109 research outputs found
Natural anti-phytopathogenic fungi compound phenol, 2, 4-bis (1, 1-dimethylethyl) from Pseudomonas fluorescens TL-1
A strain was isolated from tobacco phylloplane and preliminarily identified as Pseudomonas fluorescens TL-1, which had the visible inhibition against ten plant pathogenic fungi, viz., Curvularia lunata, Bipolaris maydis, Valsa mali, Rhizoctonia solani, Colletotrichum gloeosporioides, Sclerotinia sclerotiorum, Botrytis cinerea, Alternaria alternate, Fusarium oxysporum and Verticillium dahlia in dual culture experiments. The ethyl acetate extract of nutrient broth seeded with Pseudomonas fluorescens TL-1 suspension was separated into fifty-nine fractions by the Sephadex LH-20 column and the antifungal activity of each fraction was tested with paper disc diffusion method against Curvularia lunata. The results showed that fraction 1 to 3 had the strongest inhibitory effects on Curvularia lunata. Furthermore, GC/MS analysis of the constituents of fraction 1 to 59 confirmed that phenol, 2, 4-bis (1, 1-dimethylethyl) was the active compound for the antifungal activity from Pseudomonas fluorescens TL-1
FishMOT: A Simple and Effective Method for Fish Tracking Based on IoU Matching
The tracking of various fish species plays a profoundly significant role in
understanding the behavior of individual fish and their groups. Present
tracking methods suffer from issues of low accuracy or poor robustness. In
order to address these concerns, this paper proposes a novel tracking approach,
named FishMOT (Fish Multiple Object Tracking). This method combines object
detection techniques with the IoU matching algorithm, thereby achieving
efficient, precise, and robust fish detection and tracking. Diverging from
other approaches, this method eliminates the need for multiple feature
extractions and identity assignments for each individual, instead directly
utilizing the output results of the detector for tracking, thereby
significantly reducing computational time and storage space. Furthermore, this
method imposes minimal requirements on factors such as video quality and
variations in individual appearance. As long as the detector can accurately
locate and identify fish, effective tracking can be achieved. This approach
enhances robustness and generalizability. Moreover, the algorithm employed in
this method addresses the issue of missed detections without relying on complex
feature matching or graph optimization algorithms. This contributes to improved
accuracy and reliability. Experimental trials were conducted in the open-source
video dataset provided by idtracker.ai, and comparisons were made with
state-of-the-art detector-based multi-object tracking methods. Additionally,
comparisons were made with idtracker.ai and TRex, two tools that demonstrate
exceptional performance in the field of animal tracking. The experimental
results demonstrate that the proposed method outperforms other approaches in
various evaluation metrics, exhibiting faster speed and lower memory
requirements. The source codes and pre-trained models are available at:
https://github.com/gakkistar/FishMO
Plant microRNAs: Biogenesis, Homeostasis, and Degradation
MicroRNAs (miRNAs), a class of endogenous, tiny, non-coding RNAs, are master regulators of gene expression among most eukaryotes. Intracellular miRNA abundance is regulated under multiple levels of control including transcription, processing, RNA modification, RNA-induced silencing complex (RISC) assembly, miRNA-target interaction, and turnover. In this review, we summarize our current understanding of the molecular components and mechanisms that influence miRNA biogenesis, homeostasis, and degradation in plants. We also make comparisons with findings from other organisms where necessary
LightSpeed: Light and Fast Neural Light Fields on Mobile Devices
Real-time novel-view image synthesis on mobile devices is prohibitive due to
the limited computational power and storage. Using volumetric rendering
methods, such as NeRF and its derivatives, on mobile devices is not suitable
due to the high computational cost of volumetric rendering. On the other hand,
recent advances in neural light field representations have shown promising
real-time view synthesis results on mobile devices. Neural light field methods
learn a direct mapping from a ray representation to the pixel color. The
current choice of ray representation is either stratified ray sampling or
Plucker coordinates, overlooking the classic light slab (two-plane)
representation, the preferred representation to interpolate between light field
views. In this work, we find that using the light slab representation is an
efficient representation for learning a neural light field. More importantly,
it is a lower-dimensional ray representation enabling us to learn the 4D ray
space using feature grids which are significantly faster to train and render.
