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1.
Brief Bioinform ; 25(4)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38877888

RESUMO

One of the prevalent chronic inflammatory disorders of the nasal mucosa, allergic rhinitis (AR) has become more widespread in recent years. Acupuncture pterygopalatine ganglion (aPPG) is an emerging alternative therapy that is used to treat AR, but the molecular mechanisms underlying its anti-inflammatory effects are unclear. This work methodically demonstrated the multi-target mechanisms of aPPG in treating AR based on bioinformatics/topology using techniques including text mining, bioinformatics, and network topology, among others. A total of 16 active biomarkers and 108 protein targets related to aPPG treatment of AR were obtained. A total of 345 Gene Ontology terms related to aPPG of AR were identified, and 135 pathways were screened based on Kyoto Encyclopedia of Genes and Genomes analysis. Our study revealed for the first time the multi-targeted mechanism of action of aPPG in the treatment of AR. In animal experiments, aPPG ameliorated rhinitis symptoms in OVA-induced AR rats; decreased serum immunoglobulin E, OVA-sIgE, and substance P levels; elevated serum neuropeptide Y levels; and modulated serum Th1/Th2/Treg/Th17 cytokine expression by a mechanism that may be related to the inhibition of activation of the TLR4/NF-κB/NLRP3 signaling pathway. In vivo animal experiments once again validated the results of the bioinformatics analysis. This study revealed a possible multi-target mechanism of action between aPPG and AR, provided new insights into the potential pathogenesis of AR, and proved that aPPG was a promising complementary alternative therapy for the treatment of AR.


Assuntos
Terapia por Acupuntura , Biologia Computacional , Rinite Alérgica , Rinite Alérgica/terapia , Rinite Alérgica/metabolismo , Animais , Biologia Computacional/métodos , Ratos , Gânglios Parassimpáticos/metabolismo , Masculino , Humanos , Mapas de Interação de Proteínas , Citocinas/metabolismo
2.
Brief Bioinform ; 25(4)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38851299

RESUMO

Protein-protein interactions (PPIs) are the basis of many important biological processes, with protein complexes being the key forms implementing these interactions. Understanding protein complexes and their functions is critical for elucidating mechanisms of life processes, disease diagnosis and treatment and drug development. However, experimental methods for identifying protein complexes have many limitations. Therefore, it is necessary to use computational methods to predict protein complexes. Protein sequences can indicate the structure and biological functions of proteins, while also determining their binding abilities with other proteins, influencing the formation of protein complexes. Integrating these characteristics to predict protein complexes is very promising, but currently there is no effective framework that can utilize both protein sequence and PPI network topology for complex prediction. To address this challenge, we have developed HyperGraphComplex, a method based on hypergraph variational autoencoder that can capture expressive features from protein sequences without feature engineering, while also considering topological properties in PPI networks, to predict protein complexes. Experiment results demonstrated that HyperGraphComplex achieves satisfactory predictive performance when compared with state-of-art methods. Further bioinformatics analysis shows that the predicted protein complexes have similar attributes to known ones. Moreover, case studies corroborated the remarkable predictive capability of our model in identifying protein complexes, including 3 that were not only experimentally validated by recent studies but also exhibited high-confidence structural predictions from AlphaFold-Multimer. We believe that the HyperGraphComplex algorithm and our provided proteome-wide high-confidence protein complex prediction dataset will help elucidate how proteins regulate cellular processes in the form of complexes, and facilitate disease diagnosis and treatment and drug development. Source codes are available at https://github.com/LiDlab/HyperGraphComplex.


