Structure Patterns Research Articles

Luminescence properties of complex fluoride Na3CaMg3AlF14 phosphors doped with cerium and europium ions

Ceramic samples of two multi-cation fluoride compositions, namely Na3CaMg3AlF14 doped with Ce3+ or Eu2+ and KCaAl2F9 doped with Eu2+, have been synthesized using a conventional solid-state reaction method. The XRD analysis shows that the new polymorphic modification of Na3CaMg3AlF14 with the cubic A2B2X7 pyrochlore crystal structure (space group Fd3‾m, lattice parameter 10.172 Å) has been obtained. This conclusion is confirmed with the simulation of the XRD pattern for the cubic pyrochlore structure by introducing random occupation of Na+ and Ca2+ ions at the A-type sites as well as Mg2+ and Al3+ ions at the B-type sites in the structure of rhombohedral Na3CaMg3AlF14. It has been shown that doping of the Na3CaMg3AlF14 pyrochlore matrix with Ce3+ ions creates several Ce3+ optical centers with different spectral and decay properties of 5d-4f luminescence. In contrast to that, doping with Eu2+ ions creates a single optical center by the substitution for the Na/Ca A-type site in the cubic Na3CaMg3AlF14 pyrochlore structure. In Eu2+-doped Na3CaMg3AlF14, the Eu2+ emission band caused by the interconfigurational 4f65d – 4f7 transition has a rather narrow width (FWHM = 29 nm) which is considerably less than that observed in Eu2+-doped KCaAl2F9 (FWHM = 44 nm) in which the emission band is broadened due to the existence of two types of sites for doping Eu2+ ions. The Eu2+ ions doped into Na3CaMg3AlF14 and KCaAl2F9 hosts emit not only broad-band 4f65d – 4f7 luminescence but also a narrow-line 4f7 – 4f7 (6P7/2 - 8S7/2) emission which is not observed under excitation to the lowest-energy 4f65d state. It has been shown that both Na3CaMg3AlF14:Eu2+ and KCaAl2F9:Eu2+ demonstrate a rather good thermal stability of luminescence with thermal quenching temperature T1/2 equal to 504 and 573 K, respectively.

Spatial Distribution Pattern of the Mesozooplankton Community in Ross Sea Region Marine Protected Area (RSR MPA) during Summer

The Ross Sea region Marine Protected Area (RSR MPA) is one of the most productive regions in the Southern Ocean. Mesozooplankton intermediates the primary product to the higher predators, such as penguins and seals, in this ecosystem. In this study, the mesozooplankton community structure and spatial pattern in the RSR MPA in January were investigated by using 505 μm-mesh-size bongo net samples. As a result, 37 mesozooplankton taxa with a total mean abundance of 35.26 ind./m3, ranging from 2.94 to 139.17 ind./m3, were confirmed. Of the 37 taxa, 7 occupied almost 84% of the total abundance, with copepods being the main dominant taxa. As shown by our hierarchical analysis, the mesozooplankton community was divided into four groups, each associated with a specific geographical distribution. Group A was composed of stations around Terra Nova Bay and showed relatively low abundance. Group B included stations around the continental slope region. Group D was composed of the Ross Sea continental shelf stations, while group C consisted of stations geographically located between those of groups B and D. These four groups were influenced by various environmental factors, such as water temperature, salinity, and nutrients. In summary, the mesozooplankton community can be separated according to geographical pattern. This pattern is related to several environmental factors.

Breads formulated with avocado pulp powder as a fat substitute: Quality parameters and in vitro inhibition activities.

