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1.
Zhen Ci Yan Jiu ; 49(4): 358-366, 2024 Apr 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38649203

RESUMO

OBJECTIVES: To analyze the effects of electroacupuncture (EA) at "Fenglong" (ST40) and "Zusanli" (ST36) of different intensities and durations on rats with non-alcoholic fatty liver disease (NAFLD) based on the protein kinase R-like endoplasmic reticulum kinase (PERK)-activating transcription factor 4 (ATF4)-C/EBP homologous protein (CHOP) signaling pathway, so as to explore its mechanism underlying improvement of NAFLD. METHODS: SD rats were randomly divided into normal diet group, high-fat model group, sham EA group, strong stimulation EA (SEA) group, and weak stimulation EA (WEA) group, with 15 rats in each group. Each group was further divided into 2, 3, and 4-week subgroups. NAFLD rat model was established by feeding a high-fat diet. After successful modeling, rats in the SEA and WEA groups received EA at bilateral ST40 and ST36 with dense and sparse waves (4 Hz/20 Hz) at current intensities of 4 mA (SEA group) and 2 mA (WEA group), lasting for 20 minutes, once a day, 5 days a week with 2 days of rest. The sham EA group only had the EA apparatus connected without electricity. Different duration subgroups were intervened for 2, 3, and 4 weeks. After the intervention, the contents of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in rats were detected by an automatic biochemical analyzer;liver morphological changes were observed by Oil Red O staining;real-time fluorescence quantitative PCR and Western blot were used to detect the expression of PERK, ATF4, and CHOP mRNAs and proteins in the rat liver tissue. RESULTS: In the high-fat model group, there was a significant accumulation of red lipid droplets in the liver cells, which was reduced significantly in the SEA group at the 4th week. Compared with the normal diet group with the same treatment duration, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs and proteins in the liver tissue were elevated (P<0.01) in the high-fat model group . Compared with the high-fat model group with the same treatment duration, the contents of serum ALT, AST, and the expression of PERK, ATF4, CHOP mRNAs and proteins in the liver tissue were decreased (P<0.01, P<0.05) in the SEA and WEA groups. Compared with the sham EA group with the same treatment duration, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs were decreased (P<0.01, P<0.05) in the SEA and WEA groups, the expression of PERK, ATF4, and CHOP proteins in the liver tissue was decreased (P<0.01) in the SEA group at the 2nd, 3rd, and 4th week, the expression of PERK and CHOP proteins at the 2nd, 3rd, 4th week and ATF4 protein at 2nd week in the liver tissue were decreased (P<0.01, P<0.05) in the WEA group. Compared with the SEA group with the same treatment duration, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs and proteins in the liver tissue were elevated (P<0.05, P<0.01) in the WEA group. Compared with the 2-week time point within the groups, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs and PERK proteins in the liver tissue were decreased (P<0.01, P<0.05) in the SEA and WEA groups at 3rd and 4th week, the expression of ATF4 proteins in the liver tissue was decreased (P<0.01) in the SEA group at 3rd and 4th week, and the expression of CHOP proteins in the liver tissue was decreased (P<0.01) in the SEA group at 4th week and in the WEA group at 3rd and 4th week. Compared with the 3-week time point within the groups, the contents of serum ALT, AST, and the expression of PERK, ATF4, and CHOP mRNAs were significantly decreased (P<0.05, P<0.01) in the SEA and WEA groups at 4th week, the expression of PERK and CHOP proteins in the liver tissue was decreased (P<0.01) in the SEA and WEA groups at 4th week, and the expression of ATF4 protein in the liver tissue was decreased (P<0.05) in the SEA group at 4th week. CONCLUSIONS: EA at ST40 and ST36 can significantly improve liver function in NAFLD rats, and its mechanism of action may involve inhibiting PERK expression thereby targeting the downstream ATF4/CHOP signaling pathway to suppress endoplasmic reticulum stress, exerting a liver protective effect;the optimal effect was observed with EA intensity of 4 mA for 4 weeks.