Although mostly designed for frontal views, we show that the light-slab
representation can be further extended to non-frontal scenes using a
divide-and-conquer strategy. Our method offers superior rendering quality
compared to previous light field methods and achieves a significantly improved
trade-off between rendering quality and speed.Comment: Project Page: http://lightspeed-r2l.github.io/ . Add camera ready
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Formulation Optimization and Quality Analysis of Moringa Seed Multigrain Bread Based on Fuzzy Mathematics
In order to meet people's demand for nutritious food, bread was taken as a carrier, and fuzzy mathematics and sensory evaluation method were adopted. Based on sensory score, the recipe of Moringa seed multigrain bread was optimized by single factor and orthogonal experiment. On this basis, the physicochemical and bacteriostatic characteristics of Moringa seed multigrain bread were analyzed. The results showed that the order of Moringa seed multigrain bread was as follows: Moringa seed supplemental level>Job's barley supplemental level>red bean supplemental level>sweet potato supplemental level. The optimal formula of moringa seed multigrain bread was as follows: Milk content 34%, butter content 7.5%, whole egg content 40%, yeast content 0.8%, white sugar content 5.1%, Moringa seed content 2.6%, sweet potato content 2.1%, red bean content 1.6%, and Job's barley content 2.1%. The fuzzy mathematical sensory score of the bread under this formula was the highest (86.35), and the bread was full flavour, soft and palpable. The peroxide value, acid value and total number of colonies were all in line with national standards, and the protein content was 5.6 g/100 g higher than that of ordinary bread. After storage for 5 days, the increase of acid value of Moringa seed multigrain bread (25%) was less than that of regular bread (40%), and the increase of peroxide value (20%) was also lower than that of regular bread (73.7%). Meanwhile, the number of bacterial colonies in regular bread was 3 times higher than that in Moringa seed multigrain bread, which indicated that Moringa seed multigrain bread had certain rancidity delay and antibacterial effect. The results of this study could provide useful reference for the development of Moringa seed multigrain products
Verrucisidinol and Verrucosidinol Acetate, Two Pyrone-Type Polyketides Isolated from a Marine Derived Fungus, Penicillium aurantiogriseum
The new secondary metabolites verrucosidinol (1) and its derivative verrucosidinol acetate (2), together with a potent neurotoxin verrucosidin (3), a congener norverrucosidin (4) and a mixture of two known phytotoxic metabolites terrestric acids (5 and 6), were isolated from the marine derived fungus Penicillium aurantiogriseum. Verrucosidinol has a ring-opened ethylene oxide moiety in the polyene α-pyrone skeleton, and verrucosidinol acetate is its acetate derivative. The chemical structures were determined by comparing with literature data and a combination of spectroscopic techniques, including high resolution mass spectrum and two-dimentional nuclear magnetic resonance spectroscopic analysis
Effect of ply angle on nonlinear static aeroelasticity of high-aspect-ratio composite wing
In order to reduce the weight and improve aerodynamic characteristics, the new aircraft generally adopts lightweight composite materials and high-aspect-ratio layout. Such the structural layout aircraft will produce large nonlinear aeroelastic deformation under the action of aerodynamic loads. Due to the anisotropy of the composite, the composite ply angle of wing skin has a great influence on the elastic deformation of the high-aspect-ratio wing. In order to study the influence of the ply angle on the nonlinear static aeroelastic wing deformation, based on CFD/CSD unidirectional fluid-solid coupling, the structural deformation and stress of high-aspect-ratio composite wing were numerically solved. The wing deformation along the lift direction was taken as the optimization target. The structure strength was taken as the constraint. The ply angle for the composite skin of the high-aspect-ratio composite wing was optimized by the Screening method. The optimization results show the nonlinear static aeroelastic deformation of the wing in the lift direction is reduced by 39.1Â %. The maximum stress of the wing beam and rib is reduced by 39.0Â %. The maximum Tsai-Wu failure factor of the wing skin is reduced by 47.1Â %
Quadruply-labeled serum albumin as a biodegradable nanosensor for simultaneous fluorescence imaging of intracellular pH values, oxygen and temperature
The construction of multiple fluorescent nanosensors for intracellular studies is a challenging task because spectral overlap of indicator probes can lead to cross-talk and mutual interference. This work describes biodegradable nanosensors that can simultaneously measure three intracellular parameters (temperature, pH and oxygen concentration). Bovine serum albumin (BSA) is selected as the scaffold to construct the triple nanosensor by covalent immobilization four fluorophores on BSA. The following luminophores were used: (a) fluorescein as a probe for pH values, (b) a platinum(II) porphyrin complex for oxygen; (c) a europium(III) clathrate complex for temperature, and (d) a rhodamine B as a reference dye. The nanoparticles have a size of 20nm and show excellent biocompatibility and good brightness. The nanosensors were used for ratiometric imaging of intracellular pH values, oxygen and temperature in HeLa cells. The triple nanosensor responds reversibly and this can be used for real-time tracing of these key parameters. Owing to their biodegradable feature, the use of this kind of triple nanosensor reduce the stress on cellular activities because less nanosensors can be used to gather the total information
Biomimetic nanotherapies: red blood cell based core-shell structured nanocomplexes for atherosclerosis management
Cardiovascular disease is the leading cause of mortality worldwide. Atherosclerosis, one of the most common forms of the disease, is characterized by a gradual formation of atherosclerotic plaque, hardening, and narrowing of the arteries. Nanomaterials can serve as powerful delivery platforms for atherosclerosis treatment. However, their therapeutic efficacy is substantially limited in vivo due to nonspecific clearance by the mononuclear phagocytic system. In order to address this limitation, rapamycin (RAP)âloaded poly(lacticâcoâglycolic acid) (PLGA) nanoparticles are cloaked with the cell membrane of red blood cells (RBCs), creating superior nanocomplexes with a highly complex functionalized bioâinterface. The resulting biomimetic nanocomplexes exhibit a wellâdefined âcoreâshellâ structure with favorable hydrodynamic size and negative surface charge. More importantly, the biomimetic nature of the RBC interface results in less macrophageâmediated phagocytosis in the blood and enhanced accumulation of nanoparticles in the established atherosclerotic plaques, thereby achieving targeted drug release. The biomimetic nanocomplexes significantly attenuate the progression of atherosclerosis. Additionally, the biomimetic nanotherapy approach also displays favorable safety properties. Overall, this study demonstrates the therapeutic advantages of biomimetic nanotherapy for atherosclerosis treatment, which holds considerable promise as a new generation of drug delivery system for safe and efficient management of atherosclerosis
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