The aim of the current study was to evaluate the influence of increasing contents (5%-25%) of avocado pulp powder (APP) produced by foam-mat drying (FMD) as a substitute for hydrogenated vegetable fat in bread on its nutritional composition, physical properties, α-amylase, α-glucosidase, and lipase inhibition, total phenolic content, antioxidant activity, color, structure, and x-ray diffraction patterns. The increase in the APP content decreased the values of lipids, carbohydrates, energy, firmness, and specific volume of breads. The inhibition of lipase activity showed a pronounced increase, while the total phenolic content and antioxidant activity were significantly elevated. The color parameters a* and b* were higher in the breads with added APP. The crystalline structure transitioned from type A to type V with 15% APP incorporation. Taken together, these results suggest that APP has potential to act as a healthier substitute for saturated fats in breads, paving the way to develop creative and innovative solutions for the functionalization of bakery food products.

Linking ecosystem multifunctionality to microbial community features in rivers along a latitudinal gradient.

Microorganisms regulate numerous ecosystem functions and show considerable differences along a latitudinal gradient. Although studies have revealed the latitudinal patterns of microbial community structure and single ecosystem function, the latitudinal patterns of ecosystem multifunctionality (EMF) and how microbial communities affect EMF along a latitudinal gradient remain unclear. Here, we collected channel sediments, riparian rhizosphere soils, and riparian bulk soils from 30 rivers across China and calculated EMF using 18 variables related to nitrogen cycling, nutrient pool, plant productivity, and water quality. We also determined microbial diversity (taxonomic and functional) and microbial network complexity using metagenomic sequencing. The results showed that EMF significantly decreased with increasing latitude in riparian rhizosphere and bulk soils but not in channel sediments. Microbial taxonomic and functional richness (observed species) in channel sediments were significantly higher in the low-latitude group than in the high-latitude group. However, microbial co-occurrence networks were more complex in the high-latitude group compared with the low-latitude group. Abiotic factors, primarily geographic and climatic factors, contributed more to EMF than microbial diversity and network complexity parameters in which only betweenness centralization had a significant relationship with EMF. Together, this study provides insight into the latitudinal pattern of EMF in rivers and highlights the importance of large-scale factors in explaining such latitudinal patterns.IMPORTANCEEcosystem multifunctionality (EMF) is the capacity of an ecosystem to provide multiple functions simultaneously. Microorganisms, as dominant drivers of belowground processes, have a profound effect on ecosystem functions. Although studies have revealed the latitudinal patterns of microbial community structure and single ecosystem function, the latitudinal patterns of EMF and how microbial communities affect EMF along a latitudinal gradient remain unclear. We collected channel sediments, riparian rhizosphere soils, and riparian bulk soils from 30 rivers along a latitudinal gradient across China and calculated EMF using 18 variables related to nitrogen cycling, nutrient pool, plant productivity, and water quality. This study fills a critical knowledge gap regarding the latitudinal patterns and drivers of EMF in river ecosystems and gives new insights into how microbial diversity and network complexity affect EMF from a metagenomic perspective.

Considerable genetic diversity and structure despite narrow endemism and limited ecological specialization in the Hayden's ringlet, Coenonympha haydenii.

Understanding the processes that underlie the development of population genetic structure is central to the study of evolution. Patterns of genetic structure, in turn, can reveal signatures of isolation by distance (IBD), barriers to gene flow, or even the genesis of speciation. However, it is unclear how severe range restriction might impact the processes that dominate the development of genetic structure. In narrow endemic species, is population structure likely to be adaptive in nature, or rather the result of genetic drift? In this study, we investigated patterns of genetic diversity and structure in the narrow endemic Hayden's ringlet butterfly. Specifically, we asked to what degree genetic structure in the Hayden's ringlet can be explained by IBD, isolation by resistance (IBR) (in the form of geographic or ecological barriers to migration between populations), and isolation by environment (in the form of differences in host plant availability and preference). We employed a genotyping-by-sequencing (GBS) approach coupled with host preference assays, Bayesian modelling, and population genomic analyses to answer these questions. Our results suggest that despite their restricted range, levels of genetic diversity in the Hayden's ringlet are comparable to those seen in more widespread butterfly species. Hayden's ringlets showed a strong preference for feeding on grasses relative to sedges, but neither larval preference nor potential host availability at sampling sites correlated with genetic structure. We conclude that geography, in the form of IBR and simple IBD, was the major driver of contemporary patterns of differentiation in this narrow endemic species.

