Publications by authors named "R M Hadfield"

The direct detection of singlet-state oxygen (O) constitutes the holy grail dosimetric method for type-II photodynamic therapy (PDT), a goal that can be quantified using multispectral singlet oxygen near-infrared luminescence dosimetry (MSOLD). The optical properties of tissues, specifically their scattering and absorption coefficients, play a crucial role in determining how the treatment and luminescence light are attenuated. Variations in these properties can significantly impact the spatial distribution of the treatment light and hence the generation of singlet oxygen and the detection of singlet oxygen luminescence signals.

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Article Synopsis
  • The northern North American Cordillera is a crucial area for biodiversity, particularly for unique lichens like the endangered wanderlust lichens which thrive in arid steppe habitats across several western states.
  • The study focuses on understanding the evolutionary background and geographic distribution of these lichens (Rhizoplaca species) by analyzing their genetic information and using species distribution models.
  • Findings indicate distinct genetic lineages linked to geographic regions, highlighting the importance of both dispersal and historical separation in the evolution of these lichens.
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For centuries, humans occupying arid regions of North America have maintained an intricate relationship with Agave (Agavoideae, Asparagaceae). Today Agave cultivation, primarily for beverage production, provides an economic engine for rural communities throughout Mexico. Among known dryland-farming methods, the use of rock piles and cattle-grazed areas stand out as promising approaches for Agave cultivation.

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Direct detection of singlet-state oxygen ([O]) constitutes the holy grail dosimetric method for type II PDT, a goal that can be quantified using multispectral singlet oxygen dosimetry (MSOLD). However, the short lifetime and extremely weak nature of the singlet oxygen signal produced has given rise to a need to improve MSOLD signal-to-noise ratio. This study examines methods for optimizing MSOLD signal acquisition, specifically employing an orthogonal arrangement between detection and PDT treatment light, consisting of two fiber optics - connected to a 632-nm laser and an InGaAs detector respectively.

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Background: Asthma and chronic obstructive pulmonary disease (COPD) cause a considerable burden of morbidity and mortality in low-income and middle-income countries (LMICs). Access to safe, effective, quality-assured, and affordable essential medicines is variable. We aimed to review the existing literature relating to the availability, cost, and affordability of WHO's essential medicines for asthma and COPD in LMICs.

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