scholarly journals A Panax notoginseng Root Tip Meristem Biosensor and Its Sensing Kinetics for Five Important Nitrogen Nutrients

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Zi Qing Zheng ◽  
Bo Niu ◽  
Ding Qiang Lu ◽  
Guang Chang Pang
Keyword(s):  
Sodium Nitrate ◽  
Inorganic Nitrogen ◽  
Low Cost ◽  
Panax Notoginseng ◽  
Interaction Constant ◽  
Electrode System ◽  
Plant Age ◽  
Root Tip ◽  
Sodium Glutamate ◽  
Nitrogen Nutrients

Plants absorb nitrogen mainly through their roots. Nitrogen sensing is required for the absorption and transport of different nitrogen nutrients. In this study, we constructed biosensors with immobilized Panax notoginseng root tip meristems based on a three-electrode system and successfully determined the kinetics of the interactions between the P. notoginseng root tip meristems and five important nitrogen nutrients, namely, urea, sodium nitrate, sodium glutamate, disodium inosinate, and disodium guanylate. We discovered that the biosensor’s sensing kinetics was similar to the enzyme–substrate kinetics, and the receptor–ligand interconnected allosteric interaction constant Ka (mol/L), analogous to the Michaelis constant, was calculated. The result showed that the root tip meristems of two- to four-year-old P. notoginseng plants had a higher capacity to sense inorganic nitrogen nutrients (sodium nitrate and urea) than the three organic nitrogen nutrients. The ability of the plants to sense inorganic nitrogen nutrients decreased with an increase in plant age. The sensing sensitivity of four-year-old P. notoginseng plants to disodium inosinate and disodium guanylate was 100- to 10,000-fold lower than that of the two- and three-year-old plants. Additionally, the capability to sense sodium glutamate decreased initially and then increased with an increase in plant age. The biosensors reached an ultra-sensitive level ( 1 × 10 − 22  mol/L) in sensing the five nitrogen nutrients and exhibited advantages such as good stability and reproducibility, low cost, a simple structure, and a rapid response, providing a new approach for quantitative determination of the capability of plants to sense different nitrogen nutrients.

scholarly journals Construction of a Ginseng Root-Meristem Sensor and a Sensing Kinetics Study on the Main Nitrogen Nutrients

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 681
Author(s):  
Shiang Wang ◽  
Dingqiang Lu ◽  
Guangchang Pang
Keyword(s):  
Limit Of Detection ◽  
Inorganic Nitrogen ◽  
Equilibrium Analysis ◽  
Ginseng Root ◽  
Continuous Cropping ◽  
Sodium Glutamate ◽  
Sensor Sensitivity ◽  
Group A ◽  
Hardy Weinberg Equilibrium ◽  
Nitrogen Nutrients

Severe continuous cropping obstacles exist in ginseng cultivation. In order to assess these obstacles, a “sandwich” ginseng root tissue sensor was developed for the kinetic determination of five nitrogen nutrients. The results showed that the sensing parameters of the sensor reached an ultrasensitive level (limit of detection up to 5.451 × 10−24 mol/L) for the five nitrogen nutrients, and exhibited good stability and reproducibility. In the order of two-, four-, and six-year-old ginseng plants, the sensitivity to inorganic nitrogen nutrients (sodium nitrate and urea) showed an upward trend following an initial decline (the interconnected allosteric constant Ka values acted as the parameter). The fluctuations in sensor sensitivity to organic nitrogen nutrients, specifically nucleotides (disodium inosinate and disodium guanylate), were relatively small. The sensor sensitivity of two-, four-, and six-year-old ginseng plants to sodium glutamate was 9.277 × 10−19 mol/L, 6.980 × 10−21 mol/L, and 5.451 × 10−24 mol/L, respectively. Based on the survival rate of the seedlings and mortality rate of the ginseng in each age group, a Hardy–Weinberg equilibrium analysis was carried out. The results showed that the sensing ability of the root system to sodium glutamate may be an important factor affecting its survival under continuous cropping obstacles with increasing age.