Assuntos
Biologia Computacional , Mapeamento de Interação de Proteínas , Biologia Computacional/métodos , Mapeamento de Interação de Proteínas/métodos , Proteínas/metabolismo , Proteínas/química , Algoritmos , Mapas de Interação de Proteínas , Bases de Dados de Proteínas , Humanos , Análise de Sequência de Proteína/métodos , Sequência de Aminoácidos
3.
Stat Appl Genet Mol Biol ; 23(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38363177

RESUMO

Developments in biotechnologies enable multi-platform data collection for functional genomic units apart from the gene. Profiling of non-coding microRNAs (miRNAs) is a valuable tool for understanding the molecular profile of the cell, both for canonical functions and malignant behavior due to complex diseases. We propose a graphical mixed-effects statistical model incorporating miRNA-gene target relationships. We implement an integrative pathway analysis that leverages measurements of miRNA activity for joint analysis with multimodal observations of gene activity including gene expression, methylation, and copy number variation. We apply our analysis to a breast cancer dataset, and consider differential activity in signaling pathways across breast tumor subtypes. We offer discussion of specific signaling pathways and the effect of miRNA integration, as well as publish an interactive data visualization to give public access to the results of our analysis.


Assuntos
Neoplasias da Mama , MicroRNAs , Humanos , Feminino , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias da Mama/metabolismo , Variações do Número de Cópias de DNA , Perfilação da Expressão Gênica , Metilação de DNA/genética , Expressão Gênica , Regulação Neoplásica da Expressão Gênica
4.
J Neurosci ; 43(48): 8140-8156, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-37758476

RESUMO

Although much is known about how single neurons in the hippocampus represent an animal's position, how circuit interactions contribute to spatial coding is less well understood. Using a novel statistical estimator and theoretical modeling, both developed in the framework of maximum entropy models, we reveal highly structured CA1 cell-cell interactions in male rats during open field exploration. The statistics of these interactions depend on whether the animal is in a familiar or novel environment. In both conditions the circuit interactions optimize the encoding of spatial information, but for regimes that differ in the informativeness of their spatial inputs. This structure facilitates linear decodability, making the information easy to read out by downstream circuits. Overall, our findings suggest that the efficient coding hypothesis is not only applicable to individual neuron properties in the sensory periphery, but also to neural interactions in the central brain.SIGNIFICANCE STATEMENT Local circuit interactions play a key role in neural computation and are dynamically shaped by experience. However, measuring and assessing their effects during behavior remains a challenge. Here, we combine techniques from statistical physics and machine learning to develop new tools for determining the effects of local network interactions on neural population activity. This approach reveals highly structured local interactions between hippocampal neurons, which make the neural code more precise and easier to read out by downstream circuits, across different levels of experience. More generally, the novel combination of theory and data analysis in the framework of maximum entropy models enables traditional neural coding questions to be asked in naturalistic settings.


Assuntos
Região CA1 Hipocampal , Hipocampo , Ratos , Masculino , Animais , Região CA1 Hipocampal/fisiologia , Neurônios/fisiologia , Rede Nervosa/fisiologia
5.
Hum Brain Mapp ; 45(2): e26587, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38339903

RESUMO

Recent years have seen growing interest in characterizing the properties of regional brain dynamics and their relationship to other features of brain structure and function. In particular, multiple studies have observed regional differences in the "timescale" over which activity fluctuates during periods of quiet rest. In the cerebral cortex, these timescales have been associated with both local circuit properties as well as patterns of inter-regional connectivity, including the extent to which each region exhibits widespread connectivity to other brain areas. In the current study, we build on prior observations of an association between connectivity and dynamics in the cerebral cortex by investigating the relationship between BOLD fMRI timescales and the modular organization of structural and functional brain networks. We characterize network community structure across multiple scales and find that longer timescales are associated with greater within-community functional connectivity and diverse structural connectivity. We also replicate prior observations of a positive correlation between timescales and structural connectivity degree. Finally, we find evidence for preferential functional connectivity between cortical areas with similar timescales. We replicate these findings in an independent dataset. These results contribute to our understanding of functional brain organization and structure-function relationships in the human brain, and support the notion that regional differences in cortical dynamics may in part reflect the topological role of each region within macroscale brain networks.


