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1.
J Mater Chem B ; 12(25): 6242-6256, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38842217

RESUMO

Designing artificial nano-enzymes for scavenging reactive oxygen species (ROS) in chondrocytes (CHOs) is considered the most feasible pathway for the treatment of osteoarthritis (OA). However, the accumulation of ROS due to the amount of nano-enzymatic catalytic site exposure and insufficient oxygen supply seriously threatens the clinical application of this therapy. Although metal-organic framework (MOF) immobilization of artificial nano-enzymes to enhance active site exposure has been extensively studied, artificial nano-enzymes/MOFs for ROS scavenging in OA treatment are still lacking. In this study, a biocompatible lubricating hydrogel-loaded iron-doped zeolitic imidazolate framework-8 (Fe/ZIF-8/Gel) centrase was engineered to scavenge endogenous overexpressed ROS synergistically generating dissolved oxygen and enhancing sustained lubrication for CHOs as a ternary artificial nano-enzyme. This property enabled the nano-enzymatic hydrogels to mitigate OA hypoxia and inhibit oxidative stress damage successfully. Ternary strategy-based therapies show excellent cartilage repair in vivo. The experimental results suggest that nano-enzyme-enhanced lubricating hydrogels are a potentially effective OA treatment and a novel strategy.


Assuntos
Condrócitos , Hidrogéis , Espécies Reativas de Oxigênio , Hidrogéis/química , Hidrogéis/farmacologia , Animais , Condrócitos/metabolismo , Condrócitos/efeitos dos fármacos , Condrócitos/citologia , Espécies Reativas de Oxigênio/metabolismo , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Osteoartrite/tratamento farmacológico , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Cartilagem/efeitos dos fármacos , Cartilagem/metabolismo , Tamanho da Partícula , Humanos , Zeolitas/química
2.
Mitochondrial DNA B Resour ; 9(6): 707-710, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38873279

RESUMO

The complete mitochondrial genome of the Zaomma eriococci (Ferrière, 1955) (Hymenoptera: Encyrtidae) was obtained through next-generation sequencing, making the first reported complete mitochondrial genome of the genus Zaomma. The mitochondrial genome is 15,648 bp in length and includes 37 classical eukaryotic mitochondrial genes along with an A + T rich region. All 13 protein-coding genes (PCGs) initiate with typical ATN codons. Of these, 10 PCG genes terminate with TAA, while three terminate with TAG. Additionally, there are 22 tRNA genes, ranging in size from 62 to 70 bp. The maximum likelihood phylogenetic tree was constructed based on 13 PCGs, indicates that Z. eriococci is closely related to Tassonia gloriae. This mitochondrial genome will serve as a valuable molecular resource for species identification, genetic analysis, and comparative genomic studies of Z. eriococci, contributing to the growing collection of mitochondrial genomes within the family Encyrtidae.

3.
J Mater Chem B ; 12(28): 6774-6804, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38920094

RESUMO

In the last few decades, tear-based biosensors for continuous glucose monitoring (CGM) have provided new avenues for the diagnosis of diabetes. The tear CGMs constructed from nanomaterials have been extensively demonstrated by various research activities in this field and are gradually witnessing their most prosperous period. A timely and comprehensive review of the development of tear CGMs in a compartmentalized manner from a nanomaterials perspective would greatly broaden this area of research. However, to our knowledge, there is a lack of specialized reviews and comprehensive cohesive reports in this area. First, this paper describes the principles and development of electrochemical glucose sensors. Then, a comprehensive summary of various advanced nanomaterials recently reported for potential applications and construction strategies in tear CGMs is presented in a compartmentalized manner, focusing on sensing properties. Finally, the challenges, strategies, and perspectives used to design tear CGM materials are emphasized, providing valuable insights and guidance for the construction of tear CGMs from nanomaterials in the future.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Nanoestruturas , Lágrimas , Dispositivos Eletrônicos Vestíveis , Nanoestruturas/química , Humanos , Lágrimas/química , Glucose/análise
4.
BMC Genomics ; 25(1): 587, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862915