Genome-Wide Identification and Expression Analysis of the DA1 Gene Family in Sweet Potato and Its Two Diploid Relatives.

The DA1-like gene family plays a crucial role in regulating seed and organ size in plants. The DA1 gene family has been identified in several species but has not yet been reported in sweet potatoes. In this study, nine, eleven, and seven DA1s were identified in cultivated sweet potato (Ipomoea batatas, 2n = 6x = 90) and its two diploid wild relatives, I. trifida (2n = 2x = 30) and I. triloba (2n = 2x = 30), respectively. The DA1 genes were classified into three subgroups based on their phylogenetic relationships with Arabidopsis thaliana and Oryza sativa (rice). Their protein physiological properties, chromosomal localization, phylogenetic relationships, gene structure, promoter cis-elements, and expression patterns were systematically analyzed. The qRT-PCR results showed that the expression levels of four genes, IbDA1-1, IbDA1-3, IbDA1-6, and IbDA1-7, were higher in the sweet potato leaves than in the roots, fiber roots, and stems. In our study, we provide a comprehensive comparison and further the knowledge of DA1-like genes in sweet potatoes, and provide a theoretical basis for functional studies.

Long‐term differences in population structure, body size and distribution patterns of amphipods and isopods in wetlands with declining hydroperiods

Abstract In many regions, climatic drying is shortening hydroperiods and freshwater biodiversity is declining. Aquatic species that lack a desiccation‐resistant life stage are predicted to have the least ability to persist in drying climates, yet such species may occur in intermittent waterbodies. We examined the distribution of two crustacean species that lack desiccation‐resistant life stages: the isopod Paramphisopus palustris and amphipod Chiltoniidae sp.nov., before and after the commencement of severe climatic drying in Swan Coastal Plain wetlands, south‐western Australia. Historical distribution data for these species were obtained from studies of the same set of wetlands in 1989–1990. We determined whether population or body size differed between hydrological regimes (perennial, semi‐perennial, seasonal) between 1989–1990 and 2018–2019 for both species. Amphipods, isopods and environmental variables were sampled from 42 wetlands in 2018–2019. Thirty‐three wetlands (22 perennial, 11 seasonal) persisted with the same hydrological regime in both time periods and eight wetlands that were perennial in 1989–1990 had shifted to a drier hydrological regime (four became semi‐perennial, four became seasonal) by 2018–2019. Drying wetland hydrological regimes did not correspond to more limited spatial distributions for either species. Hydrological regime had no effect on amphipod counts, although abundances were lower in 2018–2019 than 1989–1990. In 2018–2019, male amphipods were larger than females in seasonal wetlands, but sexes were the same size in perennial wetlands and females were larger than males in semi‐perennial wetlands. Furthermore, amphipods of both sexes were considerably smaller in semi‐perennial than seasonal or perennial wetlands. Isopod distributions differed between the two sampling periods, with populations primarily lost from wetlands that remained perennial. This unexpected result was likely caused by prolonged periods of high summer–autumn water temperatures and stratification in shallow perennial wetlands that caused anoxia in bottom waters and made surface waters excessively hot for isopods. By contrast, drying seasonal wetlands seemingly offered suitable habitat in summer–autumn. Mean isopod head and body length did not differ between hydrological regimes or sexes, but became smaller between 1989–1990 and 2018–2019 (15 mm average body length in 1989 vs. 8.3 mm in 2018–2019; 17 mm maximum size in 1989–1990 vs. 13.2 mm in 2018–2019). The absence of population losses associated with drying hydrological regimes indicates that the current level of drying is within the tolerance range of both species. However, increased temperatures may be causing body size (and possibly fecundity) to decline for isopods. As global warming continues to shorten wetland hydroperiods in many regions, numerous species will struggle to complete their life cycles, leading to extirpation. Our findings suggest that climate change may also cause conditions in perennial wetlands to exceed the tolerances of species that lack desiccation resistance traits. This emphasises the need to better understand both environmental and habitat changes along the drying trajectory in wetlands and the fundamental life‐history and physiological traits that enable the survival of aquatic invertebrates that lack desiccation resistance. This includes not only species responses to drying, but also responses to other stressors (e.g., prolonged stratification) caused by global warming.

