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Several sources of repeating coherent bursts of radio emission with periods of many minutes have now been reported in the literature. These 'ultralong period' (ULP) sources have no clear multiwavelength counterparts and challenge canonical pulsar emission models, leading to debate regarding their nature. In this work, we report the discovery of a bright, highly polarized burst of radio emission at low Galactic latitude as part of a wide-field survey for transient and variable radio sources. ASKAP J175534.9 |$-$| 252749.1 does not appear to repeat, with only a single intense two-minute |$\sim$| 200-mJy burst detected from 60 h of observations. The burst morphology and polarization properties are comparable to those of classical pulsars but the duration is more than one hundred times longer, analogous to ULPs. Combined with the existing ULP population, this suggests that these sources have a strong Galactic latitude dependence and hints at an unexplored population of transient and variable radio sources in the thin disc of the Milky Way. The resemblance of this burst with both ULPs and pulsars calls for a unified coherent emission model for objects with spin periods from milliseconds to tens of minutes. However, whether or not these are all neutron stars or have the same underlying power source remains open for debate. [ABSTRACT FROM AUTHOR]

During the 2013 SSW, ionospheric disturbances were observed at eighteen stations on three meridional chains of 100°E, 110°E and 120°E ranging from 19.03°N to 49.21°N at latitudes over the East Asia region. The total electron content (TEC) response showed evident semidiurnal disturbances with TEC enhancement in the morning and depletion in the afternoon. The maximum TEC increased by more than 220 % along the 120°E longitude. In addition, the semidiurnal disturbance of the TEC was enhanced and indicated evident latitudinal and longitudinal dependence. The wavelet spectra of semidiurnal disturbance in TEC presented quasi-16-day planetary wave-like oscillations at middle latitudes and quasi-10-day planetary wave-like oscillations near Sanya at low latitudes. Moreover, the zonal winds and meridional winds at altitudes of 92 km and 96 km showed quasi-16-day planetary waves at the Mohe station located at middle latitudes and quasi-10-day planetary waves at the Sanya station located at low latitudes, which maybe relate to the semidiurnal disturbance of the TEC. In particular, the 12hrs oscillation of the TEC showed a quasi-16-day periodic component at middle latitudes and a quasi-10-day periodic component at low latitudes, indicating that the modulated semidiurnal tides may transmit these 10-day and 16-day planetary wave-like oscillations to the ionosphere. The coupling between the atmosphere and ionosphere may be strengthened by quasi-16-day waves at middle latitudes and quasi-10-day waves at low latitudes (near Sanya). This finding can further confirm the PW-tide interaction theory during the 2013 SSW event, and it is of significance in the middle and low latitude ionospheric response to SSW. [ABSTRACT FROM AUTHOR]

• Three TEC techniques gave consistent values of shell height over East Africa. • New method suggested agree with that of Nava et al.,. (2007) and Li et al.,. (2017). • Over East Africa the value of the effective height is about 400 km. The ionosphere over the low latitude region, where East Africa falls, is associated with high perturbations arising from numerous phenomenon such as Equatorial Ionization Anomaly (EIA), plasma bubbles, electrostatic instabilities etc. All these together, make it difficult to determine the actual values of important parameters used to characterize the ionosphere of the region in order to mitigate its negative contribution to technology. One such parameter is the effective height which is used among others to map the Total electron Content (TEC) over a given region, in argumentation, calibration of Global Navigation Satellite System (GNSS) observations etc. The value of the effective height of a place is got by radiosounders installed in a given location. However, these sounders are not readily available in many places, especially East Africa where the few that are available are currently malfunctioning and also their ionospheric spatial coverage is very limited. Alternative techniques that use TEC from GNSS receivers to estimate effective height of the ionosphere have been suggested and employed in different places, giving results that in some instances conflict with each other. This study has done a comparative analysis of the suggested GNSS-TEC techniques to determine their reliability over low latitude region of East Africa and has found out that some of them do not give consistent results over the region. To supplement the existing methods, a new method is proposed that relates IRI TEC to TEC obtained from the difference between sTEC recorded simultaneously by a given receiver on ground and the receiver on board Swarm satellite when swarm is over head the ground receiver. The results obtained using the new suggested technique gives consistent results over East African region which is in agreement with two other techniques among the four methods discussed. [ABSTRACT FROM AUTHOR]

Abundant proxy records suggest a profound reorganization of the Atlantic Meridional Overturning Circulation (AMOC) during the Last Glacial Maximum (LGM, ~21,000 y ago), with the North Atlantic Deep Water (NADW) shoaling significantly relative to the present-day (PD) and forming Glacial North Atlantic Intermediate Water (GNAIW). However, almost all previous observational and modeling studies have focused on the zonal mean two-dimensional AMOC feature, while recent progress in the understanding of modern AMOC reveals a more complicated three-dimensional structure, with NADW penetrating from the subpolar North Atlantic to lower latitude through different pathways. Here, combining 231Pa/230Th reconstructions and model simulations, we uncover a significant change in the three-dimensional structure of the glacial AMOC. Specifically, the mid-latitude eastern pathway (EP), located east of the Mid-Atlantic Ridge and transporting about half of the PD NADW from the subpolar gyre to the subtropical gyre, experienced substantial intensification during the LGM. A greater portion of the GNAIW was transported in the eastern basin during the LGM compared to NADW at the PD, resulting in opposite 231Pa/230Th changes between eastern and western basins during the LGM. Furthermore, in contrast to the wind-steering mechanism of EP at PD, the intensified LGM EP was caused primarily by the rim current forced by the basin-scale open-ocean convection over the subpolar North Atlantic. Our results underscore the importance of accounting for three-dimensional oceanographic changes to achieve more accurate reconstructions of past AMOC. [ABSTRACT FROM AUTHOR]

The BeiDou Global Navigation Satellite System (BDS‐3) has been providing global positioning, navigation, and timing (PNT) services for over 3 years. Single‐frequency single point positioning (SPP) receivers have significant advantages such as low hardware cost and easy implementation, making them widely used in engineering practice. The time group delay (TGD) and intersignal correction (ISC) are the main parameters for single‐frequency SPP and must be corrected. On‐orbit 30 BDS‐3 satellites have upgraded and maintained operation in 2022, while more multi‐GNSS experiment (MGEX) stations can simultaneously receive all five frequency civilian signals of BDS‐3, namely, B1I, B1C, B2a, B2b, and B3I. So now, it is worth assessing the SPP of BDS‐3 five single‐frequency civilian signals considering TGD and ISC corrections, respectively. Then, with 7 days of 73 MGEX stations simultaneously receiving all BDS‐3 five frequencies, GPS L1 and Galileo E1 civilian signals were selected, and the root mean square (RMS) error was used to assess the SPP performance. The BDS‐3 single‐frequency SPP static and kinematic results show that the order of accuracy from high to low is B1C, B1I, B3I, B2b, and B2a. More thorough static results reveal that B1C's RMS errors in the north, east, and up (NEU) three directions are 1.12, 0.41, and 1.78 m, respectively, and B1C outperforms B2a by 0.85, 0.28, and 1.23 m. More detailed kinematic results reveal that B1C's NEU RMS errors are 1.47, 0.77, and 2.72 m, respectively, and that B1C outperforms B2a by 1.04, 0.47, and 1.78 m. The single‐frequency SPP has a higher positioning accuracy at mid to high latitudes in the northern hemisphere than at mid to low latitudes in the southern. The single‐frequency SPP of BDS‐3 B1I is competitive with GPS L1 and Galileo E1. BDS‐3's five single‐frequency signals, GPS L1, and Galileo E1 all perform well in the east direction, while the up direction performs badly in static and kinematic modes. [ABSTRACT FROM AUTHOR]

