We report on the development and performance of a gas sensor based on a distributed feedback quantum cascade laser operating in continuous wave at room temperature for simultaneous measurement of nitrous oxide (N(2)O) and methane (CH(4)) concentrations at ground level. The concentrations of the gases are determined by a long path infrared diode laser absorption spectroscopy. The long-term stability of the instrument is evaluated using the Allan variance technique. A preliminary evaluation of the instrument performance is realized by in situ measurements of N(2)O and CH(4) concentrations at ground level during 1 day. The sensor has also been applied to study the time response of N(2)O concentrations to a fertilizer addition in a soil sample and for the comparison between various types of soils.
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http://dx.doi.org/10.1364/ao.47.001206 | DOI Listing |
BMJ Open Qual
January 2025
Professor Department of Obstetrics and Gynaecology, Lady Hardinge Medical College, New Delhi, India.
Background: Allowing a birth companion is the basic right of a mother and is identified as an important component of respectful maternity care. The implementation of this intervention has been a challenge in heavy-load public health facilities in India.
Local Problem: Despite the proven benefits of the presence of birth companions on maternal-fetal outcomes, there was no policy of allowing birth companions in our hospital.
Int J Biol Macromol
January 2025
School of Textile Science and Engineering, Tiangong University, Tianjin 300387, China.
The importance of continuous and reliable pulse wave monitoring is constantly being increased in health signal monitoring and disease diagnoses. Flexible pressure sensors with high sensitivity, low hysteresis and fast response time are an effective means for monitoring pulses. Herein, a special wave-shaped layered porous structure of carbonized wood cellulose sponge (CWCS) was constructed based on natural wood (NW).
View Article and Find Full Text PDFPediatr Neurol
January 2025
Faculty of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain; Pediatrics Research Group, Institut de Recerca Sant Pau (IR-Sant Pau), Barcelona, Spain; Pediatric Neurology Unit, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
Background: Dravet syndrome (DS) is a severe developmental and epileptic encephalopathy associated with loss-of-function variants in the SCN1A gene. Although predominantly expressed in the central nervous system, SCN1A is also expressed in the heart, suggesting a potential link between neuronal and cardiac channelopathies. Additionally, DS carries a high risk of sudden unexpected death in epilepsy (SUDEP).
View Article and Find Full Text PDFJ Gerontol B Psychol Sci Soc Sci
January 2025
Department of Geriatric Medicine, Radboud university medical center, Nijmegen, The Netherlands.
Objective: Maintaining a strong social network in later life can be challenging due to limited resources, life events, and changes in health. Social internet use provides an accessible way for communication that is less susceptible to age-related challenges. Although social internet use is increasingly used by older adults, we do not know how social internet use shapes older adults' offline networks.
View Article and Find Full Text PDFJ Cereb Blood Flow Metab
January 2025
Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK.
To what extent sildenafil, a selective inhibitor of the type-5 phosphodiesterase modulates systemic redox status and cerebrovascular function during acute exposure to hypoxia remains unknown. To address this, 12 healthy males (aged 24 ± 3 y) participated in a randomized, placebo-controlled crossover study involving exposure to both normoxia and acute (60 min) hypoxia (Fi = 0.14), followed by oral administration of 50 mg sildenafil and placebo (double-blinded).
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