RESUMO

BACKGROUND: The field of bee genomics has considerably advanced in recent years, however, the most diverse group of honey producers on the planet, the stingless bees, are still largely neglected. In fact, only eleven of the ~ 600 described stingless bee species have been sequenced, and only three using a long-read (LR) sequencing technology. Here, we sequenced the nuclear and mitochondrial genomes of the most common, widespread and broadly reared stingless bee in Brazil and other neotropical countries-Tetragonisca angustula (popularly known in Brazil as jataí). RESULTS: A total of 48.01 Gb of DNA data were generated, including 2.31 Gb of Pacific Bioscience HiFi reads and 45.70 Gb of Illumina short reads (SRs). Our preferred assembly comprised 683 contigs encompassing 284.49 Mb, 62.84 Mb of which (22.09%) corresponded to 445,793 repetitive elements. N50, L50 and complete BUSCOs reached 1.02 Mb, 91 contigs and 97.1%, respectively. We predicted that the genome of T. angustula comprises 17,459 protein-coding genes and 4,108 non-coding RNAs. The mitogenome consisted of 17,410 bp, and all 37 genes were found to be on the positive strand, an unusual feature among bees. A phylogenomic analysis of 26 hymenopteran species revealed that six odorant receptor orthogroups of T. angustula were found to be experiencing rapid evolution, four of them undergoing significant contractions. CONCLUSIONS: Here, we provided the first nuclear and mitochondrial genome assemblies for the ecologically and economically important T. angustula, the fourth stingless bee species to be sequenced with LR technology thus far. We demonstrated that even relatively small amounts of LR data in combination with sufficient SR data can yield high-quality genome assemblies for bees.


Assuntos
Genoma Mitocondrial , Filogenia , Animais , Abelhas/genética , Núcleo Celular/genética , Anotação de Sequência Molecular , Polinização , Genômica/métodos , Genoma de Inseto , Análise de Sequência de DNA
5.
Chem Biodivers ; 21(8): e202400596, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38804585

RESUMO

Three polysaccharides, PTC, PTH, and PTB, were extracted from Pinellia ternata using three different extraction conditions: room temperature water, hot water, and 2 % Na2CO3 solution. PTC and PTH were composed of rhamnose, glucose, galactose, mannose, glucuronic acid, galacturonic acid, and arabinose, which combine to form complex structures. PTB was composed solely of glucose and rhamnose. Further analysis indicated that PTC and PTB exhibited triple-helix structures. PTC showed the highest scavenging capacity against DPPH, superoxide anion, and hydroxyl radicals, with half maximal inhibitory concentrations (IC50) of 1004.1, 1584.1, and 1584.1 µg/mL, respectively. Additionally, PTC, PTH, and PTB were subjected to sulfation, phosphorylation, and selenization, resulting in the production of nine derivates. The distinctive absorptive bands of these derivates were determined through infrared spectroscopy. Selenized and sulfated derivates have shown significant antitumor and immunoenhancing properties. Our findings revealed that at 400 µg/mL, the inhibition rate of selenated PTB on HeLa cells was 54.2 % and that on HepG2 cells was 43.1 %. Additionally, selenized PTC displayed significant immunoenhancing activity, with a proliferation rate of 63.7 % at 400 µg/mL in RAW264.7 cells. These results provide valuable evidence supporting the consideration of polysaccharides from Pinellia ternata as a potential candidate for the development of antineoplastic drugs.


Assuntos
Pinellia , Polissacarídeos , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/isolamento & purificação , Humanos , Pinellia/química , Células Hep G2 , Células HeLa , Proliferação de Células/efeitos dos fármacos , Camundongos , Animais , Sobrevivência Celular/efeitos dos fármacos , Picratos/antagonistas & inibidores , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Compostos de Bifenilo/antagonistas & inibidores , Relação Dose-Resposta a Droga , Relação Estrutura-Atividade , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação
6.
J Orthop Surg Res ; 19(1): 238, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38615068