Background and Aims Amphistomy is a potential method for increasing photosynthetic rate; however, the latitudinal gradients of stomatal density across amphistomatous species and their drivers remain unknown. Methods Here, the adaxial stomatal density (SDad) and abaxial stomatal density (SDab) of 486 amphistomatous species–site combinations, belonging to 32 plant families, were collected from China, and their total stomatal density (SDtotal) and stomatal ratio (SR) were calculated. Key Results Overall, these four stomatal traits did not show significant phylogenetic signals. There were no significant differences in SDab and SDtotal between woody and herbaceous species, but SDad and SR were higher in woody species than in herbaceous species. Besides, a significantly positive relationship between SDab and SDad was observed. We also found that stomatal density (including SDab, SDad and SDtotal) decreased with latitude, whereas SR increased with latitude, and temperature seasonality was the most important environmental factor driving it. Besides, evolutionary history (represented by both phylogeny and species) explained ~10- to 22-fold more of the variation in stomatal traits than the present-day environment (65.2–71.1 vs. 2.9–6.8 %). Conclusions Our study extended our knowledge of trait–environment relationships and highlighted the importance of evolutionary history in driving stomatal trait variability. [ABSTRACT FROM AUTHOR]

The prenatal transfer of testosterone (T) from mother to offspring is an important source of phenotypic plasticity. In birds, exposure to ecologically relevant stimuli, such as social competition or an attractive mate, can cause females to deposit more T into their egg yolks. Exposure to elevated yolk T can modify the expression of several fitness‐related traits in offspring (e.g. growth, immune function, secondary sex traits and behaviour). Despite some of these changes being potentially adaptive, not all studies find that yolk T levels change in response to ecologically relevant stimuli. This heterogeneity is currently unexplained, limiting our ability to predict inter‐generational responses to ecological change.Here, we performed a systematic literature search and found 119 observations across 39 wild species that measured inter‐female variation in yolk T allocation in response to various stimuli. We used boosted regression trees, a form of machine learning, to examine whether species‐specific traits or variation in study‐level variables could explain variation in yolk T allocation (i.e. statistically significant vs. non‐significant responses).We found that both species‐specific traits and study‐level variables are important predictors of significant changes in yolk T levels. Geographic range (latitude and longitude), evolutionary distinctiveness, longevity, egg mass relative to female mass, sociality, migration status and time to fledge were among the top 10 most influential predictors of the 48 examined. We also found that studies measuring or manipulating social stimuli (e.g. competition and breeding density) or breeding date were more likely to detect changes in yolk T allocation compared with studies examining other ecological contexts.Overall, these data provide several testable hypotheses concerning yolk T allocation and its adaptive value across species and contexts. Additionally, these findings can help us predict how ecological changes will affect hormonal responses in females that can shape future generations. [ABSTRACT FROM AUTHOR]

Climatological monthly mean tropical cyclone (TC) genesis location in the western North Pacific exhibits a marked meridional shift from June to November and the physical cause of such a shift was investigated through the diagnosis of observational and reanalysis datasets. Two genesis potential indices were used to examine key environmental parameters affecting the meridional shift. The diagnosis results indicate that dynamic parameters such as vertical and meridional wind shears play a dominant role in promoting both the northward advance and southward retreat of the mean genesis latitude, while the effect of vertical velocity is negligible. The thermodynamic parameters such as relative humidity and potential intensity in general play a minor role, except that the latter helps promote northward advance during the early TC season. The change of the environmental parameters is closely linked to the sub‐seasonal evolution of the monsoon trough and subtropical high in the western North Pacific. Maximum synoptic‐scale variability also experiences a similar meridional shift, contributing to the TC genesis location shift. [ABSTRACT FROM AUTHOR]

Biogeographical patterns explain variation in body size, although the strength and directions of these patterns vary. When researchers account for the micro- or macrohabitats that species inhabit, they often find that biogeographical relationships with body size are modified, especially in taxa that inhabit diverse environments. Freshwater crayfishes are an ideal group in which to study the interaction between habitat, biogeography, and body size, because there are >700 crayfishes that inhabit aquatic environments, semi-terrestrial burrows, and caves. Here, we explore evolution of body size across 452 species of crayfish by considering the interaction between their habitats (aquatic, semi-terrestrial/aquatic, semi-terrestrial, and cave-dwelling) and the mean temperature of their geographical range. We documented 64-fold variation in body length. Aquatic species were the largest and had the greatest variation in body size. Crayfishes that inhabit both semi-terrestrial and aquatic habitats exhibit a weak negative relationship between body size and environmental temperature; solely aquatic species reverse this relationship. Evolutionarily, our ancestral reconstruction suggests that the ancestral crayfish was an aquatic species with a body length of 81.1 mm, which aligns with data from fossil crayfish. Overall, our study highlights how uniting biogeographical and evolutionary approaches improves our ability to explore patterns of animal body size and unearth explanatory mechanisms. [ABSTRACT FROM AUTHOR]

Aim: Global warming has highlighted the importance of understanding the role of thermal tolerance as a driver of species distributions, especially for ectotherms. Here we analyse interactions between latitude, elevation and arboreality as predictors of geographic patterns of thermal tolerance in ants. Location: The collected data are distributed globally. Methods: We first tested the effect of latitude, elevation and its interactive effect on ant CTmax and CTmin. Second, we tested whether CTmax and CTmin are phylogenetic clustering. Finally, we tested whether CTmax and CTmin can be explained by nesting microhabitat (ground vs. tree‐nesting species) and whether the probability of occurrence of tree‐nesting species along thermal gradients helps explain the global pattern in ant CTmax. Results: CTmax and CTmin displayed high and low phylogenetic signals respectively and therefore showed different responses to geographic gradients. Notably, we found that CTmax was higher in higher latitudes. This was explained by a lack of elevational turnover at high latitudes among tree‐nesting species, which are exposed to warmer microclimates and have higher CTmax compared with ground‐nesting species. CTmin decreased with elevation at low latitudes, but did not vary with elevation at higher latitudes. Main Conclusions: Our findings highlight the important influence of arboreality on the macroecology of thermal tolerance, substantially modifying traditional notions of variation along latitudinal and elevation gradients. [ABSTRACT FROM AUTHOR]

Deterministic factors including homogeneous and heterogeneous selection and stochastic factors jointly shape ecological communities. However, a quantitative synthesis of the factors underlying the balance among different assembly processes is lacking. Here, we synthesized data from 149 datasets covering major biotic groups and ecosystem types globally. We used a null model approach based on Raup–Crick dissimilarities and Bayesian meta‐regression to analyze the data. We found that communities were more under homogeneous selection than heterogeneous selection across biotic taxa and ecosystems. Environment selected species homogeneously more often at small scales while heterogeneously more often at large scales. Stochasticity also showed scale‐dependence as stochastic community assembly increased with study scale. Homogeneous and heterogeneous selection were strongest at high latitudes while stochastic factors were strongest in tropics. Marine systems had the highest degree of homogeneous selection and the lowest stochasticity. We provide the first analysis of community assembly across taxa and ecosystems which should be important for a better understanding of how communities respond to environmental change. [ABSTRACT FROM AUTHOR]

Low temperatures are a key factor affecting the growth, development, and geographical distribution of prickly ash. This study investigated the impact of ecological and geographical factors on the freezing tolerance of prickly ash germplasm. Thirty-seven germplasm samples from 18 different origins were collected, and their freezing tolerance was comprehensively evaluated. The correlation between freezing tolerance and the ecological and geographical factors of their origins was also analyzed. Significant differences in freezing tolerance were observed among germplasm from different origins. The semi-lethal temperature of the germplasm ranged from − 12.37 to 1.08 °C. As temperatures decreased, the relative conductivity (REC) and catalase (CAT) activity of the germplasm gradually increased, while soluble sugar (SS), soluble protein (SP), free proline (Pro), and Peroxidase (POD) activities decreased and then increased. Superoxide dismutase (SOD) activity initially increased and then decreased. A comprehensive evaluation of freezing tolerance was conducted using a logistic equation, membership function, and cluster analysis. Germplasm from Tongchuan and Hancheng (Shaanxi Province, China), Asakura (Japan), and Yuncheng (Shanxi Province, China) exhibited the highest freezing tolerance, whereas those from Rongchang (Chongqing Municipality, China), Qujing (Yunnan Province, China), and Honghe (Yunnan Province, China) had the lowest. The correlation analysis revealed a significant positive correlation between freezing tolerance and latitude, and a significant negative correlation with the temperature of origin. Germplasm from higher latitudes showed higher SS content, SOD and CAT activities, stronger antioxidant enzyme activity, and better freezing tolerance compared to those from lower latitudes. REC was lower in germplasm originating from low-temperature areas than in those from high-temperature areas. Additionally, SP, Pro content, SOD, and POD activities were higher, indicating effective scavenging of active oxygen free radicals. No significant correlation was found between altitude and longitude of origin and freezing tolerance. However, at similar latitudes, prickly ash from higher altitudes displayed higher antioxidant enzyme activity and stronger freezing tolerance compared to those from lower altitudes. These findings provide a scientific basis for breeding prickly ash cultivars suited to different ecological regions. [ABSTRACT FROM AUTHOR]