Assuntos
Encéfalo , Córtex Cerebral , Humanos , Encéfalo/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética , Descanso , Rede Nervosa/diagnóstico por imagem
6.
Brief Bioinform ; 23(3)2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35229103

RESUMO

Coronavirus disease 2019 (COVID-19) is a global pandemic and there is an urgent need to discover the therapy for COVID-19. In our original article, we first obtained the target proteins of acupuncture and related target genes of COVID-19 by searching English and Chinese databases, then Gene Ontology biological processes and enrichment analysis were performed on the overlapping targets of acupuncture with COVID-19. Moreover, the compound-target and compound-disease-target network was constructed. This is an innovative attempt to predict the potential benefits of acupuncture treatment for COVID-19. In this letter, we answered reader Zheng's comments.


Assuntos
Terapia por Acupuntura , Acupuntura , COVID-19 , COVID-19/terapia , Biologia Computacional , Ontologia Genética , Humanos
7.
Brief Bioinform ; 23(1)2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-34601563

RESUMO

Coronavirus disease 2019 (COVID-19) has attracted research interests from all fields. Phylogenetic and social network analyses based on connectivity between either COVID-19 patients or geographic regions and similarity between syndrome coronavirus 2 (SARS-CoV-2) sequences provide unique angles to answer public health and pharmaco-biological questions such as relationships between various SARS-CoV-2 mutants, the transmission pathways in a community and the effectiveness of prevention policies. This paper serves as a systematic review of current phylogenetic and social network analyses with applications in COVID-19 research. Challenges in current phylogenetic network analysis on SARS-CoV-2 such as unreliable inferences, sampling bias and batch effects are discussed as well as potential solutions. Social network analysis combined with epidemiology models helps to identify key transmission characteristics and measure the effectiveness of prevention and control strategies. Finally, future new directions of network analysis motivated by COVID-19 data are summarized.


Assuntos
COVID-19 , Modelos Biológicos , Pandemias , Filogenia , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/imunologia , COVID-19/transmissão , Humanos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade
8.
Cereb Cortex ; 33(17): 9867-9876, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37415071

RESUMO

Menstrually-related migraine (MM) is a primary migraine in women of reproductive age. The underlying neural mechanism of MM was still unclear. In this study, we aimed to reveal the case-control differences in network integration and segregation for the morphometric similarity network of MM. Thirty-six patients with MM and 29 healthy females were recruited and underwent MRI scanning. The morphometric features were extracted in each region to construct the single-subject interareal cortical connection using morphometric similarity. The network topology characteristics, in terms of integration and segregation, were analyzed. Our results revealed that, in the absence of morphology differences, disrupted cortical network integration was found in MM patients compared to controls. The patients with MM showed a decreased global efficiency and increased characteristic path length compared to healthy controls. Regional efficiency analysis revealed the decreased efficiency in the left precentral gyrus and bilateral superior temporal gyrus contributed to the decreased network integration. The increased nodal degree centrality in the right pars triangularis was positively associated with the attack frequency in MM. Our results suggested MM would reorganize the morphology in the pain-related brain regions and reduce the parallel information processing capacity of the brain.


Assuntos
Encéfalo , Transtornos de Enxaqueca , Humanos , Feminino , Encéfalo/diagnóstico por imagem , Transtornos de Enxaqueca/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Córtex Pré-Frontal , Dor
9.
Cereb Cortex ; 33(13): 8594-8604, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37106566

RESUMO

Brain dynamics can be modeled by a sequence of transient, nonoverlapping patterns of quasi-stable electrical potentials named "microstates." While electroencephalographic (EEG) microstates among patients with chronic pain remained inconsistent in the literature, this study characterizes the temporal dynamics of EEG microstates among healthy individuals during experimental sustained pain. We applied capsaicin (pain condition) or control (no-pain condition) cream to 58 healthy participants in different sessions and recorded resting-state EEG 15 min after application. We identified 4 canonical microstates (A-D) that are related to auditory, visual, salience, and attentional networks. Microstate C had less occurrence, as were bidirectional transitions between microstate C and microstates A and B during sustained pain. In contrast, sustained pain was associated with more frequent and longer duration of microsite D, as well as more bidirectional transitions between microstate D and microstates A and B. Microstate D duration positively correlated with intensity of ongoing pain. Sustained pain improved global integration within microstate C functional network, but weakened global integration and efficiency within microstate D functional network. These results suggest that sustained pain leads to an imbalance between processes that load on saliency (microstate C) and processes related to switching and reorientation of attention (microstate D).


