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Understanding the drivers of species richness patterns is a major goal of ecology and evolutionary biology, and the drivers vary across regions and taxa. Here, we assessed the influence of environmental factors and evolutionary history on the pattern of species richness in the genus Sorbus (110 species). We mapped the global species richness pattern of Sorbus at a spatial resolution of 200 × 200 km, using 10,652 specimen records. We used stepwise regression to assess the relationship between 23 environmental predictors and species richness and estimated the diversification rate of Sorbus based on chloroplast genome data. The effects of environmental factors were explained by adjusted R2, and evolutionary factors were inferred based on differences in diversification rates. We found that the species richness of Sorbus was highest in the Hengduan Mountains (HDM), which is probably the center of diversity. Among the selected environmental predictors, the integrated model including all environmental predictors had the largest explanatory power for species richness. The determinants of species richness show regional differences. On the global and continental scale, energy and water availability become the main driving factors. In contrast, climate seasonality is the primary factor in the HDM. The diversification rate results showed no significant differences between HDM and non-HDM, suggesting that evolutionary history may have limited impact on the pattern of Sorbus species richness. We conclude that environmental factors play an important role in shaping the global pattern of Sorbus species richness, while diversification rates have a lesser impact. [ABSTRACT FROM AUTHOR]

The thermal-reflective coating technology can effectively realize the active cooling of asphalt pavement, thus delaying the occurrence of pavement rutting. Although solid fillers are usually used to absorb light and weaken light dazzle in traditional thermal-reflective coatings, this method makes the filler component complicated and the coatings more viscous and increases the difficulty of painting the coating material on the pavement surface. On account of all the aforementioned factors, this experimental study aims to effectively improve the performance of the thermal-reflective coating with liquid silicone rubber addition in which epoxy resin is the base material and rutile titanium dioxide is the pigment filler for the coating film. Through lab experiments, the effects of the proper liquid silicone rubber dosage on the glossiness, cooling performance, and hardness of the thermal-reflective coating are studied and analyzed. The experimental results show that the liquid silicone is very effective for coating toughness improvement. The thermal-reflective coating, when the liquid silicone rubber dosage changes from 10 to 14 wt%, exhibits a matt state, and its glossiness can be controlled below 30 GU, which meets the safety and antiglare requirements of traffic vehicles. It demonstrates that liquid silicone rubber can influence the viscosity of the thermal-reflective coatings, and when the liquid silicone dosage reaches 16 wt%, the viscosity of the coating increases by 7.26 wt% less than that of the solid matting filler. Liquid silicone rubber can also influence the cooling effect of the thermal-reflective coatings, with the liquid silicone rubber dosage of 16 wt%, the asphalt pavement temperature can reduce 0.5°C. Besides, liquid silicone rubber reduces the hardness of the coatings, the coating hardness is 6H when the liquid silicone rubber dosage is 0–10 wt%, and the hardness of the coating reduces to 5H when liquid silicone dosage is from 12 to 16 wt%, which meets the actual requirements. Therefore, this article recommends a 12 wt% dosage of the liquid silicone rubber to be used as a matting filler for the thermal-reflective coatings.

Prunus xueluoensis C. H. Nan & X. R. Wang is a new species of the Subg. Cerasus Mill., described by C. H. Nan and X. R. Wang in 2013. Since the publication of P. xueluoensis, its taxonomic status has been the subject of ongoing debate. This study focuses on wild populations of P. xueluoensis and Prunus serrulata (Lindley) London, utilizing 18 pairs of SSR molecular markers and variations in chloroplast DNA sequences (matK, trnD-E, and trnS-G) to delineate the relationship between the two species. The results showed that P. serrulate (N = 12.400, Na = 5.144, H = 0.578, I = 1.129, Ho = 0.493) and P. xueluoensis (N = 13.625, Na = 6.264, H = 0.614, I = 1.342, Ho = 0.495) populations exhibit rich genetic diversity, which may be related to their wide geographical distribution. The CpDNA genetic diversities of P. serrulata (Hd = 0.553, Pi = 0.00136) and P. xueluoensis (Hd = 0.496, Pi = 0.00180) are at a high level within the Subg. Cerasus Mill. The UPGMA clustering, along with MP and ML phylogenetic trees, show that the unique haplotypes of P. xueluoensis cluster separately as a terminal branch in the evolutionary tree with high support. The shared haplotypes and unique haplotypes of P. serrulata are predominantly located at the base of the phylogenetic tree, suggesting that the two species have diverged. In the TCS haplotype network, the central and key node haplotypes are primarily unique to P. serrulata and shared haplotypes, while the unique haplotypes of P. xueluoensis are all distributed along the network's periphery. Both P. serrulata (Nst = 0.254, Gst = 0.103, Nst/Gst = 2.466, p < 0.05) and P. xueluoensis (Nst = 0.366, Gst = 0.268, Nst/Gst = 1.366, p < 0.05) exhibit phylogeographic structures. However, when considered as a whole, the combined entity of P. serrulata and P. xueluoensis does not show a significant phylogeographic structure (Nst = 0.317, Gst = 0.400, Nst/Gst = 0.793, p < 0.05), which supports the classification of these as two distinct species. The estimate of the average age of the latest common ancestor of P. serrulata and P. xueluoensis is 3.22 mya (PP = 1; 95% HPD: 3.07~3.46 mya). Due to environmental differences in altitude, the group of P. serrulata differentiated in the expansion into the cold and humid alpine environment and gradually formed P. xueluoensis. The findings support the classification of P. serrulata and P. xueluoensis as two distinct species. [ABSTRACT FROM AUTHOR]