Aim: Long‐standing theory predicts that the intensity of biotic interactions increases from high to low latitudes. Studies addressing geographic variation in predation on insect prey have often relied on prey models, which lack many characteristics of live prey. Our goals were to explore global latitudinal patterns of predator attack rates on standardised live insect prey and to compare the patterns in predation on live insects with those on plasticine prey models. Location: Global forested areas. Time Period: 2021–2023. Major Taxa: Arthropods, birds. Methods: We measured predation rates in 43 forested locations distributed across five continents from 34.1° S to 69.5° N latitude. At each location, we exposed 20 sets of three bait types, one set per tree. Each set included three live fly larvae (maggots), three live fly puparia and three plasticine models of the puparia. We used glue rings to isolate half of the sets from non‐flying predators. Results: Arthropod attack rates on plasticine prey decreased linearly from low to high latitudes, whereas attack rates on maggots had a U shaped distribution, with the lowest predation rates at temperate latitudes and the highest rates at tropical and boreal latitudes. This difference emerged from intensive predator attacks on live maggots, but not on plasticine models, in boreal sites. Site‐specific attack rates of arthropod predators on live and plasticine prey were not correlated. In contrast, bird attack rates on live maggots and plasticine models were positively correlated, but did not show significant latitudinal changes. Main Conclusions: Latitudinal patterns in predation differ between major groups of predators and between types of prey. Poleward decreases in both arthropod and combined arthropod and bird predation on plasticine models do not mirror patterns of predation on our live prey, the latter likely reflecting real patterns of predation risk better than do patterns of attack on artificial prey. [ABSTRACT FROM AUTHOR]

Understanding the impact that climate had in shaping cranial variation is critical for inferring the evolutionary mechanisms that played a role in human diversification. Here, we provide a comprehensive study aiming to analyze the association between climate and cranial variation of high latitude populations living in temperate to cold environments of Asia, North America, and South America. For this, we compiled a large morphometric dataset (N = 2633), which was combined with climatic and genomic data. We tested the influence of climate on the facial skeleton, nasal protrusion, and cranial vault and through multiple statistical tests at two geographical scales: intracontinental and intercontinental. We show that populations living in cold areas share a morphological pattern characterized by an increase in nasal height, facial and orbital heights and widths, a decrease in facial protrusion, and larger, longer, and lower cranial vaults. There are also distinctive features; populations from north Asia present the tallest noses, largest faces, and cranial vaults of the whole sample. Nasal breadth dimensions show small values in Asians, large values in South Americans, and non‐significant changes in arctic North America. The morphological pattern in populations living at high latitude may be the result of parallel adaptation, as supported by physiological, morphometric, ecological, and genetic explanations, while the differences in magnitude and phenotypic expression could be due to the diverse population histories, severity of climate, and cultural strategies. Overall, our study shows that climate is a relevant factor shaping modern human morphology and it should be considered when studying modern human evolution and diversification. [ABSTRACT FROM AUTHOR]

Past studies have shown a significant observed poleward trend in the latitude at which tropical cyclones reach their lifetime maximum intensity (LMI), especially in the northwest Pacific basin. Given the brevity of the historical record, it remains difficult to separate the forced trend from internal variability of the climate system. A recently developed tropical cyclone downscaling model is used to downscale the Community Earth System Model, version 2 (CESM2), preindustrial control simulation. It is found that the observed trend in the latitude at which tropical cyclones reach their LMI in the northwest Pacific is very unlikely to be caused by internal variability. The same downscaling model is then used to downscale CESM2 simulations under historical forcing. The resulting trend distribution shows a significant poleward migration of tropical cyclone LMI even after regressing out both natural variability and the part of the forced warming pattern that projects onto natural variability. The results indicate that the observed poleward migration of the latitude at which tropical cyclones reach their LMI in the northwest Pacific basin is likely to be, at least in part, forced. However, the magnitude of the projected poleward trend in climate models can be significantly modulated by the simulated spatial pattern of ocean warming. This highlights how discrepancies between models and observations, with regard to projected changes to the equatorial zonal sea surface temperature gradient under anthropogenic forcing, can lead to large uncertainties in projected changes to the LMI latitude of tropical cyclones. Significance Statement: Observations in the northwest Pacific basin show that the latitude at which tropical cyclones are at their most intense has been trending northward in the recent half century. These changes are important since tropical cyclones could bring hazardous weather to coastal areas that are poorly equipped to handle them. Here, we show that natural variations in Earth's climate are very unlikely to explain the observed poleward trend in the latitude that tropical cyclone reach their maximum intensity. We find that it is much more likely that the observed trend is forced by human-related emissions, though the spatial pattern of warming in response to greenhouse emissions can have significant impacts on the magnitude of the trend. [ABSTRACT FROM AUTHOR]

Immunosuppression after solid organ transplantation is associated with an increased risk of keratinocyte carcinoma (KC). Despite its established morbidity, KC risk in liver transplant (LT) recipients is understudied, including the contribution of immunosuppression regimen and latitude. A retrospective cohort of 9,966 adult first LT alone recipients alive with their native allograft at 1-year post-LT without prior KC between 2007 and 2016 were identified using linked data from the Organ Procurement and Transplantation Network and Medicare administrative claims. The primary exposures were immunosuppression regimen and latitude of residence. The primary outcome was incident, de novo KC occurring at least 1-year after LT. Adjusted Cox regression analysis stratified by transplant center was used in all analyses. The cohort was 63.4% male, 70.2% White and with median age 61 years (interquartile range, IQR, 54–66) at transplant. Calcineurin inhibitor (CNI) with anti-metabolite combination was independently associated with incident KC when measured as intention-to-treat (adjusted hazard ratio (aHR) 1.21 vs. CNI monotherapy, 95% CI 1.02–1.43, p = 0.026), in a time-updating as-treated analysis (aHR 1.61, 95% CI 1.34–1.93; p < 0.001) and when measured as cumulative exposure (aHR 1.13 per 6-month increase, 95% CI: 1.02–1.33; p = 0.027). More southern latitude of residence was also independently associated with incident KC with an aHR of 1.26 per 5°N decrease towards the Equator (95% CI: 1.08–1.47, p = 0.003). We demonstrate independent effects of CNI with antiM immunosuppression regimen and latitude of residence on the risk of post-LT KC, which will better inform screening practices and immunosuppression management. [ABSTRACT FROM AUTHOR]

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In this study, we propose a method to predict the classification of the eruption plume types: "strong plumes" and "weak plumes". Our method reproduces the general features that the eruption plume types depend on, both the meteorological conditions and eruption conditions, and successfully reproduces the classification of the plume types for historical eruption events. Application of the method to Monte Carlo simulations revealed that eruption plumes at a low latitude tend to form strong plumes due to weak ambient winds, whereas eruption plumes at a mid latitude tend to form weak plumes due to the strong ambient winds associated with the jet stream. The simulation also revealed that mid‐latitude eruption plumes tend to be strong plumes in the summer when ambient winds are lowered by a weakening and poleward movement of the jet stream. Plain Language Summary: When an explosive volcanic eruption occurs, an eruption plume rises up to a few kilometers or tens of kilometers while incorporating ambient air. After the plume density equals to that of the atmosphere, the plume intrudes horizontally into the stratified atmosphere. This intrusion is classified into mainly two types: a radial spreading type (i.e., strong plume, often called an "umbrella cloud") and a downwind spreading type (i.e., weak plume). Estimation of the intrusion type is vital to forecast ash dispersal, because an input parameter for ash dispersal calculation depends on the intrusion type. In this study, we introduce a method to predict the plume intrusion type, and we validated the method for 14 historical eruptions. In addition, to investigate the relationship between the intrusion type and meteorological conditions at the volcano's location, we conducted Monte Carlo simulations with random eruption intensities and actual long‐term meteorological data. The simulation results revealed the following trends: (a) eruption plumes at a low latitude tend to be a radial spreading type, and (b) eruption plumes at mid latitudes tend to be a downwind spreading type except during the summer. These features can be understood from the meteorological conditions at the volcano's location. Key Points: A method to predict an eruption plume type ("strong plume" or "weak plume") is introducedEruption plumes at low‐latitudes tend to be strong plumes, because ambient winds at high altitude are weakStrong wind associated with jet stream at mid latitude affects eruption plumes, favoring weak plumes in all seasons except summer [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Methods Results Main Conclusions The enemy release hypothesis states that the invasion success of non‐native species is partly due to their escape from natural enemies, e.g., herbivores. Large‐scale studies of herbivory using multiple species across multiple sites are needed to test the generality of herbivory release in non‐native plants.Europe.We carried out leaf‐herbivory surveys from 2007 to 2021 in 15 botanical gardens ranging in latitude from 47°N (Switzerland) to 63°N (Norway) to investigate how herbivory levels differed between (i) native and non‐native species, and (ii) native and non‐naturalised or naturalised species.Overall, we found that herbivory levels were lower on non‐native than native species. In addition, we found that non‐naturalised plants suffered less herbivory than natives and that naturalised plants showed similar levels of herbivory to native plants.We find broad support for lower herbivory of non‐native plant species compared to natives. However, the stronger reduction in herbivory for non‐naturalised plants suggests that herbivore release may be transient and less pronounced for naturalised non‐native species that have become abundant and integrated into resident communities. This has implications for the management of naturalised non‐native plants, which are performing well in their non‐native ranges despite suffering comparable herbivory levels to native species. [ABSTRACT FROM AUTHOR]