Assuntos
Encéfalo , Eletroencefalografia , Humanos , Mapeamento Encefálico/métodos , Atenção , Dor
10.
Proc Natl Acad Sci U S A ; 118(5)2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33495341

RESUMO

Over one third of the estimated 3 million people with epilepsy in the United States are medication resistant. Responsive neurostimulation from chronically implanted electrodes provides a promising treatment alternative to resective surgery. However, determining optimal personalized stimulation parameters, including when and where to intervene to guarantee a positive patient outcome, is a major open challenge. Network neuroscience and control theory offer useful tools that may guide improvements in parameter selection for control of anomalous neural activity. Here we use a method to characterize dynamic controllability across consecutive effective connectivity (EC) networks based on regularized partial correlations between implanted electrodes during the onset, propagation, and termination regimes of 34 seizures. We estimate regularized partial correlation adjacency matrices from 1-s time windows of intracranial electrocorticography recordings using the Graphical Least Absolute Shrinkage and Selection Operator (GLASSO). Average and modal controllability metrics calculated from each resulting EC network track the time-varying controllability of the brain on an evolving landscape of conditionally dependent network interactions. We show that average controllability increases throughout a seizure and is negatively correlated with modal controllability throughout. Our results support the hypothesis that the energy required to drive the brain to a seizure-free state from an ictal state is smallest during seizure onset, yet we find that applying control energy at electrodes in the seizure onset zone may not always be energetically favorable. Our work suggests that a low-complexity model of time-evolving controllability may offer insights for developing and improving control strategies targeting seizure suppression.


Assuntos
Progressão da Doença , Rede Nervosa/patologia , Convulsões/patologia , Epilepsia/patologia , Humanos , Fatores de Tempo
11.
Parasitol Res ; 123(2): 128, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38332167

RESUMO

The study of host-parasite interactions is essential to understand the role of each host species in the parasitic transmission cycles in a given community. The use of ecological network highlights the patterns of interactions between hosts and parasites, allowing us to evaluate the underlying structural features and epidemiological roles of different species within this context. Through network analysis, we aimed to understand the epidemiological roles of mammalian hosts species (n = 67) and their parasites (n = 257) in the Pantanal biome. Our analysis revealed a modular pattern within the network, characterized by 14 distinct modules, as well as nestedness patterns within these modules. Some key nodes, such as the multi-host parasites Trypanosoma cruzi and T. evansi, connect different modules and species. These central nodes showed us that various hosts species, including those with high local abundances, contribute to parasite maintenance. Ectoparasites, such as ticks and fleas, exhibit connections that reflect their roles as vectors of certain parasites. Overall, our findings contribute to a comprehensive understanding of the structure of host-parasite interactions in the Pantanal ecosystem, highlighting the importance of network analysis as a tool to identifying the main transmission routes and maintenance of parasites pathways. Such insights are valuable for parasitic disease control and prevention strategies and shed light on the broader complexities of ecological communities.


Assuntos
Parasitos , Sifonápteros , Animais , Ecossistema , Interações Hospedeiro-Parasita , Mamíferos/parasitologia
12.
Int J Mol Sci ; 25(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38473922

RESUMO

Load-bearing biological tissues, such as cartilage and muscles, exhibit several crucial properties, including high elasticity, strength, and recoverability. These characteristics enable these tissues to endure significant mechanical stresses and swiftly recover after deformation, contributing to their exceptional durability and functionality. In contrast, while hydrogels are highly biocompatible and hold promise as synthetic biomaterials, their inherent network structure often limits their ability to simultaneously possess a diverse range of superior mechanical properties. As a result, the applications of hydrogels are significantly constrained. This article delves into the design mechanisms and mechanical properties of various tough hydrogels and investigates their applications in tissue engineering, flexible electronics, and other fields. The objective is to provide insights into the fabrication and application of hydrogels with combined high strength, stretchability, toughness, and fast recovery as well as their future development directions and challenges.