RESUMO

OBJECTIVE: Our study aimed to assess the effectiveness of the simplified S1 vertebral bone quality (VBQ) score in predicting the incidence of proximal junctional kyphosis (PJK) after surgery for degenerative lumbar scoliosis (DLS). METHODS: We reviewed 122 patients with DLS who underwent posterior lumbar decompression and long-segment fusion surgery in our hospital from January 2016 to December 2020. The patients were classified into PJK group and non-PJK group. S1 VBQ scores are determined by signal intensity measurements taken from the mid-sagittal plane of T1-weighted non-contrast MRI. Logistic regression analysis was used to identify factors associated with PJK. Receiver-operating characteristic curve (ROC) analysis was used to evaluate the value of S1 VBQ score in predicting pedicle PJK after DLS. RESULTS: 122 DLS patients (90 females and 32 males) met the inclusion criteria. In addition, 27 patients (22.13%) had PJK at the time of last follow-up. VBQ was higher in PJK patients than non-PJK patients (3.58 ± 0.67 vs. 3.08 ± 0.54, p < 0.001). Preoperatively, patients in the PJK group had a greater TLK than those in the non-PJK group (20.00 ± 6.22 vs. 16.86 ± 5.38, p = 0.011). After surgery, patients in the PJK group had greater TLK (p < 0.001) and PJA (p < 0.001) compared with the non-PJK group. At final FU, patients in the PJK group had greater TK (p = 0.002), TLK (p < 0.001), SVA (p < 0.001), and PJA (p < 0.001) than patients in the non-PJK group (Table 4). In multivariate logistic regression analysis, higher VBQ score (OR 4.565, 95% CI 1.43-14.568, p = 0.010), advanced age (OR 1.119, 95% CI 1.021-1.227, p = 0.016), and larger TLK (OR 1.191, 95% CI 1.041-1.362, p = 0.011) were significant predictors of postoperative PJK in patients with DLS (Table 6). A statistically significant positive correlation existed between VBQ score and PJA change (r = 0.370, p < 0.001). We created ROC curves for VBQ scores as predictors of PJK with a diagnostic accuracy of 72.1% (95% CI 60.15-82.9%.The ideal limit for the VBQ score was 3.205 (sensitivity: 77.8%, specificity: 81.4%). CONCLUSION: To the best of our knowledge, this is the first study to evaluate the effectiveness of the S1 VBQ score in predicting postoperative PJK in DLS. Our study included major risk factors and found that S1 VBQ score was a significant predictor of PJK in patients undergoing DLS surgery. The higher the S1 VBQ score, the higher the probability of PJK.


Assuntos
Cifose , Escoliose , Feminino , Masculino , Humanos , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Coluna Vertebral , Cifose/diagnóstico por imagem , Cifose/etiologia , Cifose/cirurgia , Hospitais , Região Lombossacral
7.
Integr Zool ; 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263700

RESUMO

How many species of life are there on Earth? This is a question that we want to know but cannot yet answer. Some scholars speculate that the number of species may reach 2.2 billion when considering cryptic diversity and that each morphology-based insect species may contain an average of 3.1 cryptic species. With nearly two million described species, such high estimates of cryptic diversity would suggest that cryptic species are widespread. The development of molecular species delimitation has led to the discovery of a large number of cryptic species, and cryptic biodiversity has gradually entered our field of vision and attracted more attention. This paper introduces the concept of cryptic species, how they evolve, and methods by which they may be discovered and confirmed, and provides theoretical and methodological guidance for the study of hidden species. A workflow of how to confirm cryptic species is provided. In addition, the importance and reliability of multi-evidence-based integrated taxonomy are reaffirmed as a way to better standardize decision-making processes. Special focus on cryptic diversity and increased funding for taxonomy is needed to ensure that cryptic species in hyperdiverse groups are discoverable and described. An increased focus on cryptic species in the future will naturally arise as more difficult groups are studied, and thereby, we may finally better understand the rules governing the evolution and maintenance of cryptic biodiversity.

8.
Chem Commun (Camb) ; 60(3): 348-351, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38078506

RESUMO

A facile one-step solvothermal method was developed to synthesize Ir-doped Co-based metal-organic framework (CoIr-MOF) nanoarrays as a bifunctional electrocatalyst for water-glucose co-electrolysis. It was demonstrated that in situ incorporation of a low-content of Ir cations could modulate the electronic structure of Co active centers and thus boost the electrocatalytic performance towards both the hydrogen evolution reaction and glucose-to-formate oxidation reaction.