Although some studies have explored the role of meteorological factors in the development of tuberculosis (TB), the majority have been confined to single regions, leading to inconsistent findings. Consequently, we conducted a multi-city study not only to determine whether meteorological factors significantly influence the risk of developing TB but also to assess the magnitude of these effects and explore potential modifying factors. Data on daily reported TB cases and meteorological factors were collected from January 1, 2013, to December 31, 2022, across 11 cities in Zhejiang Province. A distributed lag non-linear model using a quasi-Poisson distribution was employed. Multivariate meta-regression was used to obtain overall pooled estimates and assess heterogeneity. From 2013 to 2022, 267,932 TB cases were reported in Zhejiang Province. Notably, a nonlinear relationship was observed between temperature and TB, with the relative risk (RR) peaking at 1.0 °C (RR = 1.882, 95% CI 1.173–3.020). The effect of low temperature was immediate and significant for a 13-day lag period, with the maximum effect at lag0 (RR = 1.014, 95% CI 1.008–1.021). The exposure-response curve between relative humidity (RH) and TB exhibited an M-shape, with the RR peaking at 47.7% (RR = 1.642, 95% CI 1.044–2.582). The lag effect of low RH was significant at lag 25–59, with the highest RR observed at lag 32 (RR = 1.011, 95% CI 1.001–1.022). Gross domestic product (GDP) per person, population density, and latitude demonstrated significant modification effects. Our study showed that low temperature and RH were associated with an increased risk of TB. Additionally, GDP per person, population density, and latitude may play important roles in explaining the association between RH and TB. These findings provide scientific evidence for the development of geographically specific public health policies. [ABSTRACT FROM AUTHOR]

ABSTRACT Fieldwork investigations and stratigraphic analyses in the Parnaíba Basin, northern Brazil, reveal the interaction of the uppermost part of the Triassic Sambaíba aeolian dune field (erg) system with the latest Triassic–earliest Jurassic Mosquito lava flows. The lava flows originated as part of the Central Atlantic Magmatic Province (CAMP, ~201 Ma) and covered the aeolian system, allowing almost complete preservation of large‐scale in situ aeolian bedforms, even preserving lee‐ and stoss‐side. During the emplacement, the lava flows interacted with unconsolidated aeolian sediment, generating sediment–lava deformation features that are preserved at the interface between these units. This occurrence attests to arid conditions in the low latitudes of Gondwana at the Triassic–Jurassic transition. [ABSTRACT FROM AUTHOR]

In this paper, we conducted an analysis of the heliospheric current sheets (HCSs) in the heliosheath (HS), utilizing observations by Voyager 2 between 2008 and 2018. Employing rigorous criteria, we identified a total of 34 HCSs that indicate significant changes in magnetic polarity. These occurrences were more prevalent during solar maximum periods when the HCS expanded to higher latitudes, coinciding with the spacecraft positioned at an average latitude of −31° from the solar equator. We determined certain features of the large-scale structures of the identified HCSs. Most importantly, employing two distinct methods indicates that the thickness of the HCSs within the HS ranges from ∼0.003 to ∼0.4 au with an average thickness of ∼0.03 to ∼0.1 au, depending on methods of event selection and fitting techniques. This thickness surpasses that known near 1 au or other heliospheric distances. It is also notably thicker than the typical proton inertial length, implying unfavorable conditions for magnetic reconnection. Additionally, our analysis reveals a frequent tilt of HCS planes relative to the solar equatorial plane by a varying angle up to several tens of degrees, likely implying a common occurrence of a warped structure of the HCS within the HS. Longitudinally, the HCS planes closely align with the Parker spiral field direction expected in the HS. Finally, for a large fraction of the identified HCS events, the HCS planes are likely characterized by a rotational discontinuity. These findings are valid within the limits of the 1 hr resolution data used in this study. [ABSTRACT FROM AUTHOR]

Marine microbial eukaryotes (protists) perform essential metabolic functions in oceanic ecosystems. The diversity of protist functions remains poorly understood as few species have been isolated in laboratory settings. Metatranscriptomes provide an invaluable tool for exploring protist diversity and genetic capacities within their natural habitats. Here, we introduce the North Pacific Eukaryotic Gene Catalog, a compilation of metatranscriptome data derived from a total of 261 metatranscriptomes: 169 metatranscriptomes were derived from samples collected on three meridional surface transects along 158°W, each spanning ~20 degrees of latitude from the North Pacific Subtropical Gyre (NPSG) to the North Pacific Transition Zone (NPTZ); 92 metatranscriptomes were derived from two diel-resolved field studies, one in the NPSG at 157°W, 23°N, one in the NPTZ at 158°W, 41°N. The metatranscriptome sequences were de novo assembled into 175 assemblies and pooled into five datasets each containing between 22 M and 49 M contigs clustered at 99% protein identity. Assemblies were annotated by taxonomy and function, and enumerated by short read alignment. All data are available in the Zenodo repository, with underlying code available on github. [ABSTRACT FROM AUTHOR]

This study analyzes the characteristics of near-surface atmospheric CO2 concentrations on the southern slope of Tomur Peak from 2013 to 2022. Utilizing the Boughton two-parameter algorithm, we determined the CO2 background and non-background concentrations. Additionally, the Hysplit model was employed to investigate the potential contributing areas of the CO2 non-background concentration. Our findings that the CO2 concentration in the study area was approximately 17% lower than the global average, with an annual growth rate that was only about 47% of the global rate. The CO2 non-background concentration accounted for only 6.25% of the observed concentration, but was largely unaffected by near-ground meteorological factors. The source of the CO2 non-background was mainly controlled by the westerly belt, with potential source area mainly located in Central Asia. However, the WPSCF values in the modern ice and snow distribution area south of Tomur Peak and west of the monitoring station were significantly elevated, suggesting a strong wind transport of CO2 after accumulation under the influence of the elevated terrain. The local supplying path accounted for only 12.87%, indicating that human activities in the oasis areas of the Tarim Basin had a limited influence on the study area. Due to the blocking effect of the Baikal high-pressure system and the towering topography of the Tianshan Mountains, the influence of human emissions from higher latitudes was likely negligible. [ABSTRACT FROM AUTHOR]

