C-Type Natriuretic Peptide (32-53) ELISA Kit

Polymer nanocomposite-based sensors were prepared using cellulose acetate (CA), carbon nanoparticles (CNPs), and manganese dioxide (MnO2) nanorods to detect and to understand the sensing mechanism of 2-methylcyclopentanone vapor. A sensor with a mass ratio of 1: 1.5: 3 of MnO2/CNPs/CA as well as MnO2/CA and MnO2/CNP composite and MnO2 sensors were prepared. The sensor with the three sensing materials combined exhibited an enhancement of response for 2-methylcyclopentanone vapor, ascribed to a synergistic effect between MnO2/CNPs/CA. An in situ Fourier-transform infrared (FTIR)-combined online LCR meter setup was used to understand the sensing mechanism of the sensor. The sensing mechanism involved a deep oxidation decomposition of the analyte to CO2. This was confirmed from the in situ FTIRcombined online LCR meter results, where a new distinct CO2 bending mode IR band was recorded. To optimize the performance of the sensor, the composites were prepared by varying the amount of metal oxide added into the composites; sensor A (composition of mass ratio 1: 1.5: 3), sensor B (composition of mass ratio 2: 1.5: 3), and sensor C (composition of mass ratio 2.5: 1.5: 3); their compositions are MnO2/CNPs/CA. The performance of sensor B was higher than that of the other two sensors. The sensors also show relatively good response-recovery time. All fabricated sensors were found to have the sensing ability regenerated after the analyte was removed from the system without losing its sensing and recovery abilities. The structural and morphological features of the samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy.

Purpose Soil organic carbon (SOC) is an important parameter determining soil fertility and sustaining soil health. How C, N, and P contents and their stoichiometric ratios (C/N/P) regulate the nutrient availability, and SOC stabilization mechanisms have not been comprehensively explored, especially in response to long-term fertilization. The present study aimed to determine how the long-term mineral and manure fertilization influenced soil C/N/P ratios and various protection mechanisms underlying the stabilization of OC along with profile in a cropland soil. Materials and methods The soil was sampled from five depths, viz., 0-20 cm, 20-40 cm, 40-60 cm, 60-80 cm, and 80-100 cm, from plots comprising wheat-maize-soybean rotation system subjected to the long-term (35 years) manure and mineral fertilizer applications. Results and discussion Results revealed that the soil C, N, P stoichiometry and their contents in topsoil depths (0-20 and 20-40 cm) and subsoil depths (40-60, 60-80, and 80-100 cm) varied significantly (p < 0.01) among the soil layers. Compared with CK, the C, N, and P contents were significantly higher (p < 0.05) in NPKM in the topsoil layers, while M alone increased these contents throughout the subsoil. Overall, the C, N, and P contents and their stoichiometry decreased with the increase in depth. Regression analysis showed that C/N, C/P, and N/P ratios associated significantly with the OC fractions in the topsoil layers only. These negative correlations indicated that these ratios significantly influence the C stabilization in the surface layers. However, the results warrant further investigations to study the relationship between soil and microbial stoichiometry and SOC at various depths. Conclusions Long-term manure applications improved the C sequestration not only in the topsoil but also in the deep layers; hence, these facts can be considered relevant for fertilizer recommendations in cropping systems across China.