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1.
Sci China Life Sci ; 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39190128

RESUMO

Understanding the maintenance and shift in reproductive strategies is a fundamental question in evolutionary research. Although many efforts have been made to compare different reproductive strategies, the association between reproductive strategies and lineage divergence is largely unknown. To explore the impact of different reproductive strategies on lineage divergence, we investigated the evolution of clonality in Saxifraga sect. Irregulares+Heterisia. By integrating several lines of evidence, we found that the loss of clonality in Irregulares+Heterisia was associated with a progressive increase in diversification rate and intraspecific morphological diversity but with a reduction in species distribution range. Our findings provide insights into the ecological and evolutionary effects of different reproductive strategies, suggesting the necessity of integrating clonality into ecological and evolutional research.

2.
Front Plant Sci ; 15: 1387951, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903422

RESUMO

Balancing the biomass requirements of different functions for the purpose of population reproduction and persistence can be challenging for alpine plants due to extreme environmental stresses from both above- and below-ground sources. The presence of ecosystem engineers in alpine ecosystems effectively alleviates microenvironmental stresses, hence promoting the survival and growth of other less stress-tolerant species. However, the influence of ecosystem engineers on plant resource allocation strategies remains highly unexplored. In this study, we compared resource allocation strategies, including biomass accumulation, reproductive effort (RE), root fraction (RF), as well as relationships between different functions, among four alpine plant species belonging to Gentianaceae across bare ground, tussock grass-, cushion-, and shrub-engineered microhabitats. Shrub-engineered microhabitats exerted the strongest effects on regulating plant resource allocation patterns, followed by tussock grass- and cushion-engineered microhabitats. Additionally, apart from microhabitats, population background and plant life history also significantly influenced resource allocation strategies. Generally, plants established within engineered microhabitats exhibited higher biomass accumulation, as well as increased flower, leaf and stem production. Furthermore, individuals within engineered microhabitats commonly displayed lower RF, indicating a greater allocation of resources to above-ground functions while reducing allocation to root development. RE of annual plants was significantly higher than that of perennial plants. However, individuals of annual plants within engineered microhabitats showed lower RE compared to their counterparts in bare ground habitats; whereas perennial species demonstrated similar RE between microhabitat types. Moreover, RE was generally independent of plant size in bare-ground habitats but exhibited size-dependency in certain populations for some species within specific engineered microhabitat types. However, size-dependency did exist for absolute reproductive and root biomass allocation in most of the cases examined here. No trade-offs were observed between flower mass and flower number, nor between leaf mass and leaf number. The capacity of ecosystem engineers to regulate resource allocation strategies in associated plants was confirmed. However, the resource allocation patterns resulted synergistically from the ecosystem engineering effects, population environmental backgrounds, and plant life history strategies. In general, such regulations can improve individual survival and reproductive potential, potentially promoting population persistence in challenging alpine environments.

3.
Int Urol Nephrol ; 55(7): 1677-1684, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37179520

RESUMO

PURPOSE: To assess the safety and effectiveness of the 4.5/6.5 Fr ureteroscopic laser lithotripsy (URSL) under topical intraurethral anesthesia (TIUA) compared to spinal anesthesia (SA). METHODS: A retrospective study was conducted on 47 (TIUA: SA = 23:24) patients receiving 4.5/6.5 Fr URSL from July 2022 to September 2022. For the TIUA group, atropine, pethidine, and phloroglucinol were used apart from lidocaine. In the SA group, patients received lidocaine and bupivacaine. We compare the two groups including stone-free rate (SFR), procedure time, anesthesia time, overall operative time, hospital stay, anesthesia failure, intraoperative pain, need for additional analgesia, cost, and complications. RESULTS: The conversion rate in the TIUA group was 4.35% (1/23). SFR was 100% in both groups. Surgical waiting time and anesthesia time were longer in the SA group (P < 0.001). There were no statistical differences in operational time and intraoperative pain. Patients developed grade 0-1 ureteral injuries. Post-surgical time out of bed was noticeably faster in the TIUA group (P < 0.001). The post-operative complication rate including vomiting and back pain was lower in the TIUA group (P = 0.005). CONCLUSION: TIUA had an equal surgical success rate and controlled patients' intraoperative pain as SA. It was superior in terms of TIUA's patient admission, waiting time for surgery, anesthesia time, post-operative time out of bed, low complications, and costs, especially for females.


Assuntos
Litotripsia a Laser , Litotripsia , Cálculos Ureterais , Feminino , Humanos , Litotripsia a Laser/efeitos adversos , Litotripsia a Laser/métodos , Litotripsia/métodos , Ureteroscopia/efeitos adversos , Ureteroscopia/métodos , Estudos Retrospectivos , Cálculos Ureterais/cirurgia , Resultado do Tratamento , Anestesia Local , Dor
4.
Nanomaterials (Basel) ; 13(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36678087

RESUMO

Aramid nanofibers (ANFs) were successfully produced by deprotonation of Kevlar fiber followed by grafting epichlorohydrin in dimethyl sulfoxide solution. The ANFs were then incorporated into carboxylated acrylonitrile butadiene rubber (XNBR) by means of latex blending, followed by vulcanization. The interaction between ANFs and XNBR, and the effects of ANFs on the mechanical strength, dielectric properties, and thermal stability of ANF/XNBR nanocomposites were investigated. The results revealed that hydrogen bonding and covalent bonding interactions existed between ANFs and the XNBR matrix and played a critical role in the reinforcement of ANFs to XNBR nanocomposites. After adding 5 phr (parts per hundred rubber) of ANFs, the XNBR nanocomposite exhibited a significant improvement in mechanical properties, namely a 182% increase in tensile strength and a 101% increase in tear strength. In addition, the dielectric constant and thermal properties of ANF/XNBR also increased dramatically. ANFs may thus make an ideal candidate for high-performance rubber materials.

5.
PhytoKeys ; 184: 19-26, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34759725

RESUMO

Saxifragaviridiflora, a remarkable new species of the genus Saxifragasect.Irregulares (Saxifragaceae) from Guangxi, is described and illustrated herein. This new species morphologically differs from all known S.sect.Irregulares taxa by its greenish petals, verruculose sepals, and thick leathery leaf blade abaxially scarlet with white spots.

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