ABSTRACT Diurnal roosts are vital to bats and growing evidence suggests that bats increasingly exploit synanthropic structures, such as buildings. The use of synanthropic roosts (SRs) has been explained as a consequence of the decreased availability of natural roosts imposed by habitat destruction, although growing evidence suggests that the use of SRs may be beneficial to bats in many ways, including enabling the expansion of distributional ranges. Based on data from Europe and North America, our study aimed to (1) analyse the proportion of use of synanthropic vs. natural roosts, (2) test the hypothesis that bats are forced to use SRs in response to the destruction of natural habitats, (3) analyse latitudinal variation of the proportion of use of SRs and (4) address the highly contrasting pattern in the proportion of use of SRs between the two continents in the light of historical aspects of coexistence between bats and humans. We compiled published data on day roosts obtained by means of radio‐telemetry, providing unbiased evidence of the proportion of synanthropic and natural roosts. We compared the obtained patterns between the two continents, analysed the relationship between the proportion of use of SRs, land cover and latitude and analysed historical reconstruction of anthropogenic land use. In Europe (n = 3385 roosts), SRs were used by twice more (26) bat species and were used 17× more frequently than in North America (n = 6795). We found no support for the hypothesis that bats use SRs in response to habitat destruction. The use of SRs increases with latitude in Europe, but not in North America, despite decreasing areas of human‐altered habitats. Historical processes related to the length of coexistence between bats and humans on both continents, rather than the current state of nature, may underlie the contrasting patterns observed. [ABSTRACT FROM AUTHOR]

The vertical distribution of tropospheric O3 from ozonesondes is compared with that from In-service Aircraft for a Global Observing System (IAGOS) measurements collected at 23 pairs of sites between about 30° S and 55° N from 1995 to 2021. Profiles of tropospheric O3 from IAGOS are generally in good agreement with ozonesonde observations from electrochemical concentration cells (ECCs), Brewer–Mast sondes, and carbon–iodine sensors, with average biases of 2.58, -0.28 , and 0.67 ppb and correlation coefficients (R) of 0.72, 0.82, and 0.66, respectively. Agreement between aircraft and Indian-sonde observations is poor, with an average bias of 15.32 ppb and an R value of 0.44. The O3 concentration observed by ECC sondes is, on average, 5 %–10 % higher than that observed by IAGOS, and the relative bias increases modestly with altitude. For other sonde types, there are some seasonal and altitudinal variations in the relative bias with respect to the IAGOS measurements, but these appear to be caused by local differences. The distance between the station and airport, when within 4° (latitude and longitude), has little effect on the comparison results. For the ECC ozonesondes, the overall bias with respect to the IAGOS measurements varies from 5.7 to 9.8 ppb when the station pairs are grouped by station–airport distances of <1° (latitude and longitude), 1–2°, and 2–4°. Correlations for these groups correspond to R=0.8 , 0.9, and 0.7. These comparison results provide important information for merging ozonesonde and IAGOS measurement datasets. They can also be used to evaluate the relative biases of different sonde types in the troposphere, using the aircraft as a transfer standard. [ABSTRACT FROM AUTHOR]

This study investigates global extreme precipitation events (EPEs) during warm seasons, with a particular focus on EPEs preceded by extreme heat stress (EPE-Hs) and a comparative analysis with those not (EPE-NHs). Using reanalysis product and Earth System Model data, the spatiotemporal characteristics and temperature sensitivities of EPEs are analyzed. Results show that EPE-Hs, while less frequent, have longer duration and greater magnitude compared to EPE-NHs, particularly in high latitude regions. In the future, a significant increase is projected in the characteristics of EPE-Hs, in contrast to the stable duration and magnitude of EPE-NHs. EPE-Hs demonstrate substantially higher temperature sensitivity than EPE-NHs, especially in low latitudes. The precipitation-temperature scaling relationships diverge markedly between EPE-Hs and EPE-NHs, with notable regional variations. These insights are pivotal for crafting region-specific early warning and adaptation strategies to mitigate the risks associated with extreme precipitation under the backdrop of global warming. [ABSTRACT FROM AUTHOR]

Reanalysis and satellite data indicate a decreasing precipitation area in recent decades, affecting local water resources and precipitation intensities. We have used CMIP6 simulations to test the hypothesis of a shrinking precipitation area in a warming climate. Our analyses reveal that SSP5-8.5 projections show a robust decrease in the precipitation area between 50 °S and 50 °N, and globally in 75% of the simulations. The new findings support the observed relationship, although to a lesser extent than earlier found in reanalysis and satellite data. We find a poleward shift of precipitation, increasing the daily precipitation area in the Arctic from 18% to 28%. At lower latitudes the precipitation area is reduced due to a decreasing occurrence of precipitation. These changes are related to the expansion of low relative humidity zones in the lower-to-mid troposphere, specifically at the poleward edges of the subtropics. [ABSTRACT FROM AUTHOR]

The projected winter changes of the North Atlantic eddy-driven jet (EDJ) under climate change conditions have been extensively analysed. Previous studies have reported a squeezed and elongated EDJ. However, other changes present large uncertainties, specifically those related to the intensity and latitude. Here, the projections of the EDJ in a multimodel ensemble of CMIP6 are scrutinised by using a multiparametric description of the EDJ. The multimodel mean projects non-stationary responses of the EDJ latitude through the winter, characterised by a poleward shift in early winter and equator migration in late winter. These intraseasonal shifts (rather than a genuine narrowing) explain the previously established squeezing of the EDJ and are linked to the future changes in different drivers: the 200 hPa meridional temperature gradient and Atlantic warming hole in early winter, and the stratospheric vortex in late winter. Model biases also influence EDJ projections, contributing to the poleward shift in early winter. [ABSTRACT FROM AUTHOR]

Africa, as one of the regions with significant political instability in the world today, experiences ongoing armed conflicts that have a serious impact on the peace and stability of the region and the international situation. Based on data from three types of armed conflict points in the 54 countries of Africa, a study was conducted on the spatiotemporal distribution patterns of armed conflicts in Africa from 1989 to 2021, using statistical analysis, kernel density, average center, and hotspot analysis methods. The results are as follows:(1)From 1989 to 2021, armed conflicts in Africa showed a trend of increase, decrease, and then increase again, exhibiting an overall "U-shaped" development pattern. At the same time, the number of conflicts is on the rise, with the hierarchy of conflict types being state armed conflicts > one-sided violent armed conflicts > non-state armed conflicts;(2)The spatial distribution characteristics revealed by kernel density analysis show that armed conflict outbreak points in Africa roughly form a "three" pat‐ tern from North Africa to South Africa. The main concentration of armed conflict outbreaks is along the Mediterranean coast, the region around 10° north and south latitude that crosses the equator, and the southern region of Africa;(3)The migration of armed conflict centers in Africa is mainly concentrated in the central region of Africa, intersected by the equator. The migration path of the centers includes the Democratic Republic of Congo, Chad, South Sudan, and the Cen‐ tral African Republic;(4)In terms of the distribution of hotspots and cold-spots, the high concen‐ tration of armed conflicts in Africa is mainly found in the central region, the northern part of North Africa, and the northern part of East Africa. The relatively low-conflict areas are mainly located in the western part of West Africa, the southern part of Central Africa, the southern part of East Africa, and South Africa. [ABSTRACT FROM AUTHOR]

The recent development of data-assimilating reanalyses of the global ocean and sea ice enables a better understanding of the polar region dynamics and provides gridded descriptions of sea ice variables without temporal and spatial gaps. Here, we study the spatiotemporal variability of the Arctic sea ice area and thickness using the Global ocean Reanalysis Ensemble Product (GREP) produced and disseminated by the Copernicus Marine Service (CMS). GREP is compared and validated against the state-of-the-art regional reanalyses PIOMAS and TOPAZ, as well as observational datasets of sea ice concentration and thickness for the period 1993–2020. Our analysis presents pan-Arctic metrics but also emphasizes the different responses of ice classes, the marginal ice zone (MIZ), and pack ice to climate changes. This aspect is of primary importance since the MIZ accounts for an increasing percentage of the summer sea ice as a consequence of the Arctic warming and sea ice extent retreat, among other processes. Our results show that GREP provides reliable estimates of present-day and recent-past Arctic sea ice states and that the seasonal to interannual variability and linear trends in the MIZ area are properly reproduced, with the ensemble spread often being as broad as the uncertainty of the observational dataset. The analysis is complemented by an assessment of the average MIZ latitude and its northward migration in recent years, a further indicator of the Arctic sea ice decline. There is substantial agreement between GREP and reference datasets in the summer. Overall, GREP is an adequate tool for gaining an improved understanding of the Arctic sea ice, also in light of the expected warming and the Arctic transition to ice-free summers. [ABSTRACT FROM AUTHOR]