Crustal deformation in the vicinity of the Tan-Lu Fault Zone in East China constrained by receiver function analyses

To investigate the spatial distribution of crustal deformation and related geodynamic processes associated with the Tan-Lu Fault Zone (TLFZ) in East China, we measured crustal anisotropy based on the sinusoidal moveout of the P-to-S conversions from the Moho observed on receiver functions. Totally 142 well-defined crustal anisotropy measurements were obtained from the China National Seismic Network and other broadband dense seismic stations, including three stations exhibiting the pattern of a double layered anisotropy structure. The fast orientations observed at stations in the vicinity of the TLFZ were dominantly fault-parallel except for the southernmost part of the study area, where the fast orientations were approximately normal to the strike of the fault zone and may primarily be attributed to the NW-SE oriented Dabie Orogenic Belt. In the North China Block, NW-SE fast orientations were found to be consistent with the dominant orientation of the secondary faults. The Lower Yangtze Block showed two dominant fast orientations. The fault-parallel measurements in the west of the Jiangshao Fault Zone were controlled by the NE-trending faults in the Lower Yangtze Block, while the fast orientations in the east and south of the Jiangshao Fault Zone were dominantly E-W, which could be mainly influenced by the regional principal compressive stress. The average delay time of the entire study area was 0.27 ± 0.07 s. In the vicinity of the TLFZ where fault-parallel fast orientations were observed, an approximately 44% increase in delay time was observed, suggesting a well-developed fault zone.

Elevation gradients alter vegetation attributes in mountain ecosystems of eastern Himalaya, India

The present study describes how vegetation (the tree layer) is shaped along the elevation gradients in the eastern part of the Indian Himalayan Region. Various vegetation attributes, distribution, population structure, and regeneration patterns of 75 tree species belonging to 31 families were studied. Tree species richness shows a low plateau (peaked between 1,300–1,500 m) with a linearly decreasing pattern above 1,500 m asl. Ericaceae was found as the dominant family, followed by Lauraceae and Rosaceae. The distributional pattern of species-to-genera ratio (S/G) did not follow any particular trends, while β-diversity increased along the elevation gradient. The Margalef index of species richness, the Menheink index of species richness, and the Fisher alpha were found to be highest at lower altitudes (1,000–1,500 m), while the Simpson index was highest at middle altitudes (2,600–3,000 m). Random distribution was shown by maximum tree species (47.3%), followed by a contagious distribution (42.9%), and regular distribution (10.8%). The regeneration of tree species was found to be good with a healthier number of seedlings (10.2%), fair (43.5%), poor (30.3%), while 16% were observed not regenerating. Acer laevigatum (1,500 m), Prunus nepalensis (3,300 m), Viburnum sympodiale (3,400 m) were among the new regenerating species at the respective altitudes. The population structure of tree species in terms of proportion of individuals in seedlings, saplings, and the adult class varied in all the elevation transects. Species with better regeneration on upper distribution limits have been recognized as probable for upward movement.

Microgeographic population structuring in a genus of California trapdoor spiders and discovery of an enigmatic new species (Euctenizidae: Promyrmekiaphila korematsui sp. nov.).