9.
Clin Neurol Neurosurg ; 236: 108077, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38091705

RESUMO

OBJECTIVE: This study aims to investigate the choice of intervention time and operation mode between nerve and tendon transfer for the treatment of radial nerve palsy (RNP). METHODS: 46 RNP patients underwent nerve transfer (n = 22) and tendon transfer (n = 24). The intraoperative blood loss, main incision length, operation duration, and length of hospital stay and follow-up period of patients in these two groups were recorded and compared. The range of motion (ROM) of the elbow, wrist, fingers, and thumb, the hand grip and pinch strength, the Disabilities of Arm, Shoulder, and Hand (DASH) and the 36-Item Short Form Health Survey (SF-36) scores were measured and compared preoperatively and postoperatively between the two groups. RESULTS: The ROM of thumb and the hand grip strength of patients in the nerve transfer group were greater than that in the tendon transfer (P < 0.05). Both of the two groups indicated significant improvements in the ROM of elbow, wrist, finger, thumb and the hand grip and pinch strength (P < 0.05) postoperatively. The DASH scores decreased significantly at 6 months (P < 0.05) and 12 months (P < 0.05) after surgery in both groups, while the postoperative SF-36 scores significantly increased (P < 0.05). There was no significant difference in postoperative DASH and SF-36 scores between the two groups (P > 0.05). CONCLUSION: In summary, both nerve and tendon transfer techniques are effective treatments for RNP. Nerve transfer is particularly advantageous for early RNP, while tendon transfer is suitable for patients with radial nerve injury more than one year.


Assuntos
Neuropatia Radial , Transferência Tendinosa , Humanos , Transferência Tendinosa/métodos , Neuropatia Radial/cirurgia , Força da Mão , Mãos , Dedos/cirurgia , Nervo Radial/cirurgia , Amplitude de Movimento Articular/fisiologia
10.
Oecologia ; 203(1-2): 205-218, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37831151

RESUMO

There are many factors known to drive species turnover, although the mechanisms by which these operate are less clear. Based on comprehensive datasets from the largest tree diversity experiment worldwide (BEF-China), we used shared herbivore species (zeta diversity) and multi-site generalized dissimilarity modelling to investigate the patterns and determinants of species turnover of Lepidoptera herbivores among study plots across a gradient in tree species richness. We found that zeta diversity declined sharply with an increasing number of study plots, with complete changes in caterpillar species composition observed even at the fine spatial scale of our study. Plant community characteristics rather than abiotic factors were found to play key roles in driving caterpillar compositional turnover, although these effects varied with an increasing number of study plots considered, due to the varying contributions of rare and common species to compositional turnover. Our study reveals details of the impact of phylogeny- and trait-mediated processes of trees on herbivore compositional turnover, which has implications for forest management and conservation and shows potential avenues for maintenance of heterogeneity in herbivore communities.


Assuntos
Herbivoria , Árvores , Biodiversidade , Florestas , Plantas
11.
Environ Res ; 233: 116515, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37380009

RESUMO

Wild bees provide important pollination services, but they face numerous stressors that threaten them and their ecosystem services. Wild bees can be exposed to heavy metal pollution through the consumption of nectar, pollen, and water, which might cause bee decline. While some studies have measured heavy metal concentrations in honeybees, few studies have monitored heavy metal concentrations in wild bees or explored their potential effects on wild bee communities. To investigate the impact of heavy metal pollution on wild bee communities, heavy metal concentrations, including vanadium (V), chromium (Cr), nickel (Ni), cadmium (Cd), Zinc (Zn) and lead (Pb) in multiple wild bee species were measured. Multiple wild bee species, including: Xylocopa tranquabaroroum, Eucera floralia, Apis cerana, and small bee mixtures (representing multiple small wild bee species) were sampled from 18 sites in Quzhou, Zhejiang Province, China. The findings demonstrated that there were significant differences in heavy metal concentrations among different bee species. The concentrations of V, Zn, Cd, and Pb in X. tranquabaroroum, the largest bee species in this study, were lower than that in the other three sample groups. Furthermore, there were significant negative correlations between heavy metal pollution and wild bee diversity and species richness, but not with abundance. Particularly, there was no significant relationship between heavy metal pollution and the abundance of small bees. Given these worrying findings, monitoring multiple heavy metals in wild bees should be conducted for protecting wild bee diversity and securing their pollination services.