Assuntos
Fator 4 Ativador da Transcrição , Pontos de Acupuntura , Eletroacupuntura , Fígado , Hepatopatia Gordurosa não Alcoólica , Ratos Sprague-Dawley , Transdução de Sinais , Fator de Transcrição CHOP , eIF-2 Quinase , Animais , Ratos , Fator 4 Ativador da Transcrição/metabolismo , Fator 4 Ativador da Transcrição/genética , eIF-2 Quinase/metabolismo , eIF-2 Quinase/genética , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/terapia , Hepatopatia Gordurosa não Alcoólica/genética , Fator de Transcrição CHOP/metabolismo , Fator de Transcrição CHOP/genética
2.
Sci China Life Sci ; 67(4): 817-828, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38217639

RESUMO

The Convention on Biological Diversity seeks to conserve at least 30% of global land and water areas by 2030, which is a challenge but also an opportunity to better preserve biodiversity, including flowering plants (angiosperms). Herein, we compiled a large database on distributions of over 300,000 angiosperm species and the key functional traits of 67,024 species. Using this database, we constructed biodiversity-environment models to predict global patterns of taxonomic, phylogenetic, and functional diversity in terrestrial angiosperms and provide a comprehensive mapping of the three diversity facets. We further evaluated the current protection status of the biodiversity centers of these diversity facets. Our results showed that geographical patterns of the three facets of plant diversity exhibited substantial spatial mismatches and nonoverlapping conservation priorities. Idiosyncratic centers of functional diversity, particularly of herbaceous species, were primarily distributed in temperate regions and under weaker protection compared with other biodiversity centers of taxonomic and phylogenetic facets. Our global assessment of multifaceted biodiversity patterns and centers highlights the insufficiency and unbalanced conservation among the three diversity facets and the two growth forms (woody vs. herbaceous), thus providing directions for guiding the future conservation of global plant diversity.


Assuntos
Magnoliopsida , Filogenia , Biodiversidade , Plantas , Ecossistema , Conservação dos Recursos Naturais
3.
Ecol Lett ; 27(1): e14364, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38225803

RESUMO

Plant-soil feedback (PSF) is an important mechanism determining plant community dynamics and structure. Understanding the geographic patterns and drivers of PSF is essential for understanding the mechanisms underlying geographic plant diversity patterns. We compiled a large dataset containing 5969 observations of PSF from 202 studies to demonstrate the global patterns and drivers of PSF for woody and non-woody species. Overall, PSF was negative on average and was influenced by plant attributes and environmental settings. Woody species PSFs did not vary with latitude, but non-woody PSFs were more negative at higher latitudes. PSF was consistently more positive with increasing aridity for both woody and non-woody species, likely due to increased mutualistic microbes relative to soil-borne pathogens. These findings were consistent between field and greenhouse experiments, suggesting that PSF variation can be driven by soil legacies from climates. Our findings call for caution to use PSF as an explanation of the latitudinal diversity gradient and highlight that aridity can influence plant community dynamics and structure across broad scales through mediating plant-soil microbe interactions.


Assuntos
Plantas , Solo , Microbiologia do Solo , Simbiose , Retroalimentação
4.
Neural Netw ; 172: 106105, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38232428

RESUMO

In this article, an adaptive optimal consensus control problem is studied for multiagent systems in the strict-feedback structure with intermittent constraints (the constraints appear intermittently). More specifically, by designing a novel switch-like function and an improved coordinate transformation, the constrained states are converted into unconstrained states, and the problem of intermittent constraints is resolved without requiring "feasibility conditions". In addition, using the composite learning algorithm and neural networks to construct the identifier, a simplified identifier-actor-critic-based reinforcement learning strategy is proposed to obtain the approximate optimal controller under the framework of backstepping. Meanwhile, with the aid of the nonlinear dynamic surface control technique, the issue of "explosion of complexity" in backstepping is removed, and the requirements for filter parameters are loosened. Based on Lyapunov stability theory, it is demonstrated that all signals in the closed-loop system are bounded. Finally, two simulation examples are used to verify the effectiveness of the proposed method.