The recognition and delineation of cryptic species remains a perplexing problem in systematics, evolution, and species delimitation. Once recognized as such, cryptic species complexes provide fertile ground for studying genetic divergence within the context of phenotypic and ecological divergence (or lack thereof). Herein we document the discovery of a new cryptic species of trapdoor spider, Promyrmekiaphila korematsui sp. nov. Using subgenomic data obtained via target enrichment, we document the phylogeography of the California endemic genus Promyrmekiaphila and its constituent species, which also includes P. clathrata and P. winnemem. Based on these data we show a pattern of strong geographic structuring among populations but cannot entirely discount recent gene flow among populations that are parapatric, particularly for deeply diverged lineages within P. clathrata. The genetic data, in addition to revealing a new undescribed species, also allude to a pattern of potential phenotypic differentiation where species likely come into close contact. Alternatively, phenotypic cohesion among genetically divergent P. clathrata lineages suggests that some level of gene flow is ongoing or occurred in the recent past. Despite considerable field collection efforts over many years, additional sampling in potential zones of contact for both species and lineages is needed to completely resolve the dynamics of divergence in Promyrmekiaphila at the population-species interface.

Influence of High-Frequency Ultrasonic Vibration Load on Pore-Fracture Structure in Hard Rock: A Study Based on 3D Reconstruction Technology.

Rock fracture is a macroscopic fracturing process resulting from the initiation and propagation of microscopic cracks. Therefore, it is crucial to comprehend the damage and fracture mechanism of rock under ultrasonic vibration by investigating the evolutionary pattern of the meso-pore fracture structure in response to high-frequency vibrational loads, as explored in this study. Standard red sandstone samples with a diameter of 50 mm and height of 100 mm were subjected to ultrasonic high-frequency vibration tests. NMR and CT scans were conducted on the rock samples at different stages of ultrasonic vibration excitation to obtain the corresponding transverse relaxation time (T2) spectra and CT scan images for each layer. The NMR test results revealed that smaller pores formed within the rock under high-frequency vibration loads, with a noticeable expansion observed in micropores. Three-dimensional reconstruction analysis based on two-dimensional CT images demonstrated an increase in pore count by 145.56%, 122.67%, and 98.87%, respectively, for the upper, middle, and lower parts of the rock after 120 s of ultrasonic vibration excitation; furthermore, the maximum pore volume increased by 239.42%, 109.16%, and 18.99%, respectively, for these regions during this period as well. These findings contribute towards a deeper understanding regarding the mechanisms underlying rock fragmentation when exposed to high-frequency vibrational loads.

In the Footsteps of the Silk Road: Czech-Kyrgyz Geo-environmental Project

Kyrgyzstan can be represented, geomorphologically-speaking, by a transect between the Fergana lowlands and the Tien Shan highlands and is an outstanding area for the study of paleoclimatic conditions relating to climatic changes. These changes have been crucial for the behaviour of past cultures in this area, especially due to the presence of the Silk Road. A Czech environmental team, covering geology, geomorphology, pedology, paleoecology, archaeobotany, malacology, osteology and many other disciplines, has been following up previous survey fieldwork undertaken in this area. Since 2021, the expeditions in the south-eastern Kyrgyzstan (Osh Region) have been aiming at the structure and settlement pattern development in the contact zone between the fertile Fergana basin and the steppe environment at the foothills of the Pamir-Alai and Tian-Shan Mountains, from prehistory until the present, including the material testimony of life on the ancient and medieval Silk Road. This work is a part of an agreement between the University of West Bohemia in Pilsen, the Osh State University and the Institute of History, Archaeology and Ethnology named after B. Dzamgyrchinov of the National Academy of Sciences of the Kyrgyz Republic. One of the major challenges of the ongoing geoarchaeological and palaeoecological research is to link climate changes and changes forced by human action with the transformation of settlement and landscape patterns.

