen deposition, or climate change. This paper uses empirical analysis to estimate the effect of elevated carbon dioxide on aboveground wood volume in temperate forests of the United States. To accomplish this, we employ matching techniques that allow us to disentangle the effects of elevated carbon dioxide from other environmental factors affecting wood volume and to estimate the effects separately for planted and natural stands. We show that elevated carbon dioxide has had a strong and consistently positive effect on wood volume while other environmental factors yielded a mix of both positive and negative effects. This study, by enabling a better understanding of how elevated carbon dioxide and other anthropogenic factors are influencing forest stocks, can help policymakers and other stakeholders better account for the role of forests in Nationally Determined Contributions and global mitigation pathways to achieve a 1.5 degree Celsius target.


Asunto(s)
Dióxido de Carbono , Dióxido de Nitrógeno , Dióxido de Carbono/metabolismo , Fertilización , Bosques , Árboles/metabolismo , Estados Unidos
20.
Pharmacoepidemiol Drug Saf ; 31(11): 1131-1139, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35996833

RESUMEN

Exponential growth of health-related data collected by digital tools is a reality within pharmaceutical and medical device research and development. Data generated through digital tools may be categorized as relevant to efficacy and/or safety. The enormity of these data requires the adoption of new approaches for processing and evaluation. Recognition of patterns within the safety data is vital for sponsors seeking regulatory approval for their new products. Nontraditional data sources may contain relevant safety information; early evaluation of these data will help to determine the product safety profile. Advanced technologies have allowed the development of digital tools to screen these data, which in some situations are classified as software as a medical devices and subject to clinical evaluation and post-marketing surveillance. Artificial intelligence may help to reduce or even eliminate noise from within these data, allowing safety experts to focus on the most pertinent evidence. We propose a data typology and provide considerations on how to define adverse events within different types of data, even where no human reporter exists. Proposals are made for the automation of screening processes. We consider validation aspects to support solutions that are proven to produce reliable results, and to deliver trusted outputs to stakeholders.


Asunto(s)
Inteligencia Artificial , Atención a la Salud , Humanos , Preparaciones Farmacéuticas , Programas Informáticos
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