Assuntos
Materiais Biocompatíveis , Hidrogéis , Hidrogéis/química , Materiais Biocompatíveis/química , Engenharia Tecidual , Elasticidade , Cartilagem
13.
Angew Chem Int Ed Engl ; 63(15): e202400475, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38279903

RESUMO

Porous organic salts (POSs) are organic porous materials assembled via charge-assisted hydrogen bonds between strong acids and bases such as sulfonic acids and amines. To diversify the network topology of POSs and extend its functions, this study focused on using 4,4',4'',4'''-(9,9'-spirobi[fluorene]-2,2',7,7'-tetrayl)tetrabenzenesulfonic acid (spiroBPS), which is a tetrasulfonic acid comprising a square planar skeleton. The POS consisting of spiroBPS and triphenylmethylamine (TPMA) (spiroBPS/TPMA) was constructed from the two-fold interpenetration of an orthogonal network with pts topology, which has not been reported in conventional POSs, owing to the shape of the spirobifluorene backbone. Furthermore, combining tris(4-chlorophenyl)methylamine (TPMA-Cl) and tris(4-bromophenyl)methylamine (TPMA-Br), which are bulkier than TPMA owing to the introduction of halogens at the p-position of the phenyl groups with spiroBPS allows us to construct novel POSs (spiroBPS/TPMA-Cl and spiroBPS/TPMA-Br). These POSs were constructed from a chiral helical network with pth topology, which was induced by the steric hindrance between the halogens and the curved fluorene skeleton. Moreover, spiroBPS/TPMA-Cl with pth topology exhibited circularly polarized luminescence (CPL) in the solid state, which has not been reported in hydrogen-bonded organic frameworks (HOFs).

14.
Hum Brain Mapp ; 44(11): 4225-4238, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37232486

RESUMO

Tourette syndrome (TS) is a neuropsychiatric disorder characterized by motor and phonic tics, which several different theories, such as basal ganglia-thalamo-cortical loop dysfunction and amygdala hypersensitivity, have sought to explain. Previous research has shown dynamic changes in the brain prior to tic onset leading to tics, and this study aims to investigate the contribution of network dynamics to them. For this, we have employed three methods of functional connectivity to resting-state fMRI data - namely the static, the sliding window dynamic and the ICA based estimated dynamic; followed by an examination of the static and dynamic network topological properties. A leave-one-out (LOO-) validated regression model with LASSO regularization was used to identify the key predictors. The relevant predictors pointed to dysfunction of the primary motor cortex, the prefrontal-basal ganglia loop and amygdala-mediated visual social processing network. This is in line with a recently proposed social decision-making dysfunction hypothesis, opening new horizons in understanding tic pathophysiology.


Assuntos
Tiques , Síndrome de Tourette , Humanos , Tiques/diagnóstico por imagem , Síndrome de Tourette/diagnóstico por imagem , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Gânglios da Base
15.
Hum Brain Mapp ; 44(5): 1868-1875, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36478470

RESUMO

Visual snow syndrome (VSS) is a neurological disorder characterized by a range of continuous visual disturbances. Little is known about the functional pathological mechanisms underlying VSS and their effect on brain network topology, studied using high-resolution resting-state (RS) 7 T MRI. Forty VSS patients and 60 healthy controls underwent RS MRI. Functional connectivity matrices were calculated, and global efficiency (network integration), modularity (network segregation), local efficiency (LE, connectedness neighbors) and eigenvector centrality (significance node in network) were derived using a dynamic approach (temporal fluctuations during acquisition). Network measures were compared between groups, with regions of significant difference correlated with known aberrant ocular motor VSS metrics (shortened latencies and higher number of inhibitory errors) in VSS patients. Lastly, nodal co-modularity, a binary measure of node pairs belonging to the same module, was studied. VSS patients had lower modularity, supramarginal centrality and LE dynamics of multiple (sub)cortical regions, centered around occipital and parietal lobules. In VSS patients, lateral occipital cortex LE dynamics correlated positively with shortened prosaccade latencies (p = .041, r = .353). In VSS patients, occipital, parietal, and motor nodes belonged more often to the same module and demonstrated lower nodal co-modularity with temporal and frontal regions. This study revealed reduced dynamic variation in modularity and local efficiency strength in the VSS brain, suggesting that brain network dynamics are less variable in terms of segregation and local clustering. Further investigation of these changes could inform our understanding of the pathogenesis of the disorder and potentially lead to treatment strategies.