Assuntos
Ecossistema , Metais Pesados , Abelhas , Animais , Fazendas , Cádmio/toxicidade , Chumbo/toxicidade , Metais Pesados/toxicidade , Polinização , Zinco
12.
Chem Commun (Camb) ; 59(49): 7623-7626, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37254963

RESUMO

A facile strategy was developed for one-step synthesis of yttrium(Y)-doped cobalt-based metal-organic framework (CoY-MOF) nanosheet arrays. It was demonstrated that in situ doping with a low content of Y can tailor the electronic structure of the MOF structures, thereby improving their electrocatalytic performance for both hydrogen evolution and glycerol oxidation reactions.


Assuntos
Glicerol , Estruturas Metalorgânicas , Cobalto , Hidrogênio , Ítrio
13.
Mol Ecol Resour ; 23(7): 1526-1539, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37202847

RESUMO

The full potential for using DNA barcodes for profiling functional trait diversity has yet to be determined in plants and animals; thus, we outline a general framework for quantifying functional trait diversity of insect community DNA and propose and assess the accuracy of three methods for achieving this. We built a novel dataset of traits and DNA barcodes for wild bees in China. An informatics framework was developed for phylogeny-based integration of these data and prediction of traits for any subject barcodes, which was compared with two distance-based methods. For Phylogenetic Assignment, we additionally conducted a species-level analysis of publically available bee trait data. Under the specimen-level dataset, the rate of trait assignment was negatively correlated with distance between the query and the nearest trait-known reference, for all methods. Phylogenetic Assignment was found to perform best under several criteria; particularly, it had the lowest false-positive rate (rarely returning a state prediction where success was unlikely; where the distance from query to the nearest reference was high). For a wider range of compiled traits, conservative life-history traits showed the highest rates of assignment; for example, sociality was predicted with confidence at 53%, parasitism at 44% and nest location at 33%. As outlined herein, automated trait assignment might be applied at scale to either barcodes or metabarcodes. With further compilation and databasing of DNA barcode and trait data, the rate and accuracy of trait assignment is expected to increase to the point of being a widely viable and informative approach.


Assuntos
Código de Barras de DNA Taxonômico , DNA , Abelhas/genética , Animais , Filogenia , Código de Barras de DNA Taxonômico/métodos , DNA/genética , China
14.
Genome Biol Evol ; 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37170910

RESUMO

Andrena camellia, an effective pollinator of the economicallysignificant crop Camellia oleifera, can withstand the toxic pollen of C. oleifera, making A. camellia a crucial for resource conservation and cultivation of C. oleifera. In this study, the whole genome of A. camellia was sequenced on the Oxford Nanopore platform. The assembled genome size was 340.73 Mb including 50 scaffolds (N50=47.435 Mb) and 131 contigs (N50=17.2 Mb). A total of 11, 258 protein-coding genes were annotated, in addition, 1,104 non-coding RNAs were identified. Further analysis that some chromosomes of A. camellia have a high level of synteny with those of Apis mellifera, Osmia bicornis and Andrena minutula. Thus, our reported genome of A. camellia serves as a valuable resource for studying species evolution, behavioral biology, and adaption to toxic pollen of C. oleifera.

