Energy is an essential and obligatory prerequisite of life. Indoor air pollution is one of the biggest environmental problems in the world being specifically concentrated in resource limited settings. Inspite of the availability of cleaner fuel technologies, people in resource limited setting still depend on traditional fuel to meet their basic needs resulting even in premature deaths. In Nepal people in rural areas are the pre-dominant users of biomass fuel, there is limited research focusing on rural areas particularly; women as they spend most of their time in kitchen.
Reports were extensively searched for literature using preset keywords in English language peer-reviewed journals databases PubMed and Google Scholar published between the years 2005 to 2020. Citation details were examined, titles and abstracts screened for eligibility and if relevant, full text was also reviewed in greater detail. Findings were then presented primarily under two bold themes: Household fuel consumption: existing theories and evidence; and health impact of indoor air pollution. Several health effects were reported of indoor air pollution including respiratory illnesses, cardiovascular diseases, cancer, endocrine system disruption and pregnancy complications.
These exposures almost double the health risks predominantly among children and women of rural communities as they are directly involved in household activities causing air pollution.
Based on our review of evidence, women and children of rural households were the major victims. Further, determinants of household fuel consumption and health effects should be considered while formulating policies https://biodas.org/
in regard to promoting accessibility of clean fuels and reducing household air pollutants.
Primary facility for traceable measurement of the BSSRDF
The bidirectional scattering-surface reflectance distribution function (BSSRDF) is the function that describes the variation of the radiance of the elementary areas of a surface with respect to the directionally incident radiant flux on that surface. Measurements of the BSSRDF are important for characterizing the translucency of objects and for obtaining those optical parameters affecting volume scattering.
However, to date, no traceable measurements of this function are available, since, likely due to its technical complexity, no standard measurement procedure has been established. We have developed a primary facility for measuring the BSSRDF based on a gonio-spectrophotometer with spatial resolution in the collection, spectral resolution in the irradiation, and angular resolution both for irradiation and collection directions.
The BSSRDF of twelve homogeneous and translucent samples (with controlled values for the mean diameter of the scattering particles and their concentration) have been measured with relative uncertainties below 3% inside the irradiated area. Some results are shown and commented. This primary facility will allow the BSSRDF scale to be transferred to other instruments.
Towards a patient-specific traceable quantification of SPECT/CT-based radiopharmaceutical distributions
Quantitative SPECT/CT imaging is currently the state-of-the-art for peri-therapeutic monitoring of radiopharmaceutical distributions. Due to poor resolution, however, the verification of SPECT/CT-based activity distributions is of particular importance. Due to the lack of a ground truth in patient measurements, phantoms are commonly used as a substitute for clinical validation of quantitative SPECT/CT. Due to the time-consuming and erroneous preparation of multi-compartment phantoms, e.g. for the kidney, the usually very complex internal activity distributions are typically replaced by one- or two-compartment models. To provide a simplified solution for generating inhomogeneous activity distributions, this work presents a methodology for designing single-compartment phantoms that mimic inhomogeneous spatial activity distributions by internal filling structures of different volume fractions.
Methods: A series of phantoms with different filling structures was designed, 3D printed, and measured. After assessing the feasibility of the presented approach in a simple geometry, a set of three patient-specific kidney phantoms was designed based on the contrast-enhanced CT of a patient suffering from metastatic castration-resistant prostate cancer. Internal gyroid structures of different wall thickness were used in renal medulla and cortex to reproduce the inhomogeneous activity distribution observed in a peri-therapeutic SPECT/CT acquisition 24-hours post [177Lu]Lu-PSMA injection (apparent activity concentration ratios of 1:1, 1:3.5, and 1:7.5). After 3D printing, SPECT/CT experiments were performed and the results were compared to the patient data for different reconstruction settings (iterations, subsets, and post-filtering).
Results: A good agreement was found between phantom designs and fabricated phantoms (based on high-resolution CT). No internal filling structures were visible in any of the SPECT images, indicating a sufficiently small feature size. While a good visual and quantitative agreement was achieved for certain combinations of filling structure and reconstruction, a histogram analysis indicated an even more complex activity distribution in the patient than represented by the two compartments assumed in our model.
Conclusion: The proposed methodology provides patient-specific phantoms mimicking inhomogeneous activity distributions while using a single stock solution, thus simplifying the filling process and reducing uncertainties in the activity determination. This enables an unprecedented possibility for patient-specific evaluation of radiopharmaceutical uptake, reducing uncertainties in internal dosimetry and individualized treatments.
Mass balance method for SI-traceable purity assignment of synthetic oxytocin
- Oxytocin is not only a significant peptide drug for enhancing uterine contractions, but also an emerging biomarker and therapeutic target of mental disorders in clinical practice. There is a pressing need for the standardization of oxytocin assays because of its low pharmaceutical quality and large variations among measurement approaches. International System of Units (SI)-traceable analytical methods and well-characterized pure reference materials are urgently needed to set up standard reference measurement systems in laboratory medicine, ensuring the accuracy and comparability of test results.
- Herein, the purity assignment of a synthetic oxytocin containing a disulfide linkage was established based on a mass balance method, which had never been performed for a cross-linked peptide. An in-house validated liquid chromatography-high-resolution tandem mass spectrometry method was developed for the determination of structurally-related impurities in the study material. Twenty-one structurally-related impurities including deamidations, oxidations, and amino acid insertions, etc. ranging from 0.05 mg g-1 to 15.65 mg g-1 were identified and quantified by applying a hierarchy calibration concept.
- This study subsequently discusses a fit for purpose assessment for non-peptide related impurities including water, non-volatile counterions, inorganic elements, and volatile organic compounds that were determined using coulometric Karl Fischer titration, ion chromatography, inductively coupled plasma mass spectrometry, and headspace gas chromatography-mass spectrometry, respectively. The resulting assigned value (796.5 mg g-1) is determined to be traceable to SI associated with a small measurement uncertainty of 6.5 mg g-1 (k = 2). The method developed in this study has been verified through an international key comparison jointly coordinated by the Bureau International des Poids et Mesures and the National Institute of Metrology.
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