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1.
J Pharm Biomed Anal ; 246: 116189, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38733763

RESUMEN

Portable near-infrared (NIR) spectrophotometers have emerged as valuable tools for identifying substandard and falsified pharmaceuticals (SFPs). Integration of these devices with chemometric and machine learning models enhances their ability to provide quantitative chemical insights. However, different NIR spectrophotometer models vary in resolution, sensitivity, and responses to environmental factors such as temperature and humidity, necessitating instrument-specific libraries that hinder the wider adoption of NIR technology. This study addresses these challenges and seeks to establish a robust approach to promote the use of NIR technology in post-market pharmaceutical analysis. We developed support vector machine and partial least squares regression models based on binary mixtures of lab-made ciprofloxacin and microcrystalline cellulose, then applied the models to ciprofloxacin dosage forms that were assayed with high performance liquid chromatography (HPLC). A receiver operating characteristic (ROC) analysis was performed to set spectrophotometer independent NIR metrics to evaluate ciprofloxacin dosage forms as "meets standard," "needs HPLC assay," or "fails standard." Over 200 ciprofloxacin tablets representing 50 different brands were evaluated using spectra acquired from three types of NIR spectrophotometer with 85% of the prediction agreeing with HPLC testing. This study shows that non-brand-specific predictive models can be applied across multiple spectrophotometers for rapid screening of the conformity of pharmaceutical active ingredients to regulatory standard.


Asunto(s)
Ciprofloxacina , Espectroscopía Infrarroja Corta , Comprimidos , Ciprofloxacina/análisis , Ciprofloxacina/química , Comprimidos/análisis , Espectroscopía Infrarroja Corta/métodos , Espectroscopía Infrarroja Corta/normas , Cromatografía Líquida de Alta Presión/métodos , Calibración , Análisis de los Mínimos Cuadrados , Máquina de Vectores de Soporte , Celulosa/química , Celulosa/análisis , Medicamentos Falsificados/análisis
2.
Clim Change ; 172(1-2): 1, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35529022

RESUMEN

It has been claimed that COVID-19 public stimulus packages could be sufficient to meet the short-term energy investment needs to leverage a shift toward a pathway consistent with the 1.5 °C target of the Paris Agreement. Here, we provide complementary perspectives to reiterate that substantial, broad, and sustained policy efforts beyond stimulus packages will be needed for achieving the Paris Agreement long-term targets. Low-carbon investments will need to scale up and persist over the next several decades following short-term stimulus packages. The required total energy investments in the real world can be larger than the currently available estimates from integrated assessment models (IAMs). Existing databases from IAMs are not sufficient for analyzing the effect of public spending on emission reduction. To inform what role COVID-19 stimulus packages and public investments may play for reaching the Paris Agreement targets, explicit modelling of such policies is required.

4.
Environ Sci Technol ; 44(1): 210-5, 2010 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-19950945

RESUMEN

Climate policy will create both disincentives and incentives for tropical deforestation. Disincentives if the carbon emissions from forest clearing are priced, as is currently being discussed within the United Nations Framework Convention on Climate Change (UNFCCC); incentives as a price on carbon will increase the demand for carbon-neutral energy sources, including bioenergy, making deforestation for biomass cultivation increasingly profitable. The question is whether the increased cost for forest clearing, through the price on carbon emissions, will be enough to counter-balance the increased profitability of deforestation through the escalating value of agricultural land. In an attempt to answer this question we analyze the profitability of tropical deforestation and subsequent bioenergy production, taking oil palm plantations as an illustrative example. We estimate that deforesting for palm oil bioenergy production is likely to remain highly profitable, even in the face of a price on the carbon emissions from forest clearing. Current efforts to include carbon emissions from tropical deforestation in a future international climate regime, while a step in the right direction, may therefore not suffice as protection for the world's tropical forests. Additional, and stronger, protection measures for the world's tropical forests will still be needed.


Asunto(s)
Carbono/análisis , Conservación de los Recursos Naturales , Árboles , Clima Tropical , Ambiente , Efecto Invernadero
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