scholarly journals Economic pulse electrodeposition for flexible CuInSe2 solar cells

2020 ◽  
Vol 9 (3) ◽  
Author(s):  
Sreekanth Mandati ◽  
Prashant Misra ◽  
Divya Boosagulla ◽  
Tata Naransinga Rao ◽  
Bulusu V. Sarada
Keyword(s):  
Solar Cells ◽  
Low Cost ◽  
Electrode System ◽  
Pulse Electrodeposition ◽  
Small Scale ◽  
Complexing Agents ◽  
Large Area ◽  
Advanced Technique ◽  
Glass Substrates ◽  
Energy Applications

Abstract Electrodeposition is one of the leading non-vacuum techniques for the fabrication of CuInSe2 (CIS)-based solar cells. In the present work, pulse electrodeposition, an advanced technique, is utilized effectively for CIS absorber preparation devoid of any additives/complexing agents. An economic pulse electrodeposition is employed for the deposition of Cu/In stack followed by selenization to fabricate CIS absorbers on flexible and glass substrates. The approach uses a two-electrode system suitable for large area deposition and utilizes the fundamentals of pulse electrodeposition with appropriate optimization of parameters to obtain smooth Cu/In precursors. The selenized CIS absorbers are of 1 µm thick while possessing copper-poor composition (Cu/In ≈ 0.9) and tetragonal chalcopyrite phase. The fabricated devices have exhibited a power conversion efficiency of 5.2%. The technique can be further improved to obtain low-cost CIS solar cells which are suitable for various small-scale energy applications.

scholarly journals Molecular Identification of a Newly IsolatedBacillus subtilisBI19 and Optimization of Production Conditions for Enhanced Production of Extracellular Amylase

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Biplab Kumar Dash ◽  
M. Mizanur Rahman ◽  
Palash Kumar Sarker
Keyword(s):  
Inorganic Nitrogen ◽  
Low Cost ◽  
Nitrogen Sources ◽  
Tween 80 ◽  
Shake Flask Culture ◽  
Lauryl Sulfate ◽  
Enhanced Production ◽  
Amylase Production ◽  
Extracellular Amylase ◽  
Production Conditions

A study was carried out with a newly isolated bacterial strain yielding extracellular amylase. The phylogenetic tree constructed on the basis of 16S rDNA gene sequences revealed this strain as clustered with the closest members ofBacillussp. and identified asBacillus subtilisBI19. The effect of various fermentation conditions on amylase production through shake-flask culture was investigated. Rice flour (1.25%) as a cheap natural carbon source was found to induce amylase production mostly. A combination of peptone and tryptone as organic and ammonium sulfate as inorganic nitrogen sources gave highest yield. Maximum production was obtained after 24 h of incubation at 37°C with an initial medium pH 8.0. Addition of surfactants like Tween 80 (0.25 g/L) and sodium lauryl sulfate (0.2 g/L) resulted in 28% and 15% increase in enzyme production, respectively. Amylase production was 3.06 times higher when optimized production conditions were used. Optimum reaction temperature and pH for crude amylase activity were 50°C and 6.0, respectively. The crude enzyme showed activity and stability over a fair range of temperature and pH. These results suggest thatB. subtilisBI19 could be exploited for production of amylase at relatively low cost and time.

scholarly journals Spatial-temporal dynamics of N-cycle functional genes in a temperate Atlantic estuary (Douro, Portugal)

2020 ◽  
Vol 84 ◽  
pp. 205-216
Author(s):  
P Salgado ◽  
A Machado ◽  
AA Bordalo
Keyword(s):  
Microbial Communities ◽  
Temporal Dynamics ◽  
Inorganic Nitrogen ◽  
Functional Genes ◽  
Estuarine Ecosystem ◽  
Monthly Basis ◽  
N Cycle ◽  
Low Salinity ◽  
Key Factor ◽  
Nitrogen Nutrients