Assuntos
Algoritmos , Redes Neurais de Computação , Consenso , Simulação por Computador , Dinâmica não Linear
5.
Aquac Nutr ; 2023: 4912141, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38077279

RESUMO

The aim of this trial was to investigate the effects of apple polyphenols (AP) and taurine (TA) on the growth performance, tissue morphology, and lipid and glucose metabolism in rice field eel fed diets with high oxidized fish oil (OFO). A 10-week feeding experiment was conducted using juveniles (initial body weight 16.66 ± 0.02 g) fed five different diets. Three diets were formulated with various levels of OFO at 9.5, 600, and 800 meq·kg-1 and named as Control, POV600, and POV800 diet, respectively. The other two diets were POV600 and POV800 supplemented with 0.5% AP and 0.2% TA, respectively. Compared to the Control group, only the eels fed POV800 exhibited an increase in weight gain and specific growth rate along with a reduction in feed conversion ratio. AP and TA did not affect growth performance; juveniles fed AP, however, showed a decrease in liver weight. Both POV600 and POV800 decreased nuclei number and increased vacuoles size in the liver. POV800 damaged the intestinal structure integrity and reduced goblet cells number. AP repaired the liver damage on nuclei number and vacuoles size in fish fed with POV600 diet, while TA mitigated intestinal histopathological damage on intact structure and goblet cells number. The mRNA expression level of liver ampkα in fish fed AP was upregulated, while dietary TA upregulated the mRNA expression levels of liver ampkα and accα. In the muscle, POV600 downregulated mRNA expression levels of accα, cpt1, and lipin, whereas POV800 upregulated mRNA expression levels of accα, pparα, and lipin. Dietary AP and TA could counteract the effects of POV600 and POV800 diet on muscle lipid metabolism. Both POV600 and POV800 diets upregulated mRNA expression levels of liver pck1 and gsk3α. AP and TA both downregulated mRNA expression level of liver pck1, while only TA downregulated the expression of liver gsk3α. AP increased the mRNA expression level of gsk3α in muscle. In summary, inclusion of AP and TA did not affect growth performance but showed a potential to alleviate liver or intestinal damages induced by a high OFO diet. Dietary AP and TA were also found to regulate mRNA expression of genes related to lipid and glucose metabolism.

6.
Proc Biol Sci ; 290(2011): 20231926, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37989241

RESUMO

The evolution of dispersal modes has been proposed to promote the diversification of angiosperms. However, little is known about the relative impact of different dispersal modes on plant diversification. We test the association between dispersal modes and diversification rates using Rhamnaceae, the cosmopolitan buckthorn family, as a model. We found that species with diplochory have the highest diversification rates followed by those with myrmecochory and ballistic dispersal, while lineages dispersed by vertebrates and wind have relatively low diversification rates. The difference in diversification rates may be closely linked to the difference in dispersal distance and ecological interactions implied by each dispersal mode. Species which disperse over larger geographical distances may have much higher speciation rates due to the increased chance of establishing isolated populations due to geological barriers or habitat fragmentation. However, long-distance dispersal may also increase the chance of extinction. By contrast, species with short-distance dispersal modes may have low speciation rates. Complex interactions with the surrounding environment may, however, impact diversification rates positively by increasing plant survival and reproductive success.