Tire noise prediction based on transfer learning and multi-modal fusion

Vehicle traffic noise has become an important factor in urban noise pollution. With the increase in the number of new-energy vehicles, the current situation of tire/road noise as one of the main noise sources of automobiles is becoming increasingly prominent. Tire noise prediction is the basis for optimizing the design of low-noise tires, providing a reference basis for tire design with low-noise performance. This paper used deep learning methods to predict the noise performance of TBR radial tires. We obtained descriptive statistical features of tire structure and tread pattern images as input to the model, and used measured tire/road noise as output, then we constructed a multi-modal tire noise dataset. Comparing the prediction performance of three pre-trained transfer models such as Resnet18, VGG16, and Inception V3 on the tire pattern images, the Resnet18 had the best prediction effect. Resnet18 was selected as a feature extractor to extract image features, which fuse with the tire structural features at the feature level. The experiment constructed the TLMF-TRNP model to predict tire noise. The experimental results of the TLMF-TRNP model indicated that RMSE, MAE, and R2 were 0.1337, 0.0948, and 0.9864 respectively, achieving ideal prediction accuracy on a small-scale tire noise dataset and controlling the absolute error of the test tires within ±0.4 dB effectively. An accurate tire noise prediction model will provide a theoretical basis for tire design with low noise tires.

Cultural differences in the ICE-Group experience: Diaries of French and British antarctic winteroverers

Cultural differences may influence the psychosocial adaptation to prolonged isolation and confinement in extreme environments. Recent results showed that the temporal pattern of mood changes may also be affected by cultural differences. The aim of the study was to gain deeper insight into the structure and temporal patterns of group-related themes mentioned in the diaries of Antarctic winteroverers in two different stations with different national and organizational backgrounds. The diaries of the corresponding 8-8 French and British crew members of the Concordia and Halley VI research stations were subjected to content analysis. Method. A total of 18324 sentences were coded. In the first phase of the analysis, we identified 5 major thematic groups (Self focus, Group focus, Antarctica focus, Outworld focus, and Castoff sentences). One-third of these sentences were Group Focus, which were classified into 4 code groups, depending on whether the sentences referred to Experienced or Observed Comfort or Discomfort in the ingroup, respectively. These 4 code groups were subject to further analyses to test whether each code cluster showed a significant difference between British and French winteroverers during the 4 quarters of the mission. The Q3 phenomenon was also investigated. Results. Throughout all four quarters, the British crewmembers used significantly more Experienced Comfort sentences, while the French expressed significantly more Observed Discomfort sentences. Regarding the temporal patterns, the amount of Experienced Comfort sentences was significantly lower in the French diaries compared to the British diaries in the third quarter of the mission. Conclusions. Content analysis detected the impact of cultural differences on the composition and temporal pattern of social experiences of winterovering crews. It thus can diagnose and predict the psychodynamics of groups in isolated, confined, and extreme (ICE) environments, such as polar stations or long-duration missions in space.

Genome-Wide Identification and Expression Analysis Unveil the Involvement of the Cold Shock Protein (CSP) Gene Family in Cotton Hypothermia Stress.

Cold shock proteins (CSPs) are DNA/RNA binding proteins with crucial regulatory roles in plant growth, development, and stress responses. In this study, we employed bioinformatics tools to identify and analyze the physicochemical properties, conserved domains, gene structure, phylogenetic relationships, cis-acting elements, subcellular localization, and expression patterns of the cotton CSP gene family. A total of 62 CSP proteins were identified across four cotton varieties (Gossypium arboreum, Gossypium raimondii, Gossypium barbadense, Gossypium hirsutum) and five plant varieties (Arabidopsis thaliana, Brassica chinensis, Camellia sinensis, Triticum aestivum, and Oryza sativa). Phylogenetic analysis categorized cotton CSP proteins into three evolutionary branches, revealing similar gene structures and motif distributions within each branch. Analysis of gene structural domains highlighted the conserved CSD and CCHC domains across all cotton CSP families. Subcellular localization predictions indicated predominant nuclear localization for CSPs. Examination of cis-elements in gene promoters revealed a variety of elements responsive to growth, development, light response, hormones, and abiotic stresses, suggesting the potential regulation of the cotton CSP family by different hormones and their involvement in diverse stress responses. RT-qPCR results suggested that GhCSP.A1, GhCSP.A2, GhCSP.A3, and GhCSP.A7 may play roles in cotton's response to low-temperature stress. In conclusion, our findings underscore the significant role of the CSP gene family in cotton's response to low-temperature stress, providing a foundational basis for further investigations into the functional aspects and molecular mechanisms of cotton's response to low temperatures.