This article presents an analytical model for calculating representative daily‐periodic cycles of net surface radiation on a slope with any angle α$$ \alpha $$ (0∘≤α≤90∘$$ {0}^{\circ}\le \alpha \le 9{0}^{\circ } $$) and orientation, at any latitude and elevation (up to 2500 m), and for all seasons. Starting from the basic equations for estimating the daytime direct and diffuse components of the incoming solar radiation at the Earth's surface under clear‐sky conditions, a Fourier series expansion is derived to get an overall daily‐periodic expression, that is, covering both daytime and nighttime, which does not require data from observations, differently from most models available in the literature. Among various possible applications, this formulation is preliminary to evaluating the radiation and energy budgets driving daily‐periodic wind systems on a simple slope, as reproduced by the model presented in Part 2. [ABSTRACT FROM AUTHOR]

To date, whether Bergmann's rule, initially developed for individual species or closely related taxa, can be applied to broader taxa remains elusive. Using global distribution data for birds, mammals, reptiles, and amphibians, both species- and assemblage-based, we examined the role of species richness and related climate variables in shaping body size patterns across the globe and the Northern Hemisphere only and whether the temperature–body size relationship had a phylogenetic signal. The results show that when species in all four classes were combined, body size increased with latitude but declined with temperature, consistent with Bergmann's rule. Each group showed somewhat unique patterns but was mostly consistent with Bergmann's rule. The body size–temperature relationships were not constrained by phylogenetic relatedness. Warmer places had both large and many small-bodied species, whereas cold places had proportionally more large species. The temperature-dependent variations in body size have important implications for macroecology under climate change. [ABSTRACT FROM AUTHOR]

This work continues our earlier studies of the interaction between a monopolar vortex and a sheared zonal flow in the framework of a 1.5-layer quasi-geostrophic model, based on numerical experiments with singular vortices. Earlier examination of flows with shears of fixed sign showed that the interaction depends strongly on the latitudinal distribution of the gradient of background potential vorticity b(y) (y being the latitude). The latitude y0 at which b(y) changes sign turns out to be of particular importance. In the vicinity of y0, under certain conditions, there arises the zonal-strip region, which attracts (repels) prograde (retrograde) vortices. This effect is examined here for the zonal flows in the form of individual jets as well as for the systems of alternating zonal jets; in all these cases, the background-flow velocity shear and the parameter b(y) can change sign depending on y. It is shown that the vortex drifts to the nearest latitude y0 on the prograde side of the zonal flow, and the meridional speed of the trapped vortex almost vanishes, but its zonal speed is directed westward and approaches the Rossby-wave drift velocity. [ABSTRACT FROM AUTHOR]

Models of migratory behavior predict trade‐offs between fitness costs and benefits with respect to migration distance. Shorter migration distances may confer a fitness benefit by facilitating earlier breeding, however this is rarely investigated. We tested this hypothesis using a large‐scale geolocation (GLS) dataset from 109 rhinoceros auklets (Cerorhinca monocerata), a differentially migrating seabird, that was tagged at 12 breeding colonies along the Pacific Coast of North America, spanning southern California to the eastern Aleutian Islands, Alaska. Using GLS‐based position estimates, we determined the geographic centroid of the pelagic areas occupied by birds in winter (1 January–28 February) and then calculated the distance between their wintering centroids and colony of origin. We then used GLS light‐intensity and salt‐water immersion (wet/dry) data to determine each individual's date of egg‐laying the following spring. Rhinoceros auklets were very widely distributed across the northeastern Pacific Ocean in winter. Among all individuals, the distance between winter centroids and breeding colonies ranged from < 100 to > 2500 km, being greater among individuals originating from colonies at higher latitudes. As predicted, migration distance and colony latitude were positively related to lay date: after accounting for colony‐level differences in phenology, individuals that migrated shorter distances tended to lay their eggs earlier, a pattern that emerged across all populations. Our study links the migration distance of rhinoceros auklets to a fitness‐related outcome, underscoring the selective pressure that migration exerts on subsequent breeding activity. [ABSTRACT FROM AUTHOR]

We examine the distribution, habitat association, morphometrics, meristics, and reproductive attributes of Amblyraja radiata over much of its Canadian range, Grand Banks to Arctic waters. It is distributed widely on the shelf and upper slope between 30 and 1288 m, reaching highest density in 100–400 m and occupying most available temperatures, between −1.0 and 8.8 °C, but concentrating in 1.6–3.5 °C. The maximum (and average) size decreases with increasing latitude in a continuum from 102 cm (55 cm) in the south, to 45 cm (20 cm) in the north. The proportion of mature fish increases with depth (40% at 0–50 m to 80% at 1150–1200 m) and temperature (35% at <0 °C to 55% at 5+ °C). The size at maturity decreases south to north; size at onset of maturity in males—43 (south) to 19 (north) cm, in females—49 to 23 cm; length at 50% maturity in males—74 to 44 cm, in females—66 to 40 cm. A. radiata maturity is also reflected in the rapid increase in the size of secondary sexual characteristics. Some meristics were consistent over the entire study area (spines near the spiracles and shoulders) while others varied with latitude (teeth rows, midline spines, spines near the eyes, % dorsal fins joined, spines between dorsal fins) or by fish length/maturity; the tail length/total length as a proportion of total length decreased during Stage 1 then increased at onset of maturity. [ABSTRACT FROM AUTHOR]

Simple Summary: Understanding the distribution of plants and animals is a major focus of ecologists and is of increasing importance as temperatures rise and the world's climate becomes more unpredictable. One large-scale pattern that has often been observed is for the number of species in a group of interest to be greater in the tropics than towards the poles. Species also tend to decline in number at higher elevations. We examined the distribution of mayfly species, insects commonly found in streams, at multiple sites throughout New Zealand to see whether the numbers and identities of species were related to latitude and altitude. We found that the number of mayfly species declined from north to south, i.e., towards higher latitudes, and less strongly as elevation increased. Furthermore, the species composition of communities became increasingly different with distance along the latitudinal gradient. Our findings suggest that the species gradient has historical origins, with the north of North Island and the South Island mountains likely to have been important regions of speciation 1.5–0.5 million years ago. The distribution of species in relation to latitude and altitude is of fundamental interest to ecologists and is expected to attain increasing importance as the Earth's climate continues to change. Species diversity is commonly greater at lower than higher latitudes on a global scale, and the similarity of communities frequently decreases with distance. Nevertheless, reasons for such patterns are not well understood. We investigated species richness and changes in community composition of mayflies (Ephemeroptera) over 13 degrees of latitude at 81 locations throughout New Zealand by light-trapping and the benthic sampling of streams. Mayflies were also sampled along an altitudinal gradient on a prominent inactive volcano in the east of North Island. Sampled streams were predominantly in the native forest, at a wide range of altitudes from sea level to c. 1000 m a. s. l. A total of 47 of the 59 described New Zealand mayflies were recorded during the study, along with five undescribed morphospecies. Species richness declined and the degree of dissimilarity (beta diversity) of mayfly communities increased significantly from north to south but less strongly with increasing altitude. Our results suggest that the southward decline in species richness has historical origins with the north of the country having acted as a major refuge and region of speciation during the Pleistocene. The increasing dissimilarity of the northern and southern communities may reflect an increasingly harsh climate, variable amounts of subsequent southward dispersal of northern species and, in the South Island, the presence of species which may have evolved in the newly uplifted mountains during the Miocene–Pliocene. [ABSTRACT FROM AUTHOR]

Crown profile has been the key indicator for assessing tree vigor and has many potential applications in forest growth modelling and forest management. Based on the measurement of the branches for a total of 156 Larix kaempferi individual trees from Liaoning province, Hubei province and Gansu provinces, we developed a nonlinear mixed effects outer-and inner-crown profile model, which included tree variables, climate variables, competition indices, and site quality. The effects of dominant tree height (Hdom), competition indices and climate variables on crown modelling were analyzed. The results showed that climate, competition and Hdom all had significant effects on the outer-and inner-crown profile. Among them, the ratio of DBH of the subject tree to the DBH of the largest individual tree in the stand (DDM) is the most significant competition index. The outer-crown radius increased with the increasing of DDM, and the inner-crown radius decreased with the increasing of DDM. Hdom also showed significant effect on outer-and inner-crown radius. Mean warmest month temperature (MWMT) were selected as the best climate variable to incorporate into the outer-crown profile model, and mean coldest month temperature (MCMT) for the inner-crown profile model. The regularity for the difference of outer-crown radius among three regions was Gansu > Liaoning > Hubei and Liaoning > Hubei for the inner-crown radius. Compared with base model, mean square error reduction (MSER) of the nonlinear mixed effect outer-crown profile model was 22.3% and the nonlinear mixed effect inner-crown profile model was 37.5% compared to the base model. The relative contributions of each variable to the outer-crown profile were DBH (40.05%), site quality (31.11%), CR (16.16%), competition (5.83%), HD (5.47%), and MWMT (1.38%), and the relative contributions to the inner-crown profile were MCMT (40.79%), DBH (32.32%), site quality (25.68%), and competition (1.21%). [ABSTRACT FROM AUTHOR]