Assuntos
Magnoliopsida , Rhamnaceae , Animais , Filogenia , Ecossistema , Geografia , Especiação Genética
7.
Sci Adv ; 9(43): eadg2555, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37878700

RESUMO

Floral symmetry plays an important role in plant-pollinator interactions and may have remarkable impacts on angiosperm diversification. However, spatiotemporal patterns in floral symmetry and drivers of these patterns remain unknown. Here, using newly compiled floral symmetry (actinomorphy versus zygomorphy) data of 279,877 angiosperm species and their distributions and phylogenies, we estimated global geographic patterns and macroevolutionary dynamics of floral symmetry. We found that frequency of actinomorphic species increased with latitude, while that of zygomorphic species decreased. Solar radiation, present-day temperature, and Quaternary temperature change correlated with geographic variation in floral symmetry frequency. Evolutionary transitions from actinomorphy to zygomorphy dominated floral symmetry evolution, although the transition rate decreased with decreasing paleotemperature throughout the Cenozoic. Notably, we found that zygomorphy may not favor diversification of angiosperms as previously observed in some clades. Our study demonstrates the influence of (paleo)climate on spatiotemporal patterns in floral symmetry and challenges previous views about role of flower symmetry in angiosperm diversification.


Assuntos
Magnoliopsida , Magnoliopsida/genética , Filogenia , Flores/genética , Clima , Temperatura , Evolução Biológica
8.
New Phytol ; 240(4): 1647-1658, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37638474

RESUMO

The geographic distribution of plant diversity matches the gradient of habitat heterogeneity from lowlands to mountain regions. However, little is known about how much this relationship is conserved across scales. Using the World Checklist of Vascular Plants and high-resolution biodiversity maps developed by species distribution models, we investigated the associations between species richness and habitat heterogeneity at the scales of Eurasia and the Hengduan Mountains (HDM) in China. Habitat heterogeneity explains seed plant species richness across Eurasia, but the plant species richness of 41/97 HDM families is even higher than expected from fitted statistical relationships. A habitat heterogeneity index combining growing degree days, site water balance, and bedrock type performs better than heterogeneity based on single variables in explaining species richness. In the HDM, the association between heterogeneity and species richness is stronger at larger scales. Our findings suggest that high environmental heterogeneity provides suitable conditions for the diversification of lineages in the HDM. Nevertheless, habitat heterogeneity alone cannot fully explain the distribution of species richness in the HDM, especially in the western HDM, and complementary mechanisms, such as the complex geological history of the region, may have contributed to shaping this exceptional biodiversity hotspot.


Assuntos
Ecossistema , Traqueófitas , Humanos , Biodiversidade , Plantas , Sementes
9.
Artigo em Inglês | MEDLINE | ID: mdl-37603472

RESUMO

In this article, an adaptive optimal consensus control problem is studied for multiagent systems (MASs) with external disturbances, unmeasurable states, and prescribed constraints. First, by using neural networks (NNs), a composite observer is constructed to estimate the unmeasurable states and disturbances simultaneously. Then, the consensus error is guaranteed within a prescribed boundary by presenting an improved prescribed performance control (PPC) technique, and the initial conditions for the error are eliminated. In addition, the updating laws of actor-critic NNs are established by using a simplified reinforcement learning (RL) algorithm based on the uniqueness of optimal solution, and the asymmetric input saturation is resolved by designing auxiliary system instead of using nonquadratic cost functions in other optimal control methods. Finally, the boundedness of all signals in the closed-loop system is proved by using Lyapunov stability theory. The effectiveness of the proposed control method is verified by a simulation example.

10.
Nat Commun ; 14(1): 2990, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37253755

RESUMO

Floristic regions reflect the geographic organization of floras and provide essential tools for biological studies. Previous global floristic regions are generally based on floristic endemism, lacking a phylogenetic consideration that captures floristic evolution. Moreover, the contribution of tectonic dynamics and historical and current climate to the division of floristic regions remains unknown. Here, by integrating global distributions and a phylogeny of 12,664 angiosperm genera, we update global floristic regions and explore their temporal changes. Eight floristic realms and 16 nested sub-realms are identified. The previously-defined Holarctic, Neotropical and Australian realms are recognized, but Paleotropical, Antarctic and Cape realms are not. Most realms have formed since Paleogene. Geographic isolation induced by plate tectonics dominates the formation of floristic realms, while current/historical climate has little contribution. Our study demonstrates the necessity of integrating distributions and phylogenies in regionalizing floristic realms and the interplay of macroevolutionary and paleogeographic processes in shaping regional floras.