15.
J Orthop Surg Res ; 18(1): 293, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37041547

RESUMO

BACKGROUND: Cervical sagittal parameters are important parameters that reflect the mechanical stress in the sagittal plane of the cervical spine and are an important basis for predicting the clinical status and prognosis of patients. Although it has been confirmed that there is a significant correlation between cervical Modic changes and some sagittal parameters. However, as a newly discovered sagittal parameter, there is no report on the relationship between the K-line tilt and the Modic changes of cervical spine. METHODS: A retrospective analysis was performed for 240 patients who underwent cervical magnetic resonance imaging scan for neck and shoulder pain. Among them, 120 patients with Modic changes, namely the MC(+) group, were evenly divided into three subgroups of 40 patients in each group according to different subtypes, namely MCI subgroup, MCII subgroup and MCIII subgroup. One hundred twenty patients without Modic changes were included in MC(-) group. We measured and compared the sagittal parameters of cervical spine among different groups, including K-line tilt, C2-C7 sagittal axial vertical distance (C2-C7 SVA), T1 slope and C2-7 lordosis. Logistic regression was used to analyse the risk factors of cervical Modic changes. RESULTS: The K-line tilt and C2-7 lordosis were significantly different between MC(+) group and MC(-) group (P < 0.05). The K-line tilt greater than 6.72° is a risk factor for Modic changes in cervical spine (P < 0.05). At the same time, the receiver operating characteristic curve showed that this change had moderate diagnostic value when the area under the curve was 0.77. CONCLUSION: This study shows that the K-line tilt greater than 6.72° is a potential risk factor for Modic changes in cervical spine. When the K-line tilt is greater than 6.72°, we should be alert to the occurrence of Modic changes. TRIAL REGISTRATION NUMBER: 2022ER023-1.


Assuntos
Lordose , Humanos , Lordose/patologia , Estudos Retrospectivos , Vértebras Cervicais/patologia , Pescoço/patologia , Fatores de Risco
16.
Genome Biol Evol ; 15(5)2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37075227

RESUMO

Gaining knowledge on bees is of the utmost importance due to the paramount role that they play in angiosperm pollination. Herein, we provide the first genome assembly of Colletes collaris, a pan-Eurasian cellophane bee. We sequenced 50.53 Gbp of long-read data plus 57.36 Gbp of short-read data in Oxford Nanopore Technologies and Illumina platforms, respectively. The genome assembly consisted of 374.75 Mbp distributed across 374 contigs, with L50 and N50 of 9 and 8.96 Mbp, respectively. We predicted the genome to comprise 20,399 protein-coding genes, 467,947 repeats, and 4,315 non-coding RNA genes. The transcriptome and mitochondrial genome of the species were also assembled. Gene family analysis with 15 insect species identified 14,417 families, 9,517 of them found in C. collaris. A dated phylogenomic analysis revealed high numbers of orthogroups experiencing rapid evolution within Colletes.


Assuntos
Genoma Mitocondrial , Himenópteros , Abelhas/genética , Animais , Himenópteros/genética , Celofane , Genômica , Filogenia
17.
Syst Biol ; 72(4): 781-801, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-36919368

RESUMO

Evolutionary timescales can be inferred by molecular-clock analyses of genetic data and fossil evidence. Bayesian phylogenetic methods such as tip dating provide a powerful framework for inferring evolutionary timescales, but the most widely used priors for tree topologies and node times often assume that present-day taxa have been sampled randomly or exhaustively. In practice, taxon sampling is often carried out so as to include representatives of major lineages, such as orders or families. We examined the impacts of different densities of diversified sampling on Bayesian tip dating on unresolved fossilized birth-death (FBD) trees, in which fossil taxa are topologically constrained but their exact placements are averaged out. We used synthetic data generated by simulations of nucleotide sequence evolution, fossil occurrences, and diversified taxon sampling. Our analyses under the diversified-sampling FBD process show that increasing taxon-sampling density does not necessarily improve divergence-time estimates. However, when informative priors were specified for the root age or when tree topologies were fixed to those used for simulation, the performance of tip dating on unresolved FBD trees maintains its accuracy and precision or improves with taxon-sampling density. By exploring three situations in which models are mismatched, we find that including all relevant fossils, without pruning off those that are incompatible with the diversified-sampling FBD process, can lead to underestimation of divergence times. Our reanalysis of a eutherian mammal data set confirms some of the findings from our simulation study, and reveals the complexity of diversified taxon sampling in phylogenomic data sets. In highlighting the interplay of taxon-sampling density and other factors, the results of our study have practical implications for using Bayesian tip dating to infer evolutionary timescales across the Tree of Life. [Bayesian tip dating; eutherian mammals; fossilized birth-death process; phylogenomics; taxon sampling.].