Genome-Wide Identification and Expression Analysis of Beta-Galactosidase Family Members in Chinese Bayberry (Myrica rubra)

Fruit development and softening play pivotal roles in determining fruit quality and post-harvest shelf life in Chinese bayberry (Myrica rubra). However, the specific role of beta (β)-galactosidase, particularly β-galactosidase of M. rubra (MrBGAL), in facilitating fruit softening remains unclear. In this study, we aimed to address this gap by investigating the involvement of MrBGALs genes in fruit softening. We identified all 15 MrBGALs and conducted a comprehensive analysis, including phylogenetic relationships, gene structure, protein motifs, co-linearity, and expression patterns. Using phylogenetic analysis, we classified all MrBGALs into five distinct groups. Additionally, cis-element prediction and comparative genome analysis provided insightful clues about the functionality of MrBGALs. Transcriptome data revealed unique expression patterns of MrBGALs throughout various fruit development stages. These findings introduce valuable candidate genes that can contribute to unraveling the functions and molecular mechanisms governing fruit development and softening in Chinese bayberry.

Patterns in the genetic structure of 49 lowland rain forest tree species co‐distributed on opposite sides of the northern Andes

AbstractThe Andes are a major dispersal barrier for lowland rain forest plants and animals, yet hundreds of lowland tree species are distributed on both sides of the northern Andes, raising questions about how the Andes influenced their biogeographic histories and population genetic structure. To explore these questions, we generated standardized datasets of thousands of SNPs from paired populations of 49 tree species co‐distributed in rain forest tree communities located in Panama and Amazonian Ecuador and calculated genetic diversity (π) and absolute genetic divergence (dXY) within and between populations, respectively. We predicted (1) higher genetic diversity in the ancestral source region (east or west of the Andes) for each taxon and (2) correlation of genetic statistics with species attributes, including elevational range and life‐history strategy. We found that genetic diversity was higher in putative ancestral source regions, possibly reflecting founder events during colonization. We found little support for a relationship between genetic divergence and species attributes except that species with higher elevational range limits exhibited higher dXY, implying older divergence times. One possible explanation for this pattern is that dispersal through mountain passes declined in importance relative to dispersal via alternative lowland routes as the Andes experienced uplift. We found no difference in mean genetic diversity between populations in Central America and the Amazon. Overall, our results suggest that dispersal across the Andes has left enduring signatures in the genetic structure of widespread rain forest trees. We outline additional hypotheses to be tested with species‐specific case studies.

Altitudinal patterns of alpine soil ammonia-oxidizing community structure and potential nitrification rate.

Nitrogen availability limits the net primary productivity in alpine meadows on the Qinghai-Tibetan Plateau, which is regulated by ammonia-oxidizing microorganisms. However, little is known about the elevational patterns of soil ammonia oxidizers in alpine meadows. Here, we investigated the potential nitrification rate (PNR), abundance, and community diversity of soil ammonia-oxidizing microorganisms along the altitudinal gradient between 3,200 and 4,200 m in Qinghai-Tibetan alpine meadows. We found that both PNR and amoA gene abundance declined from 3,400 to 4,200 m but lowered at 3,200 m, possibly due to intense substrate competition and biological nitrification inhibition from grasses. The primary contributors to soil nitrification were ammonia-oxidizing archaea (AOA), and their proportionate share of soil nitrification increased with altitude in comparison to ammonia-oxidizing bacteria (AOB). The alpha diversity of AOA increased by higher temperature and plant richness at low elevations, while decreased by higher moisture and low legume biomass at middle elevations. In contrast, the alpha diversity of AOB increased along elevation. The elevational patterns of AOA and AOB communities were primarily driven by temperature, soil moisture, and vegetation. These findings suggest that elevation-induced climate changes, such as shifts in temperature and water conditions, could potentially alter the soil nitrification process in alpine meadows through changes in vegetation and soil properties, which provide new insights into how soil ammonia oxidizers respond to climate change in alpine meadows.IMPORTANCEThe importance of this study is revealing that elevational patterns and nitrification contributions of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) communities were primarily driven by temperature, soil moisture, and vegetation. Compared to AOB, the relative contribution of AOA to soil nitrification increased at higher elevations. The research highlights the potential impact of elevation-induced climate change on nitrification processes in alpine meadows, mediated by alterations in vegetation and soil properties. By providing new insights into how ammonia oxidizers respond to climate change, this study contributes valuable knowledge to the field of microbial ecology and helps predict ecological responses to environmental changes in alpine meadows.