Using the case study of a sterile-type chilling disaster during the head-flowering phase of rice, this study presents a novel approach to constructing vulnerability curves that can overcome data limitations while also taking into account crop growth mechanisms. Meteorological data during 1990-2010 was used to generate sterile-type chilling scenarios at county scale, estimated rice yield losses through combining one crop model (MCWLA) and machine learning (XGBoost) method, finally developed sterile-type chilling vulnerability curves for each main rice-planting zone in China and estimated long-term historical (1961-2010) yield loss caused by sterile-type chilling disasters. The results showed that: (1) Machine learning could effectively reproduce the estimation ability of crop model (RRMSE<6%, R²>0.93). (2) The sterile-type vulnerability decreased with decreasing latitude, and was weaker in growing seasons for late rice than that in early rice. (3) The historical yield loss was higher for single rice (1224kg-hm-1) than for double rice (early rice: 868kg-hm-1; late rice: 807kg-hm-1). [ABSTRACT FROM AUTHOR]

Simple Summary: This study aimed to determine the serum levels of vitamin D in captive pachyderms in Europe, and whether there were any seasonal differences. For some species, comparing the temperature and UVB irradiation of the current captive locations with the wild-ranging areas, the required conditions may be met in summer. In contrast, for other species, this might not be the case. Therefore, the animals may be unable to endogenously produce vitamin D, leading to calcium and phosphorus imbalances that were only reported in captive pachyderms. For some of the pachyderms, it is known that they can absorb cholecalciferol from the digestive tract, but this is not the case for all studied pachyderms. Tapirs had very low vitamin D levels, similar to horses. The higher vitamin D levels of elephants and rhinoceroses could indicate that they are capable of producing vitamin D or absorb more cholecalciferol from their diet. When comparing both rhinoceros and elephant species in this study, differences with regard to their capability in endogenous production of vitamin D were shown. Indian rhinoceroses seem capable of producing enough endogenous vitamin D year-round, while both elephant species and the black rhinoceros are not. This study aimed to detect seasonal and species differences in serum 25-hydroxy vitamin D (25(OH)D) concentrations during summer and winter months in captive pachyderms in Europe. Both elephant species had low 25(OH)D while African elephants did not show a seasonal variation. Asian elephants had significantly higher 25(OH)D compared to their African counterparts but also did not show a seasonal difference. Both rhinoceros species investigated had higher 25(OH)D compared to both elephant species; the Indian rhinoceros had high circulating levels year-round, while the black rhinoceroses showed significantly lower 25(OH)D in winter. Malayan tapirs have very low 25(OH)D, comparable to horses. The higher 25(OH)D of elephants and rhinoceroses could indicate that elephants and rhinoceroses are capable of producing vitamin D. This might indicate that the Indian rhinoceroses are capable of producing enough endogenous vitamin D year-round at latitudes around 52° N, while both elephant species and the black rhinoceros are not. This study also showed that it is likely that both elephant species and rhinoceros species are capable of absorbing cholecalciferol from the digestive tract, according to the existing literature, while tapirs may not. [ABSTRACT FROM AUTHOR]

Accurate and robust positioning has become increasingly essential for emerging applications and services. While GPS (global positioning system) is widely used for outdoor environments, indoor positioning remains a challenging task. This paper presents a novel architecture for indoor positioning, leveraging machine learning techniques and a divide-and-conquer strategy to achieve low error estimates. The proposed method achieves an MAE (mean absolute error) of approximately 1 m for latitude and longitude. Our approach provides a precise and practical solution for indoor positioning. Additionally, some insights on the best machine learning techniques for these tasks are also envisaged. [ABSTRACT FROM AUTHOR]

The response of NO emission at 5.3 μm in the thermosphere to the geomagnetic storm on 24 April 2023 is analyzed using TIMED/SABER observations and TIEGCM simulations. Both the observations and the simulations indicate a significant enhancement in NO emission during the storm. Observations show two peaks around 50°S/N in the altitude–latitude distribution of NO emission and its relative variation. Additionally, the peak emission and enhancement are stronger on the nightside compared with the dayside. The peak altitude in the Northern Hemisphere is approximately 2–10 km higher than in the Southern Hemisphere; meanwhile, the peak altitude on the dayside is approximately 2–8 km higher than that on the nightside. Simulations reveal three peaks around 50°S, the equator, and 65°N, with peak altitudes at higher latitudes being slightly lower than those observed. In general, the altitude–latitude distribution structure of the relative variation in simulated NO emission matches observations, with two peaks around 50°S/N. TIEGCM simulations suggest that the increase in NO density and temperature during a geomagnetic storm can lead to an increase in NO emission at most altitudes and latitudes. Furthermore, the significant enhancement around 50°S/N is mainly attributed to the changes in NO density. [ABSTRACT FROM AUTHOR]

The research deals with the study of geomorphological phenomena of the drainage basin area of Wadi al-Qelt located between latitudes E°31 '55 "59 and °31 '48 "27 north, and longitudes N °35 '12 "22 and °35 '32 "51 east, and is one of the valleys of the eastern slopes of: the mountains of Ram Allah and Jerusalem, located within the mountain range of central Palestine, and ends in the Jordan Valley in the east of Jericho at the Jordan River coupler, It aims to vary the influence of geomorphological factors in the formation of terrain features, as the geological structure, both rock and tectonic, had the largest role in the geomorphological formation of the region, where doloms and soluble limestone rocks are spread, which resulted in the presence of karst forms, and marlin rocks that can be carved and eroded, which resulted in the active decline of slopes and the intensification of the number of river ranks. The second part of the structure, represented by the tectonic factor, resulted in its impact on the Afro-Asian groove (collapse pit), the direction and intensity of the general slope and the resulting increase in the energy of the valleys on vertical sculpture, deepening and formation of gorges and others, while the second factor represented by the ancient and current climate has clearly appeared its effects in the parts of the drainage basin, where the effects of the current climate appeared by the extreme variation of rain amounts between the parts of the study area, and the impact of the ancient climate was manifested in the lower basin Which was greatly affected by the change in the levels of the ancestor of the Dead Sea, which were alternating those parts, the study followed the descriptive, historical, and analytical approach to describe the geographical reality and its characteristics, trace geological eras, and employ (GIS) technology. It concluded that the basin consists of a set of structural geomorphological phenomena, phenomena resulting from erosion and sedimentation, and phenomena associated with weathering processes, and the study recommended carrying out many geomorphological studies on the region and identifying what abounds in the geography of the Wadi basin Clumping is a morphodynamic, morphodynamic process. [ABSTRACT FROM AUTHOR]

Whereas the latitudinal diversity gradient has been shown for a diverse set of taxa, a related macroecological pattern, the latitudinal specialization gradient (LSG), remains controversial. A classical expectation is that species should present more specialized interactions towards the equator, however, recent studies have provided conflicting evidence for this hypothesis. Here, we tested the LSG in a set of bird–malarial parasite networks across South America. Our analyses comprise 9763 individual birds surveyed in 52 communities, within eight biomes and spanning a gradient of 4700 km. We measured network‐level specialization through indices that account for increasingly comprehensive information. Binary specialization considers the occurrence/absence of interactions between each host–parasite pair; quantitative specialization is also affected by the frequency of interactions between each host–parasite pair; and phylogenetic specialization takes into account the phylogeny and abundances of host species. We found that, while binary specialization increases towards the equator, quantitative specialization decreases. Thus, despite each parasite lineage infecting a more restricted set from the available host species in low latitudes, infections were more evenly distributed among host species, than in higher latitudes. Additionally, using a structural equation model, we show that both direct and indirect effects contribute to this unexpected relationship. Direct effects are weak, and network‐specialization was mostly explained by host species and parasite lineage richness, evidencing that changes in network specialization along latitude are in a large part explained by the latitudinal diversity gradient for birds and malarial‐parasites. In the light of the accumulated evidence over the past years, reinforced by our findings, we suggest that the classical latitudinal specialization hypothesis should be reevaluated, making room for a theoretical framework able to encompass the conflicting results. [ABSTRACT FROM AUTHOR]