Understanding the spatial and seasonal dynamics of nitrogen (N)-cycle microbial communities is pivotal for the knowledge of N biogeochemistry. The present study addressed the spatial-temporal variability of nitrification (bacterial and archaeal amoA) and denitrification (nirS, nirK, and nosZI) key genes, as well as of non-denitrifying nitrous oxide (N2O) reducers (nosZII), coupled with key environmental variables, in an estuarine ecosystem (Douro, NW Portugal). Samples were collected on a monthly basis over 1 yr, key physical-chemical parameters were measured, and specific functional gene abundances were assayed. The results revealed a clear seasonality for nirS, nosZII, and bacterial and archaeal amoA abundance, with an increase during the winter/spring seasons. This period was especially characterized by high levels of dissolved oxygen, low temperature, low salinity, and increased turbidity. Indeed, turbidity emerged as the key factor controlling the distribution of nirS, nosZII bacterial, and archaeal amoA abundance. In contrast, the abundance of nosZI increased during the summer, while nirK abundance was enhanced from the fall to late spring. Additionally, the availability of dissolved inorganic nitrogen nutrients had no commensurable effect on N-cycle functional genes. This study of the annual variation of N-cycle functional genes in a temperate Atlantic estuary provides a major contribution to the understanding of how environmental factors potentially influence the distribution and abundance of N-cycle microbial communities.

scholarly journals Effects of carbon and nitrogen sources on production of proteases by Bacillus subtilis IC-5

2018 ◽  
Vol 44 (2) ◽  
pp. 285-292
Author(s):  
Sereen Gul ◽  
Mujeeb Ur Rahman ◽  
Mohammad Ajmal ◽  
Abdul Kabir Khan Achakzai ◽  
Asim Iqbal
Keyword(s):  
Bacillus Subtilis ◽  
Sodium Nitrate ◽  
Inorganic Nitrogen ◽  
Carbon Sources ◽  
Basal Medium ◽  
Nitrogen Sources ◽  
Neutral Protease ◽  
Carbon And Nitrogen Sources ◽  
Inorganic Nitrogen Source ◽  
Carbon And Nitrogen

The effects of various carbon and nitrogen sources were evaluated on production of proteases by Bacillus subtilis IC-5. Both type and concentration of carbon and nitrogen sources influenced the production of proteases. Among the carbon sources glucose was found to be the most effective. It gave maximum production at 2% w/v concentration i.e., 1875 and 950 U/ml, alkaline and neutral protease, respectively. The response of Bacillus subtilis IC-5 towards synthesis and excretion of enzymes varied with the type of nitrogen sources. The addition of organic nitrogen sources to basal medium repressed the synthesis of proteases while the addition of inorganic nitrogen source such as sodium nitrate was found to be the best stimulating for alkaline and neutral protease synthesis. Sodium nitrate enhanced the production up to 62.40 and 10.52% of alkaline and neutral protease, respectively against w.r.t. control.

A multi-parameter integrated chip system for water quality detection

2019 ◽  
Vol 33 (07) ◽  
pp. 1950041 ◽  
Author(s):  
Jiaqi Wang ◽  
Chao Bian ◽  
Yang Li ◽  
Jizhou Sun ◽  
Jianhua Tong ◽  
...  
Keyword(s):  
Water Quality ◽  
Temperature Sensor ◽  
Low Cost ◽  
Simultaneous Detection ◽  
Ruthenium Oxide ◽  
Water Quality Monitoring ◽  
Quality Parameters ◽  
Electrode System ◽  
Quality Monitoring ◽  
Quality Detection

Water pollution has always been an important issue threatening human health. Water quality monitoring is an important step to ensure water quality safety. Water quality parameters such as pH, temperature and conductivity are important indicators in water quality monitoring. In this paper, a multi-parameter water quality detection integrated chip system is studied, and multiple sensors are integrated on the same chip to realize the monitoring of conventional parameters such as pH, temperature and conductivity in drinking water. The chip system was processed by MEMS technology. A ruthenium oxide (RuO2) film is used for pH detection, and the sensor exhibits a super-Nernst response (62.88 mV/pH) in the range of pH 1.92–11.74. The patterned micro Pt film is used as the temperature sensor, and the three-wire orthogonal structure is used for temperature detection. The sensitivity of this temperature sensor is 5.517 [Formula: see text]/[Formula: see text]C in the range of 6 to 80[Formula: see text]C. Conductivity was measured by a four-electrode system, and the electrode constant was 1.667 cm[Formula: see text] measured between 0.994 and 21.167 mS/cm. The test results show that the multi-parameter integrated chip system can realize the simultaneous detection of pH, temperature and conductivity in water, and has the characteristics of miniaturization and low cost, and provides an effective way for simultaneous detection of water quality.

