23 research outputs found
Emergent Bio-Functional Similarities in a Cortical-Spike-Train-Decoding Spiking Neural Network Facilitate Predictions of Neural Computation
Despite its better bio-plausibility, goal-driven spiking neural network (SNN)
has not achieved applicable performance for classifying biological spike
trains, and showed little bio-functional similarities compared to traditional
artificial neural networks. In this study, we proposed the motorSRNN, a
recurrent SNN topologically inspired by the neural motor circuit of primates.
By employing the motorSRNN in decoding spike trains from the primary motor
cortex of monkeys, we achieved a good balance between classification accuracy
and energy consumption. The motorSRNN communicated with the input by capturing
and cultivating more cosine-tuning, an essential property of neurons in the
motor cortex, and maintained its stability during training. Such
training-induced cultivation and persistency of cosine-tuning was also observed
in our monkeys. Moreover, the motorSRNN produced additional bio-functional
similarities at the single-neuron, population, and circuit levels,
demonstrating biological authenticity. Thereby, ablation studies on motorSRNN
have suggested long-term stable feedback synapses contribute to the
training-induced cultivation in the motor cortex. Besides these novel findings
and predictions, we offer a new framework for building authentic models of
neural computation
Effects of rice or wheat residue retention on the quality of milled japonica rice in a rice–wheat rotation system in China
AbstractIn rice–wheat rotation systems, crop straw is usually retained in the field at land preparation in every, or every other, season. We conducted a 3-year-6-season experiment in the middle–lower Yangtze River Valley to compare the grain qualities of rice under straw retained after single or double seasons per year. Four treatments were designed as: both wheat and rice straw retained (WR), only rice straw retained (R), only wheat straw retained (W), and no straw retained (CK). The varieties were Yangmai 16 wheat and Wuyunjing 23 japonica rice. The results showed contrasting effects of W and R on rice quality. Amylopectin content, peak viscosity, cool viscosity, and breakdown viscosity of rice grain were significantly increased in W compared to the CK, whereas gelatinization temperature, setback viscosity, and protein content significantly decreased. In addition, the effect of WR on rice grain quality was similar to that of W, although soil fertility was enhanced in WR due to straw being retained in two cycles. The differences in protein and starch contents among the treatments might result from soil nitrogen supply. These results indicate that wheat straw retained in the field is more important for high rice quality than rice straw return, and straw from both seasons is recommended for positive effects on soil fertility
Sub-second periodic radio oscillations in a microquasar
Powerful relativistic jets are one of the ubiquitous features of accreting
black holes in all scales. GRS 1915+105 is a well-known fast-spinning
black-hole X-ray binary with a relativistic jet, termed as a ``microquasar'',
as indicated by its superluminal motion of radio emission. It exhibits
persistent x-ray activity over the last 30 years, with quasi-periodic
oscillations of Hz and 34 and 67 Hz in the x-ray band. These
oscillations likely originate in the inner accretion disk, but other origins
have been considered. Radio observations found variable light curves with
quasi-periodic flares or oscillations with periods of minutes.
Here we report two instances of 5 Hz transient periodic oscillation
features from the source detected in the 1.05-1.45 GHz radio band that occurred
in January 2021 and June 2022, respectively. Circular polarization was also
observed during the oscillation phase.Comment: The author version of the article which will appear in Nature on 26
July 2023, 32 pages including the extended data. The online publication
version can be found at the following URL:
https://www.nature.com/articles/s41586-023-06336-
Control of Microcystis aeruginosa TH01109 with batangas mandarin skin and dwarf banana peel: technical note
We studied the inhibitory effects of batangas mandarin skin and dwarf banana peel on Microcystis aeruginosa. In laboratory assays, algal growth was significantly inhibited by the addition of mandarin skin extract (0.1% w/v). When the concentration of mandarin skin increased to 0.5% (w/v), no algal growth was detected, whereas in the presence of banana peel extract (0.5%, w/v) the algal biomass was only slightly suppressed. The results show that mandarin skin has higher anti-algal activity than banana peel. Fresh unprocessed mandarin skin and banana peel showed very effective anti-algal activity. Pre-treatment was not required for their antialgal activity. It is possible that mandarin skin and banana peel might be effective material to control harmful algal blooms.