Assuntos
Clima , Magnoliopsida , Filogenia , Austrália , Magnoliopsida/genética , Regiões Antárticas
11.
Ecol Lett ; 26(5): 778-788, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36922740

RESUMO

Climate projection requires an accurate understanding for soil organic carbon (SOC) decomposition and its response to warming. An emergent view considers that environmental constraints rather than chemical structure alone control SOC turnover and its temperature sensitivity (i.e., Q10 ), but direct long-term evidence is lacking. Here, using compound-specific radiocarbon analysis of soil profiles along a 3300-km grassland transect, we provide direct evidence for the rapid turnover of lignin-derived phenols compared with slower-cycling molecular components of SOC (i.e., long-chain lipids and black carbon). Furthermore, in contrast to the slow-cycling components whose turnover is strongly modulated by mineral association and exhibits low Q10 , lignin turnover is mainly regulated by temperature and has a high Q10 . Such contrasts resemble those between fast-cycling (i.e., light) and mineral-associated slow-cycling fractions from globally distributed soils. Collectively, our results suggest that warming may greatly accelerate the decomposition of lignin, especially in soils with relatively weak mineral associations.


Assuntos
Carbono , Solo , Solo/química , Temperatura , Lignina , Minerais , Microbiologia do Solo
12.
IEEE Trans Neural Netw Learn Syst ; 34(5): 2633-2646, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-34520365

RESUMO

Scene parsing, or semantic segmentation, aims at labeling all pixels in an image with the predefined categories of things and stuff. Learning a robust representation for each pixel is crucial for this task. Existing state-of-the-art (SOTA) algorithms employ deep neural networks to learn (discover) the representations needed for parsing from raw data. Nevertheless, these networks discover desired features or representations only from the given image (content), ignoring more generic knowledge contained in the dataset. To overcome this deficiency, we make the first attempt to explore the meaningful supportive knowledge, including general visual concepts (i.e., the generic representations for objects and stuff) and their relations from the whole dataset to enhance the underlying representations of a specific scene for better scene parsing. Specifically, we propose a novel supportive knowledge mining module (SKMM) and a knowledge augmentation operator (KAO), which can be easily plugged into modern scene parsing networks. By taking image-specific content and dataset-level supportive knowledge into full consideration, the resulting model, called knowledge augmented neural network (KANN), can better understand the given scene and provide greater representational power. Experiments are conducted on three challenging scene parsing and semantic segmentation datasets: Cityscapes, Pascal-Context, and ADE20K. The results show that our KANN is effective and achieves better results than all existing SOTA methods.

13.
Aquac Nutr ; 2023: 3321734, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38174087

RESUMO

The purpose of this trial was to study the positive effects of bile acids (BAs) on growth performance and intestinal health of rice field eel fed with high-lipid diets (HLDs). Rice field eels (initial weight 17.00 ± 0.10 g) were divided into four groups, each group containing four repetitions and feeding with different isonitrogenous diet: control diet containing 7% lipid content, HLDs containing the lipid content increased to 13%, HLDs supplementing with 0.025% BAs and 0.05% BAs, respectively. After 8 weeks, compared control group, the fish fed HLDs had no significant effect on weight gain rate and specific growth rate (P > 0.05), but increased the lipid deposition in tissues and intestinal lipase activity, and damaged to intestinal oxidative stress, inflammatory response, physical barrier, and structural integrity (P < 0.05). Dietary BAs significantly increased weight gain rate and specific growth rate in fish fed with HL diets (P < 0.05) and reduced feed conversation rate (P < 0.05). Further, the eels fed with BAs reduced the total lipid content in liver, muscle, and whole body (P < 0.05). Dietary BAs decreased the activity of intestinal lipase (P < 0.05). Meanwhile, BAs supplemented in HLDs improved intestinal antioxidant capacity through increasing the activities of T-SOD (total superoxide dismutase), GSH-PX (glutathione peroxidase), CAT (catalase), T-AOC (total antioxidant capacity), whereas reducing MDA (malondialdehyde) content (P < 0.05). Moreover, dietary BAs regulated the mRNA expression related to inflammatory response, oxidative stress, and physical barrier in intestine, such as tnf-α, il-8, tlr-8, il-10, nrf2, keap1, claudin12, and claudin15 (P < 0.05). Dietary BAs supplementation also enhanced the intestinal structural integrity characterized by increased fold height and lamina propria width (P < 0.05). This study showed that dietary BAs supplemented in HLDs (13% lipid) could increase the growth performance of rice field eel, reduce lipid deposition in tissues and whole body, and enhance intestinal health.