scholarly journals Recording extracellular neural activity in the behaving monkey using a semichronic and high-density electrode system

2016 ◽  
Vol 116 (2) ◽  
pp. 563-574 ◽  
Author(s):  
Germán Mendoza ◽  
Adrien Peyrache ◽  
Jorge Gámez ◽  
Luis Prado ◽  
György Buzsáki ◽  
...  
Keyword(s):  
Neural Activity ◽  
Large Scale ◽  
Low Cost ◽  
Pyramidal Cells ◽  
Macaque Monkey ◽  
Electrode System ◽  
High Density ◽  
Large Species ◽  
Population Activity ◽  
Different Depths

We describe a technique to semichronically record the cortical extracellular neural activity in the behaving monkey employing commercial high-density electrodes. After the design and construction of low cost microdrives that allow varying the depth of the recording locations after the implantation surgery, we recorded the extracellular unit activity from pools of neurons at different depths in the presupplementary motor cortex (pre-SMA) of a rhesus monkey trained in a tapping task. The collected data were processed to classify cells as putative pyramidal cells or interneurons on the basis of their waveform features. We also demonstrate that short time cross-correlogram occasionally yields unit pairs with high short latency (<5 ms), narrow bin (<3 ms) peaks, indicative of monosynaptic spike transmission from pre- to postsynaptic neurons. These methods have been verified extensively in rodents. Finally, we observed that the pattern of population activity was repetitive over distinct trials of the tapping task. These results show that the semichronic technique is a viable option for the large-scale parallel recording of local circuit activity at different depths in the cortex of the macaque monkey and other large species.

Croissance de la biomasse azotée du Phaeodactylum tricornutum (Bacillariophyceae) en cultures discontinues dialysante et non dialysante

1992 ◽  
Vol 38 (9) ◽  
pp. 945-952 ◽  
Author(s):  
Pierre Marsot ◽  
Allan D. Cembella ◽  
Khadija Mouhri
Keyword(s):  
Phaeodactylum Tricornutum ◽  
Inorganic Nitrogen ◽  
Biomass Concentration ◽  
Diffusion Limit ◽  
Active Growth ◽  
Culture Techniques ◽  
Uptake Activity ◽  
Nitrogen Nutrients ◽  
Menten Constant ◽  
Dialysis Culture

The unique conditions associated with discontinuous (batch) dialysis culture of the diatom Phaeodactylum tricornutum elicit different nutritional responses from those observed in nondialysis culture. Simultaneous determinations of the nitrogen biomass concentration and of the nitrogen nutrients (NO3− + NO2−) in the culture chamber, as well as in the seawater nutrient medium at the entrance and exit of the dialyzer, revealed that nitrogen-biomass production in dialysis cultures is achieved mainly (>90%) during postexponential growth, when the concentration of nutrients is limiting (smaller than Michaelis-Menten constant). Almost half of this biomass is produced at the diffusion limit of the apparatus, i.e., when the mass transfer of nutrient substrates, which determines the total uptake activity of the culture, reaches a maximum. In contrast, in nondialysis discontinuous cultures, in which the postexponential growth phase is short, most of the total cellular nitrogen is accumulated during active growth. Certain physiological indices relating to the active uptake and assimilation of inorganic nitrogen are consistent with the different nutritional responses elicited by these two types of culture techniques and explain the high biomass levels obtained in dialysis culture. Key words: dialysis culture, diatom, nitrogen metabolism.

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