Sex-specific modulation of early life vocalization and cognition by Fmr1 gene dosage in a mouse model of Fragile X Syndrome

BackgroundPup-dam ultrasonic vocalizations (USVs) are essential to cognitive and socio-emotional development. In autism and Fragile X Syndrome (FXS), disruptions in pup-dam USV communication hint at a possible connection between abnormal early developmental USV communication and the later emergence of communication and social deficits.MethodsHere, we gathered USVs from PND 10 FXS pups during a short period of separation from their mothers, encompassing animals of all possible genotypes and both sexes (i.e., Fmr1-/y vs. Fmr1+/y males and Fmr1+/+, +/-, and -/- females). This allowed comparing the influence of sex and gene dosage on pups’ communication capabilities. Leveraging DeepSqueak and analyzing vocal patterns, intricate vocal behaviors such as call structure, duration, frequency modulation, and temporal patterns were examined. Furthermore, homing behavior was assessed as a sensitive indicator of early cognitive development and social discrimination. This behavior relies on the use of olfactory and thermal cues to navigate and search for the maternal or nest odor in the surrounding space.ResultsThe results show that FMRP-deficient pups of both sexes display an increased inclination to vocalize when separated from their mothers, and this behavior is accompanied by significant sex-specific changes in the main features of their USVs as well as in body weight. Analysis of the vocal repertoire and syntactic usage revealed that Fmr1 gene silencing primarily alters the USVs’ qualitative composition in males. Moreover, sex-specific effects of Fmr1 silencing on locomotor activity and homing behavior were observed. FMRP deficiency in females increased activity, reduced nest-reaching time, and extended nest time. In males, it prolonged nest-reaching time and reduced nest time without affecting locomotion.ConclusionsThese findings highlight the interplay between Fmr1 gene dosage and sex in influencing communicative and cognitive skills during infancy.

Population genetics reveals new introgression in the nucleus herd of min pigs.

Min pigs are a unique genetic resource among local pig breeds in China. They have more excellent characteristics in cold and stress resistance, good meat quality, and a high reproductive rate. However, the genetic structure and driving factors remain unclear in the nucleus herd. In this study, the genetic diversity of Min pigs was studied to reveal the formation mechanism of its unique genetic structure. We hope to protect and develop the genetic resources of Min pigs. We analyzed different types of genes to identify the genetic structure and gene introgression pattern of Min pigs. The nuclear DNA dataset includes information on 21 microsatellite loci and 6 Y-chromosome genes, and the mitochondrial D-loop gene is selected to represent maternal lineages. The above genes are all from the nucleus herd of Min pigs. The results of genetic structure identification and analysis of potential exogenous gene introgression patterns indicate that the nucleus herd of Min pigs maintains a high level of genetic diversity (polymorphism information content = 0.713, expected heterozygosity = 0.662, observed heterozygosity = 0.612). Compared with other Asian pig breeds, the formation of Min pig breeds is more special. Gene introgression from European pig breeds to Min pigs has occurred, which is characterized by complete introgression of paternal genes and incomplete introgression of maternal genes. Gene introgression caused by cross-breeding is not the main factor leading to the formation of the current genetic structure of Min pigs, but this process has increased the level of genetic diversity in the nucleus herd. Compared with the influence of gene introgression, our research suggest that artificial selection and environmental adaptive evolution make Min pigs form unique genetic characteristics.