Prunus discoidea is a unique cherry blossom germplasm resource native to China. It is widely distributed across the provinces of Anhui, Zhejiang, Jiangxi, Jiangsu, and Henan, with significant variation. We employed phylogeographic analysis to reveal the evolutionary history of P. discoidea to better understand its genetic diversity and structure. This study provides more accurate molecular insights for the effective conservation and utilization of this germplasm resource. We conducted a phylogeographic analysis of 348 individual plants from 13 natural populations using three fragments (rpoB, rps16, and trnD–E) of chloroplast DNA (cpDNA) and one fragment (ITS) of ribosomal DNA. The results revealed that P. discoidea demonstrates a significant level of genetic diversity (Hd = 0.782; Rd = 0.478). Gene flow among populations was limited, and the variation within populations was the main source of genetic diversity in P. discoidea (among populations: 34.26%, within populations: 65.74%). Regarding genetic differences among populations, Nst (0.401) showed greater differences than Gst (0.308; p < 0.05), demonstrating that there was a significant geographical structure of lineage. One lineage was the central region of Anhui and the western region of Hubei. The other lineage was the Jiangsu region and the Zhejiang region. P. discoidea diverged from Prunus campanulata approximately 1.5 million years ago, during the Pleistocene epoch. This study provides a scientific theoretical basis for the conservation and utilization of germplasm resources of P. discoidea. [ABSTRACT FROM AUTHOR]

SUMMARY: When interspecific gene flow is common, species relationships are more accurately represented by a phylogenetic network than by a bifurcating tree. This study aimed to uncover the role of introgression in the evolution of Osmanthus, the only genus of the subtribe Oleinae (Oleaceae) with its distribution center in East Asia. We built species trees, detected introgression, and constructed networks using multiple kinds of sequencing data (whole genome resequencing, transcriptome sequencing, and Sanger sequencing of nrDNA) combined with concatenation and coalescence approaches. Then, based on well‐understood species relationships, historical biogeographic analyses and diversification rate estimates were employed to reveal the history of Osmanthus. Osmanthus originated in mid‐Miocene Europe and dispersed to the eastern Tibetan Plateau in the late Miocene. Thereafter, it continued to spread eastwards. Phylogenetic conflict is common within the 'Core Osmanthus' clade and is seen at both early and late stages of diversification, leading to hypotheses of net‐like species relationships. Incomplete lineage sorting proved ineffective in explaining phylogenetic conflicts and thus supported introgression as the main cause of conflicts. This study elucidates the diversification history of a relict genus in the subtropical regions of eastern Asia and reveals that introgression had profound effects on its evolutionary history. [ABSTRACT FROM AUTHOR]