Assuntos
Encéfalo , Transtornos da Visão , Humanos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Lobo Occipital , Lobo Parietal
16.
Brief Bioinform ; 22(5)2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-33866350

RESUMO

Acupuncture is an important part of Chinese medicine that has been widely used in the treatment of inflammatory diseases. During the coronavirus disease 2019 (COVID-19) epidemic, acupuncture has been used as a complementary treatment for COVID-19 in China. However, the underlying mechanism of acupuncture treatment of COVID-19 remains unclear. Based on bioinformatics/topology, this paper systematically revealed the multi-target mechanisms of acupuncture therapy for COVID-19 through text mining, bioinformatics, network topology, etc. Two active compounds produced after acupuncture and 180 protein targets were identified. A total of 522 Gene Ontology terms related to acupuncture for COVID-19 were identified, and 61 pathways were screened based on the Kyoto Encyclopedia of Genes and Genomes. Our findings suggested that acupuncture treatment of COVID-19 was associated with suppression of inflammatory stress, improving immunity and regulating nervous system function, including activation of neuroactive ligand-receptor interaction, calcium signaling pathway, cancer pathway, viral carcinogenesis, Staphylococcus aureus infection, etc. The study also found that acupuncture may have additional benefits for COVID-19 patients with cancer, cardiovascular disease and obesity. Our study revealed for the first time the multiple synergistic mechanisms of acupuncture on COVID-19. Acupuncture may play an active role in the treatment of COVID-19 and deserves further promotion and application. These results may help to solve this pressing problem currently facing the world.


Assuntos
Acupuntura , COVID-19/terapia , Biologia Computacional/métodos , COVID-19/fisiopatologia , COVID-19/virologia , Humanos , SARS-CoV-2/isolamento & purificação , Resultado do Tratamento
17.
Phys Biol ; 20(4)2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37190961

RESUMO

The network-shaped body plan distinguishes the unicellular slime mouldPhysarum polycephalumin body architecture from other unicellular organisms. Yet, network-shaped body plans dominate branches of multi-cellular life such as in fungi. What survival advantage does a network structure provide when facing a dynamic environment with adverse conditions? Here, we probe how network topology impactsP. polycephalum's avoidance response to an adverse blue light. We stimulate either an elongated, I-shaped amoeboid or a Y-shaped networked specimen and subsequently quantify the evacuation process of the light-exposed body part. The result shows that Y-shaped specimen complete the avoidance retraction in a comparable time frame, even slightly faster than I-shaped organisms, yet, at a lower almost negligible increase in migration velocity. Contraction amplitude driving mass motion is further only locally increased in Y-shaped specimen compared to I-shaped-providing further evidence that Y-shaped's avoidance reaction is energetically more efficient than in I-shaped amoeboid organisms. The difference in the retraction behaviour suggests that the complexity of network topology provides a key advantage when encountering adverse environments. Our findings could lead to a better understanding of the transition from unicellular to multicellularity.


Assuntos
Physarum polycephalum , Physarum polycephalum/fisiologia , Modelos Biológicos
18.
Environ Res ; 219: 115123, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36549490