14.
Biomed Environ Sci ; 35(9): 773-781, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36189992

RESUMO

Objective: Improvement in the quality of life is reflected in the narrowing of the gap between health-adjusted life expectancy (HALE) and life expectancy (LE). The effect of megacity expansion on narrowing the gap is rarely reported. This study aimed to disclose this potential relationship. Methods: Annual life tables were constructed from identified death records and population counts from multiple administrative sources in Guangzhou, China, from 2010 to 2020. Joinpoint regression was used to evaluate the temporal trend. Generalized principal component analysis and multilevel models were applied to examine the county-level association between the gap and social determinants. Results: Although LE and HALE in megacities are increasing steadily, their gap is widening. Socio-economic and health services are guaranteed to narrow this gap. Increasing personal wealth, a growing number of newborns and healthy immigrants, high urbanization, and healthy aging have helped in narrowing this gap. Conclusion: In megacities, parallel LE and HALE growth should be highly considered to narrow their gap. Multiple social determinants need to be integrated as a whole to formulate public health plans.


Assuntos
Qualidade de Vida , Determinantes Sociais da Saúde , Cidades , Nível de Saúde , Humanos , Recém-Nascido , Expectativa de Vida
15.
Microorganisms ; 9(9)2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34576824

RESUMO

Changes in species composition across communities, i.e., ß-diversity, is a central focus of ecology. Compared to macroorganisms, the ß-diversity of soil microbes and its drivers are less studied. Whether the determinants of soil microbial ß-diversity are consistent between soil depths and between abundant and rare microorganisms remains controversial. Here, using the 16S-rRNA of soil bacteria and archaea sampled at different soil depths (0-10 and 30-50 cm) from 32 sites along an aridity gradient of 1500 km in the temperate grasslands in northern China, we compared the effects of deterministic and stochastic processes on the taxonomic and phylogenetic ß-diversity of soil microbes. Using variation partitioning and null models, we found that the taxonomic ß-diversity of the overall bacterial communities was more strongly determined by deterministic processes in both soil layers (the explanatory power of environmental distance in topsoil: 25.4%; subsoil: 47.4%), while their phylogenetic counterpart was more strongly determined by stochastic processes (the explanatory power of spatial distance in topsoil: 42.1; subsoil 24.7%). However, in terms of abundance, both the taxonomic and phylogenetic ß-diversity of the abundant bacteria in both soil layers was more strongly determined by deterministic processes, while those of rare bacteria were more strongly determined by stochastic processes. In comparison with bacteria, both the taxonomic and phylogenetic ß-diversity of the overall abundant and rare archaea were strongly determined by deterministic processes. Among the variables representing deterministic processes, contemporary and historical climate and aboveground vegetation dominated the microbial ß-diversity of the overall and abundant microbes of both domains in topsoils, but soil geochemistry dominated in subsoils. This study presents a comprehensive understanding on the ß-diversity of soil microbial communities in the temperate grasslands in northern China. Our findings highlight the importance of soil depth, phylogenetic turnover, and species abundance in the assembly processes of soil microbial communities.