Assuntos
Fósseis , Mamíferos , Humanos , Animais , Filogenia , Teorema de Bayes , Tempo , Simulação por Computador
18.
Entropy (Basel) ; 25(3)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36981384

RESUMO

Precision electronic warfare is a hot direction for future jamming technology development, and distributed precision jamming (DIPJ) is one of its typical application scenarios. The task objective of DIPJ is to design jamming waveforms so that the jamming energy generated by a set of ultra-sparse array transmitters can be focused in the jamming region of interest while being suppressed in other specific protected regions, which can be viewed as a distributed multiple-input and multiple-output system waveform design problem under a three-dimensional scenario. This paper extends the jamming signal model in DIPJ from narrowband to wideband based on previous work to address a broader range of jamming tasks. After extending the model to wideband signals, a method based on the traditional maximum total energy difference optimization objective is first given for comparison. A wideband jamming waveform design method based on the majorization minimization algorithm with the desired power spectrum matching as the optimization target is designed for the problem that the maximum energy difference method cannot focus energy well in the jamming region. The simulation results show that the presented method can make the jamming energy well concentrated in the target region and evenly distributed over the whole bandwidth, while the energy in the whole bandwidth is suppressed in the protected region.

19.
Proc Biol Sci ; 290(1990): 20221658, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36629113

RESUMO

Human-induced biodiversity loss negatively affects ecosystem function, but the interactive effects of biodiversity change across trophic levels remain insufficiently understood. We sampled arboreal spiders and lepidopteran larvae across seasons in 2 years in a subtropical tree diversity experiment, and then disentangled the links between tree diversity and arthropod predator diversity by deconstructing the pathways among multiple components of diversity (taxonomic, phylogenetic and functional) with structural equation models. We found that herbivores were major mediators of plant species richness effects on abundance, species richness, functional and phylogenetic diversity of predators, while phylogenetic, functional and structural diversity of trees were also important mediators of this process. However, the strength and direction differed between functional, structural and phylogenetic diversity effects, indicating different underlying mechanisms for predator community assembly. Abundance and multiple diversity components of predators were consistently affected by tree functional diversity, indicating that the variation in structure and environment caused by plant functional composition might play key roles in predator community assembly. Our study highlights the importance of an integrated approach based on multiple biodiversity components in understanding the consequences of biodiversity loss in multitrophic communities.


Assuntos
Artrópodes , Aranhas , Animais , Humanos , Ecossistema , Filogenia , Biodiversidade , Plantas
20.
BMC Genomics ; 24(1): 54, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717784

RESUMO

BACKGROUND: Melophagus ovinus is considered to be of great veterinary health significance. However, little is known about the information on genetic mechanisms of the specific biological characteristics and novel methods for controlling M. ovinus. RESULTS: In total, the de novo genome assembly of M. ovinus was 188.421 Mb in size (330 scaffolds, N50 Length: 10.666 Mb), with a mean GC content of 27.74%. A total of 13,372 protein-coding genes were functionally annotated. Phylogenetic analysis indicated that the diversification of M. ovinus and Glossina fuscipes took place 72.76 Mya within the Late Cretaceous. Gene family expansion and contraction analysis revealed that M. ovinus has 65 rapidly-evolving families (26 expansion and 39 contractions) mainly involved DNA metabolic activity, transposases activity, odorant receptor 59a/67d-like, IMD domain-containing protein, and cuticle protein, etc. The universal and tightly conserved list of milk protein orthologues has been assembled from the genome of M. ovinus. Contractions and losses of sensory receptors and vision-associated Rhodopsin genes were significant in M. ovinus, which indicate that the M. ovinus has narrower ecological niches. CONCLUSIONS: We sequenced, assembled, and annotated the whole genome sequence of M. ovinus, and launches into the preliminary genetic mechanisms analysis of the adaptive evolution characteristics of M. ovinus. These resources will provide insights to understand the biological underpinnings of this parasite and the disease control strategies.


Assuntos
Dípteros , Doenças dos Ovinos , Moscas Tsé-Tsé , Animais , Ovinos , Filogenia , Ecossistema , Reprodução/genética
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