RESUMO

Under current climatic conditions, developing eco-friendly and climate-smart fertilizers has become increasingly important.The co-application of biochar and compost on agricultural soils has received considerable attention recently.Unfortunately, little is known about its effects on specific microbial taxa involved in carbon and nitrogen transformation in the soil.Herein, we report the efficacy of applying biochar-based amendments on soil physicochemical indices, enzymatic activity, functional genes, bacterial community, and their network patterns in corn rhizosphere at seedling (SS), flowering (FS), and maturity (MS) stages.The applied treatments were: compost alone (COM), biochar alone (BIOC), composted biochar (CMB), fortified compost (CMWB), and the control (no fertilizer (CNTRL).The non-metric multidimensional scaling (NMDS) indicated total nitrogen (TN), pH, NO3--N, urease, protease, and microbial biomass C (MBC) as the dominant environmental factors driving soil bacteria in this study.The dominant N mediating genes belonged to nitrate reductase (narG) and nitronate monooxygenase (amo), while beta-galactosidase, catalase, and alpha-amylase were the dominant genes observed relating to C cycling.Interestingly, the abundance of these genes was higher in COM, CMWB, and CMB compared with the CNTRL and BIOC treatments.The bacteria network properties of CWMB and CMB indicated robust niche overlap associated with high cross-feeding between bacterial communities compared to other treatments.Path and stepwise regression analyses revealed norank_Reyranellaceae and Sphingopyxis in CMWB as the major bacterial genera and the major predictive indices mediating soil organic C (SOC), NH4+-N, NO3--N, and TN transformation.Overall, biochar with compost amendments improved soil nutrient conditions, regulated the composition of the bacterial community, and benefited C/N cycling in the soil ecosystem.


Assuntos
Compostagem , Microbiota , Carbono , Zea mays , Nitrogênio/análise , Solo/química , Bactérias/genética , Fertilizantes/análise , Microbiologia do Solo
19.
Sensors (Basel) ; 23(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36679723

RESUMO

The recent development of unmanned aerial vehicle (UAV) technology has shown the possibility of using UAVs in many research and industrial fields. One of them is for UAVs moving in swarms to provide wireless networks in environments where there is no network infrastructure. Although this method has the advantage of being able to provide a network quickly and at a low cost, it may cause scalability problems in multi-hop connectivity and UAV control when trying to cover a large area. Therefore, as more UAVs are used to form drone networks, the problem of efficiently controlling the network topology must be solved. To solve this problem, we propose a topology control system for drone networks, which analyzes relative positions among UAVs within a swarm, then optimizes connectivity among them in perspective of both interference and energy consumption, and finally reshapes a logical structure of drone networks by choosing neighbors per UAV and mapping data flows over them. The most important function in the scheme is the connectivity optimization because it should be adaptively conducted according to the dynamically changing complex network conditions, which includes network characteristics such as user density and UAV characteristics such as power consumption. Since neither a simple mathematical framework nor a network simulation tool for optimization can be a solution, we need to resort to reinforcement learning, specifically DDPG, with which each UAV can adjust its connectivity to other drones. In addition, the proposed system minimizes the learning time by flexibly changing the number of steps used for parameter learning according to the deployment of new UAVs. The performance of the proposed system was verified through simulation experiments and theoretical analysis on various topologies consisting of multiple UAVs.


Assuntos
Aprendizagem , Dispositivos Aéreos não Tripulados , Simulação por Computador , Indústrias , Tecnologia
20.
J Environ Manage ; 346: 119015, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37738718

RESUMO

The interest in wastewater monitoring is always growing, with applications mainly aimed at detection of pollutants and at the environmental epidemiological surveillance. However, it often happens that the strategies proposed to manage these problems are inapplicable due to the lack of information on the hydraulics of the systems. To overcome this problem, the present paper develops and proposes a topological backtracking strategy for the optimal monitoring of sewer networks, which acts by subrogating the hydraulic information with the geometric ones, e.g., diameter and slope, thus not requiring any hydraulic simulation. The topological backtracking approach aims at evaluating an impact coefficient for each node of the network used to face with the problems of sensor location and network coverage for purposes related to the spread of contaminants and pathogens. Finally, the positioning of the sensors for each monitoring scheme is addressed by a priority rank, based on the efficiency of each sensor in terms of network coverage with respect to a specific weight (e.g., length, flow). The main goal is to design a monitoring scheme that provide the required coverage of the network by minimizing the number of sensors with respect to specific measurement threshold value. The results show the effectiveness of the strategy in supporting the optimal design with the topological-based backtracking approach without the necessity of performing hydraulic simulations, with great advantage in terms of required data and computational time.

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