16.
Ecol Lett ; 24(9): 1835-1847, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34121305

RESUMO

Angiosperm sexual systems are fundamental to the evolution and distribution of plant diversity, yet spatiotemporal patterns in angiosperm sexual systems and their drivers remain poorly known. Using data on sexual systems and distributions of 68453 angiosperm species, we present the first global maps of sexual system frequencies and evaluate sexual system evolution during the Cenozoic. Frequencies of dioecy and monoecy increase with latitude, while hermaphrodites are more frequent in warm and arid regions. Transitions to dioecy from other states were higher than to hermaphroditism, but transitions away from dioecy increased since the Cenozoic, suggesting that dioecy is not an evolutionary end point. Transitions between hermaphroditism and dioecy increased, while transitions to monoecy decreased with paleo-temperature when paleo-temperature >0℃. Our study demonstrates the biogeography of angiosperm sexual systems from a macroecological perspective, and enhances our understanding of plant diversity patterns and their response to climate change.


Assuntos
Magnoliopsida , Evolução Biológica , Plantas , Reprodução
17.
Shanghai Kou Qiang Yi Xue ; 30(2): 191-195, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-34109361

RESUMO

PURPOSE: To investigate the clinical performance of chairside monolithic lithium disilicate glass-ceramics computer-aided design(CAD)-computer aided manufacturing(CAM) crowns, and to analyze the influencing factors of cumulative survival rate. METHODS: Two hundred and fourteen patients who had chairside posterior lithium disilicate glass-ceramic CAD-CAM crowns in Peking University Shenzhen Hospital from March 2015 to March 2017 were enrolled. The crown preparations were milled using Cerec Omnicam system. The clinical and esthetic effects of the crowns were analyzed at 3, 6, 12, 24, and 36 months. The cumulative survival rate of crowns was calculated, and the effects of gender, age, pulp condition, tooth position and adhesive type on the cumulative survival rate were analyzed. SPSS 20.0 software package was used for statistical analysis. RESULTS: After a 36-month follow-up, the failed crowns were mainly caused by marginal integrity, crown fracture and loss of retention. During the observation period of 3, 6, 12, 24 and 36 months, the scores of color, shape, quality of proximal contact, and chewing ability were greater than 9. The cumulative survival rates were 100.00%, 96.17%, 94.89%, 92.77% and 91.06% at 3, 6, 12, 24 and 36 months, respectively. The cumulative survival rate had no significant difference among different gender, age, and dental pulp status(P>0.05). CONCLUSIONS: Chairside monolithic lithium disilicate glass-ceramic CAD-CAM crowns have a high 3-year cumulative survival rate and good esthetic outcome, which is not affected by gender, age, and pulp status with high clinical value.


Assuntos
Planejamento de Prótese Dentária , Estética Dentária , Cerâmica , Desenho Assistido por Computador , Coroas , Porcelana Dentária , Humanos , Teste de Materiais
18.
Front Plant Sci ; 12: 604272, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33796123

RESUMO

Fruit type is a key reproductive trait associated with plant evolution and adaptation. However, large-scale geographical patterns in fruit type composition and the mechanisms driving these patterns remain to be established. Contemporary environment, plant functional traits and evolutionary age may all influence fruit type composition, while their relative importance remains unclear. Here, using data on fruit types, plant height and distributions of 28,222 (∼ 90.1%) angiosperm species in China, we analyzed the geographical patterns in the proportion of fleshy-fruited species for all angiosperms, trees, shrubs, and herbaceous species separately, and compared the relative effects of contemporary climate, ecosystem primary productivity, plant height, and evolutionary age on these patterns. We found that the proportion of fleshy-fruited species per grid cell for all species and different growth forms all showed significant latitudinal patterns, being the highest in southeastern China. Mean plant height per grid cell and actual evapotranspiration (AET) representing ecosystem primary productivity were the strongest drivers of geographical variations in the proportion of fleshy-fruited species, but their relative importance varied between growth forms. From herbaceous species to shrubs and trees, the relative effects of mean plant height decreased. Mean genus age had significant yet consistently weaker effects on proportion of fleshy-fruited species than mean plant height and AET, and environmental temperature and precipitation contributed to those of only trees and shrubs. These results suggest that biotic and environmental factors and evolutionary age of floras jointly shape the pattern in proportion of fleshy-fruited species, and improve our understanding of the mechanisms underlying geographical variations in fruit type composition. Our study also demonstrates the need of integrating multiple biotic and abiotic factors to fully understand the drivers of large-scale patterns of plant reproductive traits.