WaterSA Vol.30 (2) 2004: 279-28
Efficient Synthesis of cis-4-Propylcyclohexanol Using a Mutant Alcohol Dehydrogenase Coupled with Glucose Dehydrogenase
cis-4-Propylcyclohexanol is an important intermediate for synthesizing trans-2-(4-propylcyclohexyl)-1,3-propanediol, which is widely used in the manufacture of liquid crystal displays. In this study, cis-4-propylcyclohexanol was prepared using a mutant alcohol dehydrogenase from Lactobacillus kefir (LK-TADH, A94T/F147L/L199H/A202L) coupled with glucose dehydrogenase. Using the optimal catalytic conditions, 125 g/L (250 g) of 4-propylcyclohexanone was completely transformed after 5 h, and 225.8 g of cis-4-propylcyclohexanol (cis/trans ratio of 99.5:0.5) was obtained through extraction and rotary evaporation at a yield of 90.32%. This study reports a potential method for the green production of cis-4-propylcyclohexanol as the key intermediate of trans-2-(4-propylcyclohexyl)-1,3-propanediol at an industrial level
Efficient Synthesis of <i>cis</i>-4-Propylcyclohexanol Using a Mutant Alcohol Dehydrogenase Coupled with Glucose Dehydrogenase
cis-4-Propylcyclohexanol is an important intermediate for synthesizing trans-2-(4-propylcyclohexyl)-1,3-propanediol, which is widely used in the manufacture of liquid crystal displays. In this study, cis-4-propylcyclohexanol was prepared using a mutant alcohol dehydrogenase from Lactobacillus kefir (LK-TADH, A94T/F147L/L199H/A202L) coupled with glucose dehydrogenase. Using the optimal catalytic conditions, 125 g/L (250 g) of 4-propylcyclohexanone was completely transformed after 5 h, and 225.8 g of cis-4-propylcyclohexanol (cis/trans ratio of 99.5:0.5) was obtained through extraction and rotary evaporation at a yield of 90.32%. This study reports a potential method for the green production of cis-4-propylcyclohexanol as the key intermediate of trans-2-(4-propylcyclohexyl)-1,3-propanediol at an industrial level
MpADC, an l-aspartate-α-decarboxylase, from Myzus persicae, that enables production of β-alanine with high yield by whole-cell enzymatic catalysis
Abstract Background β-Alanine is a precursor of many important pharmaceutical products and food additives, its market demand is continuously increasing nowadays. Whole-cell catalysis relying on the recombinant expression of key β-alanine synthesizing enzymes is an important method to produce β-alanine. Nevertheless, β-alanine synthesizing enzymes found so far have problems including easy inactivation, low expression or poor catalytic activity, and it remains necessary to develop new enzymes. Results Herein, we characterized an l-aspartate-α-decarboxylase, MpADC, from an aphid, Myzus persicae. It showed excellent catalytic activity at pH 6.0–7.5 and 37 °C. With the help of chaperone co-expression and N-terminal engineering guided by AlphaFold2 structure prediction, the expression and catalytic ability of MpADC in Escherichia coli were significantly improved. Using 50 g/L of E. coli cells expressing the MpADC-∆39 variant cultured in a 15-L fermenter, 232.36 g/L of β-alanine was synthesized in 13.5 h, with the average β-alanine yield of 17.22 g/L/h, which is best known so far. Conclusions Our research should facilitate the production of β-alanine in an environment-friendly manner
FULL TIME-SPACE GOVERNANCE STRATEGY AND TECHNOLOGY FOR CROPLAND NON-POINT POLLUTION CONTROL IN CHINA
● Full time-space governance strategy for AGNPS pollution was proposed.● The 4R chain technology system including source reduction, process retention, nutrient reuse and water restoration was reviewed.● The strategy and 4R technology system was successfully applied for AGNPS pollution control at administrative village scale.● Future challenge include the monitoring system, new smart fertilizer and intelligent equipment, governance standards and supportive policies. Ensuring food safety while reducing agricultural non-point source pollution is quite challenging, especially in developing and underdeveloped countries. Effective systematic strategies and comprehensive technologies need to be developed for agricultural non-point source pollution control at the watershed scale to improve surface water quality. In this review, a proposal is made for a full time-space governance strategy that prioritizes source management followed by endpoint water pollution control. The 4R chain technology system is specifically reviewed, including source reduction, process retention, nutrient reuse and water restoration. The 4R chain technology system with the full time-space governance strategy was applied at the scale of an administrative village and proved to be a feasible solution for reducing agricultural non-point source pollution in China. In the future, a monitoring system needs to be established to trace N and P transport. Additionally, new smart fertilizer and intelligent equipment need to be developed, and relevant governance standards and supportive policies need to be set to enhance the efficacy of agricultural non-point source pollution control
Attenuation of potato pathogenicity of <i>Erwinia carotovora</i> by recombinant QsdH- producing <i>E. coli</i>.
<p>1, saline solution; 2, <i>E. coli</i> carrying pGEX-6p-1; 3, <i>E. coli</i> carrying pGEX-6p-<i>qsdH</i>; 4, <i>E. carotovora</i>; 5, mixture of <i>E. carotovora</i> and <i>E. coli</i> carrying pGEX-6p-1; 6, mixture of <i>E. carotovora</i> and <i>E. coli</i> carrying pGEX-6p-<i>qsdH</i>.</p