Flexible Chitosan-Based Capacitive Humidity Sensors for Respiratory Monitoring.

As one of the most important human health indicators, respiratory status is an important basis for the diagnosis of many diseases. However, the high cost of respiratory monitoring makes its use uncommon. This study introduces a low-cost, wearable, flexible humidity sensor for respiratory monitoring. Solution-processed chitosan (CS) placed on a polyethylene terephthalate substrate was used as the sensing layer. An Arduino circuit board was used to read humidity-sensitive voltage changes. The CS-based sensor demonstrated capacitive humidity sensitivity, whereby the capacitance instantly increased from 10-2 to 30 nF when the environmental humidity changed from 43% to 97%. The capacitance logarithm sensitivity and response voltage change was 35.9 pF/%RH and 0.8 V in the RH range from 56% to 97%. And the voltage variation between inhalation and exhalation was ~0.5 V during normal breathing. A rapid response time of ~0.7 s and a recovery time of ~2 s were achieved during respiration testing. Breathing modes (i.e., normal breathing, rest breathing, deep breathing, and fast breathing) and tonal changes during speech could be clearly distinguished. Therefore, such sensors provide a means for economical and convenient wearable respiratory monitoring, and they have the potential to be used for daily health examinations and professional medical diagnoses.

Root Metabolism and Effects of Root Exudates on the Growth of Ralstonia solanacearum and Fusarium moniliforme Were Significantly Different between the Two Genotypes of Peanuts.

Wild peanut species Arachis correntina (A. correntina) had a higher continuous cropping tolerance than peanut cultivars, closely correlating with the regulatory effects of its root exudates on soil microorganisms. To reveal the resistance mechanism of A. correntina to pathogens, we adopted transcriptomic and metabolomics approaches to analyze differentially expressed genes (DEGs) and differentially expressed metabolites (DEMs) between A. correntina and peanut cultivar Guihua85 (GH85) under hydroponic conditions. Interaction experiments of peanut root exudates with Ralstonia solanacearum (R. solanacearum) and Fusarium moniliforme (F. moniliforme) were carried out in this study. The result of transcriptome and metabolomics association analysis showed that there were fewer up-regulated DEGs and DEMs in A. correntina compared with GH85, which were closely associated with the metabolism of amino acids and phenolic acids. Root exudates of GH85 had stronger effects on promoting the growth of R. solanacearum and F. moniliforme than those of A. correntina under 1 and 5 percent volume (1% and 5%) of root exudates treatments. Thirty percent volume (30%) of A. correntina and GH85 root exudates significantly inhibited the growth of two pathogens. The exogenous amino acids and phenolic acids influenced R. solanacearum and F. moniliforme showing concentration effects from growth promotion to inhibition as with the root exudates. In conclusion, the greater resilience of A. correntina) to changes in metabolic pathways for amino acids and phenolic acids might aid in the repression of pathogenic bacteria and fungi.

Angiotensin-converting enzyme insertion/deletion gene polymorphisms associated with risk of atrial fibrillation: A meta-analysis of 23 case-control studies.

AIMS: The renin-angiotensin-aldosterone system is important to the development of atrial fibrillation (AF). A lot of research has focused on the relationship between angiotensin-converting enzyme (ACE) insertion (I) /deletion (D) gene polymorphisms and AF, with inconsistent results. A meta-analysis was carried out to find the correlation between ACE I/D gene polymorphisms and AF. METHODS: Data were extracted from articles published before September 2013 on ACE I/D polymorphisms and AF in Embase, PubMed, WanFangData, and China National Knowledge Infrastructure. RESULTS: The recessive model found that ACE I/D gene polymorphisms were related to AF (odds ratio (OR) = 1.61, 95% confidence interval (CI) = 1.16-1.72). Subgroup analysis showed a significant association in the recessive model for Asian (OR = 1.40, 95% CI = 1.19-1.80) and Caucasian (OR = 1.42, 95% CI = 1.01-1.99) populations. CONCLUSIONS: ACE I/D gene polymorphisms and AF are significantly related to ethnicity. Individuals with the ACE D/D genotype appear to be at higher risk of AF.