Subseasonal variability of atmospheric circulation in mid-high latitudes is highly correlated to the upper-level jet streams, acting as a major contributor to the global or regional persistent climate anomalies. In this study, the features of subseasonal concurrent variations (SCVs) between East Asian Polar Front Jet (EAPJ) and Subtropical Jet (EASJ), and corresponding atmospheric circulation and temperature anomalies in China are investigated by using the observational data and NCEP/NCAR reanalysis datasets. Results show that the main variability modes of the winter upper-level wind fields on subseasonal time scales are characterized by the meridional shift in opposite directions and out-of-phase variations in the intensity of the EASJ and EAPJ. These concurrent variations between the two jets have a significant oscillation cycle with a period of 10–25 days. Accompanied by the location (intensity) SCV of the two jets, the mid-latitude circulation systems show significant zonal shifts (local intensity changes), resulting in alternations of the atmospheric circulation between zonal and meridional types. The typical meridional circulation is characterized by a strong East Asian trough and its upstream strong high-pressure ridges. Meanwhile, gradient force between Siberian high and the Aleutian low is anomalously strong. As a result, the SCVs between two jets can cause widespread and persistent low temperature anomalies over China, usually lasting more than three days. In the case of the location SCV of the two jets, the low temperature anomalies concentrate in northern China, particularly in north of 40°N. In the case of the intensity SCV of the two jets, the low temperature anomalies occur in most parts of China, notably in south of 40°N. These results are helpful to improve the prediction of atmospheric circulation and temperature anomalies in East Asia during winter. [ABSTRACT FROM AUTHOR]

Genetic adaptation of soybean phenological stages to high‐latitude long‐day environments is the major pre‐requisite for enhancing regional plant‐based protein production. Both E‐genes controlling flowering and growing environment determine timing of flowering and maturity, and E‐gene composition might differ between Chinese and European soybeans bearing the potential for improving adaptability. Therefore, 140 early maturity elite soybean cultivars of either Chinese or European origin were genotyped for the E1 to E4 flowering loci, and genotypes were tested across 17 European environments spanning a latitude range from 45 to 52°N in order to determine effects of various E‐allele combinations. Differences in E‐allele composition between Chinese and European cultivars were largest for the loci E1 and E3. Wild‐type alleles significantly delayed flowering, and effects of particular E‐alleles were depending on geographic latitude. Consequently, photoperiod‐insensitive E‐haplotypes carrying several non‐functional alleles proved to be suitable for cultivation in higher latitudes, whereas photoperiod‐sensitive late‐maturity E‐haplotypes are adapted to lower latitudes only. Thus, breeding for new E‐haplotypes through combining Chinese and European alleles could enhance the potential for further soybean adaptation to northern growing regions. [ABSTRACT FROM AUTHOR]

The proliferation of alien species that can suppress resident species via biotic interactions represents a growing concern worldwide. Yet, how above‐ and below‐ground communities simultaneously respond to plant invasion, particularly across large spatial scales, remains poorly explored. We hypothesized plant invasion has a greater impact on recipient above‐ and below‐ground communities at lower than higher latitudes given that biotic interactions play a more significant role in shaping communities in more favourable, lower latitude environments.To test this hypothesis, we conducted a comprehensive field survey of 124 sites spanning a 1700‐km latitudinal gradient in China, to explore the effects of invasion of Alternanthera philoxeroides, a globally widespread invasive plant, on plant, soil fungal and above‐ground arthropod communities.Invasion of A. philoxeroides had divergent effects on beta diversity (i.e. variation in taxa composition among sites) of plants, above‐ground arthropods and soil saprotrophic fungi, with negative, neutral and positive responses, respectively. Notably, the compositional dissimilarity of plant and arthropod communities between adjacent invaded and non‐invaded sites remained constant across latitudes. In contrast, the compositional dissimilarity of the entire and pathogenic fungal communities between adjacent invaded and non‐invaded sites increased with latitude. This resulted in a decreasing difference in invasion effects on the composition of plant and fungal communities with increasing latitude.Synthesis. Our study provides novel insights into the complexities of invasion effects by revealing contrasting responses of above‐ and below‐ground communities to plant invasion across latitudes. The contrasting responses could weaken or reshape above‐ and below‐ground interactions, and, in turn, affect future species invasions and the functioning of terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Introduction: The deficiency of Vitamin D is a widely unacknowledged and disregarded health issue globally. The prevalence of this condition is observed across all age groups and genders, affecting various systems in the body. Objectives: To assess the prevalence of hypovitaminosis D among the adult population and compare vitamin D levels between genders, age groups and geographical locations in patients visiting a secondary care hospital at Dimapur. Methods: A retrospective study was carried out over the period of one year from January 2022 to December 2022 on 665 patients (male: 33%, female: 64%) attending the outpatient and inpatient departments. Vitamin D levels were analyzed using enhanced chemiluminescence (vitros 5600). Results: Out of 665 patients, 90 (14%) were found to be vitamin D deficient, 281 (42%) insufficient, 289 (43%) sufficient and 5 (1%) had toxic levels. Males showed a higher percentage (64%) in the vitamin D deficiency and insufficiency groups as compared with females (46%). In the age group of 42-53 years, a higher percentage of people (57%) were found to be affected with vitamin D deficiency and insufficiency. In the regional distribution of vitamin D status, it is observed that the people in the hilly regions have a higher percentage (61%) of vitamin D deficiency and insufficiency as compared with the valley regions (50%). However, there is no statistical difference in mean vitamin D levels within the deficient, insufficient and sufficient groups between genders, different age groups and geographical regions. Conclusion: The present study carried out on patients from a secondary care hospital at Dimapur, Nagaland, shows that males have a higher percentage in vitamin D deficiency and insufficiency. In the age group of 42-53 years, a higher percentage of people were found to be affected with vitamin D deficiency and insufficiency. The vitamin D status of those living in the hilly region shows a higher percentage of vitamin D deficiency and insufficiency. However, there is no statistical difference in mean vitamin D levels within the deficient, insufficient and sufficient groups between genders, different age groups, and between hilly regions and valley regions [ABSTRACT FROM AUTHOR]

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The tropopause is an important transition layer and can be a diagnostic of upper-tropospheric and lower-stratospheric structures, exhibiting unique atmospheric thermal and dynamic characteristics. A comprehensive understanding of the evolution of fine tropopause structures is necessary and primary for the further study of complex multi-scale atmospheric physical–chemical coupling processes in the upper troposphere and lower stratosphere. A novel method utilizing the bi-Gaussian function is capable of identifying the characteristic parameters of vertical tropopause structures and providing information on double-tropopause (DT) structures. The new method improves the definition of the cold-point tropopause and detects one (or two) of the most significant local cold points by fitting the temperature profiles to the bi-Gaussian function, which defines the point(s) as the tropopause height(s). The bi-Gaussian function exhibits excellent potential for explicating the variation trends of temperature profiles. The results of the bi-Gaussian method and lapse rate tropopause, as defined by the World Meteorological Organization, are compared in detail for different cases. Results indicate that the bi-Gaussian method is able to more stably and obviously identify the spatial and temporal distribution characteristics of the thermal tropopauses, even in the presence of multiple temperature inversion layers at higher elevations. Moreover, 5 years of historical radiosonde data from China (from 2012 to 2016) revealed that the occurrence frequency and thickness of the DT, as well as the single-tropopause height and the first and second DT heights, displayed significant meridional monotonic variations. The occurrence frequency (thickness) of the DT increased from 1.07 % (1.96 km) to 47.19 % (5.42 km) in the latitude range of 16–50° N. The meridional gradients of tropopause height were relatively large in the latitude range of 30–40° N, essentially corresponding to the climatological locations of the subtropical jet and the Tibetan Plateau. [ABSTRACT FROM AUTHOR]