Introduction Cervical cancer is a common malignancy that affects women worldwide and causes high mortality (Peralta-Zaragoza et al. 2012). Although surgery and chemotherapy have improved the clinical outcome for cervical [...], Targeting mitochondria is an attractive strategy for cancer therapy due to the essential roles of mitochondria in cancer cell energy metabolism. In this study, we show that mefloquine, an antibiotic drug, effectively targets cervical cancer cells through impairing mitochondrial function. Mefloquine dose-dependently induces apoptosis and inhibits proliferation and anchorage-independent colony formation of multiple cervical cancer cell lines. Mefloquine alone inhibits cervical tumor growth in vivo and its combination with paclitaxel is synergistic in inhibiting tumor growth. Mechanistically, mefloquine inhibits mitochondrial function via inhibiting mitochondrial respiration, decreasing membrane potential, increasing ROS generation, and decreasing ATP level. We further show that mefloquine suppresses activation of mTOR signaling pathway in HeLa cells. However, the inhibitory effects of mefloquine on survival, colony formation, and ATP are abolished in mitochondrial respiration-deficient HeLa [ρ.sup.0] cells, demonstrating that mefloquine acts on cervical cancer cells via targeting mitochondrial respiration. Inhibition of mTOR signaling pathway by mefloquine was also reversed in HeLa [ρ.sup.0] cells, suggesting deactivation of mTOR pathway as a consequence of mitochondria function disruption. Our work suggests that mefloquine is a potential candidate for cervical cancer treatment. Our work also highlights the therapeutic value of anti-mitochondria and establishes the association of mitochondrial function and the activation of mTOR signaling pathway in cervical cancer cells. Key words: cervical cancer, mefloquine, mitochondrial respiration, mTOR signaling. Cibler la mitochondrie constitue une strategie attrayante dans le traitement du cancer en raison du role essentiel que jouent les mitochondries dans le metabolisme energetique des cellules cancereuses. Dans cette etude, nous montrons que la mefloquine, un antibiotique, cible les cellules du cancer du col de l'uterus en portant atteinte a la fonction mitochondriale. De facon proportionnelle a la dose, la mefloquine provoque l'apoptose et inhibe la proliferation de nombreuses lignees de cellules du cancer du col de l'uterus ainsi que leur formation en colonies independantes de l'ancrage. Seule, la mefloquine entraine une inhibition de la croissance des tumeurs du col de l'uterus in vivo, et son association avec le paclitaxel permet d'obtenir un effet synergique d'inhibition de la croissance tumorale. Quant a son mode d'action, la mefloquine entraine une inhibition de la fonction mitochondriale par l'intermediaire de l'inhibition de la respiration mitochondriale, de la diminution du potentiel transmembranaire, de l'augmentation de la production de derives reactifs de l'oxygene et de la diminution des taux d'ATP. Nous montrons aussi que la mefloquine contre l'activation de la voie de signalisation de mTOR dans les cellules HeLa. Cependant, les effets inhibiteurs de la mefloquine sur la survie, la formation de colonies et l'ATP sont annihiles dans les cellules HeLa [ρ.sup.0] dont la respiration mitochondriale est deficiente, ce qui montre que la mefloquine agit sur les cellules du cancer du col de l'uterus en ciblant la respiration mitochondriale. L'inhibition de la voie de signalisation de mTOR par la mefloquine etait aussi contree dans les cellules HeLa [ρ.sup.0], ce qui laisse entendre que la desactivation de la voie de signalisation de mTOR serait une consequence des perturbations de la fonction mitochondriale. Nos travaux laissent penser que la mefloquine est un candidat potentiel pour le traitement du cancer du col de l'uterus. Nos travaux mettent aussi de l'avant la valeur therapeutique des agents anti-mitochondriaux et revelent l'association entre la fonction mitochondriale et l'activation de la voie de signalisation de mTOR dans les cellules du cancer du col de l'uterus. [Traduit par la Redaction] Mots-cles: cancer du col de l'uterus, mefloquine, respiration mitochondriale, signalisation de mTOR.

In order to study the security and reliability of chain force transmission components of note-temperature steam flooding snubbing workover machine lifting operating system,the analysis is carried out by using the finite element software,the distribution of the chain static strength stress is accurately simulated,the result of chain the maximum equivalent stress is less than the yield limit of the material is obtained,and the contact portion of the pin and sleeve is easy to wear,when worn,the chain pitch increase,the service life will be reduced with the increasing of total length of the chain. On this basis,the computing and simulation analysis of the chain fatigue life are carried out,the results show that the structure of are fully satisfy the work requirements under the load conditions.

In order to study the safety and reliability of the seal ram BOP, this article analyzes the structure and principles of ram BOP, draws the reason of seals failure by analyzing the forces of sealant core; uses accurate simulation on plastic core by ANSYS Software and then draws that morph mainly occurs in front of the plastic core. After the scene several simulation experiments, the damage is consistent with the results of finite element analysis.