19.
Sci Total Environ ; 783: 146896, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-33866165

RESUMO

Elevational range shifts of mountain species in response to climate change have profound impact on mountain biodiversity. However, current evidence indicates great controversies in the direction and magnitude of elevational range shifts across species and regions. Here, using historical and recent occurrence records of 83 plant species in a subtropical mountain, Mt. Gongga (Sichuan, China), we evaluated changes in species elevation centroids and limits (upper and lower) along elevational gradients, and explored the determinants of elevational changes. We found that 63.9% of the species shifted their elevation centroids upward, while 22.9% shifted downward. The changes in centroid elevations and range size were more strongly correlated with changes in lower than upper limits of species elevational ranges. The magnitude of centroid elevation shifts was larger than predicted by climate warming and precipitation changes. Our results show complex changes in species elevational distributions and range sizes in Mt. Gongga, and that climate change, species traits and climate adaptation of species all influenced their elevational movement. As Mt. Gongga is one of the global biodiversity hotspots, and contains many threatened plant species, these findings provide support to future conservation planning.


Assuntos
Altitude , Mudança Climática , Biodiversidade , China , Ecossistema , Plantas
20.
Cancer Med ; 10(8): 2865-2876, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33724715

RESUMO

BACKGROUND: Cancer is an important focus of public health worldwide. This study aims to provide a comprehensive overview of temporal trends in incidence and mortality of leading cancer in Guangzhou, China from 2004 to 2015. METHODS: Data were collected from the population-based registry in Guangzhou. Age-standardized incidence rate (ASIR) and age-standardized mortality rate (ASMR) were calculated and Joinpoint regression was used for evaluating the average annual percent changes (AAPC) among the entire study period and the estimated annual percent changes (EAPC) in time segments. The effects of age, period, and birth cohort were assessed by the age-period-cohort model. RESULTS: The age-standardized incidence and mortality by the world standard population decreased significantly among males with AAPC of -1.7% (95% CI: -3.0%, 0.2%) and -2.7% (95% CI: -4.3%, -1.1%) for all malignancies during 2004-2015, while among females, the age-standardized incidence had a non-significant reduction with AAPC of -1.3% (95% CI: -2.8%, 0.2%) and the age-standardized mortality demonstrated a remarkable decline (AAPC -2.0%, 95% CI: -3.6%, -0.3%). For males, the most commonly diagnosed cancers were trachea, bronchus, and lung (TBL), liver, colorectal, nasopharyngeal, stomach, and prostate cancer. For females, breast, TBL, colorectal, liver stomach, and thyroid cancer ranked the top. Unfavorable trends were observed in ASIR of colorectal, thyroid, and prostate cancer. APC models yielded different ages, periods, and birth cohort effect patterns by cancer sites. CONCLUSIONS: Cancer burden remained a public health challenge in Guangzhou as the aging population and lifestyles changes, despite declines in incidence and mortality rates in some cancers. Surveillance of cancer trends contributed to valuable insights into cancer prevention and control.


Assuntos
Neoplasias/epidemiologia , Fatores Etários , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Mortalidade/tendências , Neoplasias/mortalidade , Análise de Regressão
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