The Palaeognathae comprise the flightless ratites and the volant tinamous, and together with the Neognathae constitute the extant members of class Aves. It is commonly believed that Palaeognathae ...originated in Gondwana since most of the living species are found in the Southern Hemisphere 1–3. However, this hypothesis has been questioned because the fossil paleognaths are mostly from the Northern Hemisphere in their earliest time (Paleocene) and possessed many putative ancestral characters 4. Uncertainties regarding the origin and evolution of Palaeognathae stem from the difficulty in estimating their divergence times 1, 2 and their remarkable morphological convergence. Here, we recovered nuclear genome fragments from extinct elephant birds, which enabled us to reconstruct a reliable phylogenomic time tree for the Palaeognathae. Based on the tree, we identified homoplasies in morphological traits of paleognaths and reconstructed their morphology-based phylogeny including fossil species without molecular data. In contrast to the prevailing theories, the fossil paleognaths from the Northern Hemisphere were placed as the basal lineages. Combined with our stable divergence time estimates that enabled a valid argument regarding the correlation with geological events, we propose a new evolutionary scenario that contradicts the traditional view. The ancestral Palaeognathae were volant, as estimated from their molecular evolutionary rates, and originated during the Late Cretaceous in the Northern Hemisphere. They migrated to the Southern Hemisphere and speciated explosively around the Cretaceous-Paleogene boundary. They then extended their distribution to the Gondwana-derived landmasses, such as New Zealand and Madagascar, by overseas dispersal. Gigantism subsequently occurred independently on each landmass.
•Nuclear genome fragments from extinct elephant bird species were recovered•A stable phylogenomic time tree for the Palaeognathae was inferred•A Laurasian origin of Palaeognathae is supported by molecular and morphological data•Ancestral paleognaths had small body size (∼3.5–5 kg) and probably were volant
Yonezawa et al. recover nuclear genome fragments from extinct elephant birds and reconstruct a stable phylogenomic time tree for the Palaeognathae. Their tree based on morphological characters places the fossil paleognaths from the Northern Hemisphere as the basal lineages. This evidence suggests a Laurasian origin of Palaeognathae.
The giant rhinoceros beetles (Dynastini, Scarabaeidae, Coleoptera) are distributed in tropical and temperate regions in Asia, America and Africa. Recent molecular phylogenetic studies have revealed ...that the giant rhinoceros beetles can be divided into three clades representing Asia, America and Africa. Although a correlation between their evolution and the continental drift during the Pangean breakup was suggested, there is no accurate divergence time estimation among the three clades based on molecular data. Moreover, there is a long chronological gap between the timing of the Pangean breakup (Cretaceous: 110–148 Ma) and the emergence of the oldest fossil record (Oligocene: 33 Ma). In this study, we estimated their divergence times based on molecular data, using several combinations of fossil calibration sets, and obtained robust estimates. The inter-continental divergence events among the clades were estimated to have occurred about 99 Ma (Asian clade and others) and 78 Ma (American clade and African clade), both of which are after the Pangean breakup. These estimates suggest their inter-continental divergences occurred by overseas sweepstakes dispersal, rather than by vicariances of the population caused by the Pangean breakup.
The giant rhinoceros beetles (Dynastini, Scarabaeidae, Coleoptera) are distributed in tropical and temperate regions in Asia, America and Africa. Recent molecular phylogenetic studies have revealed ...that the giant rhinoceros beetles can be divided into three clades representing Asia, America and Africa. Although a correlation between their evolution and the continental drift during the Pangean breakup was suggested, there is no accurate divergence time estimation among the three clades based on molecular data. Moreover, there is a long chronological gap between the timing of the Pangean breakup (Cretaceous : 110-148 Ma) and the emergence of the oldest fossil record (Oligocene : 33 Ma). In this study, we estimated their divergence times based on molecular data, using several combinations of fossil calibration sets, and obtained robust estimates. The inter-continental divergence events among the clades were estimated to have occurred about 99 Ma (Asian clade and others) and 78 Ma (American clade and African clade), both of which are after the Pangean breakup. These estimates suggest their inter-continental divergences occurred by overseas sweepstakes dispersal, rather than by vicariances of the population caused by the Pangean breakup.
The adsorption behavior of benzoic acid onto a water-compatible hypercrosslinked polymeric adsorbent NJ-8 was compared with that onto macroporous Amberlite XAD-4.This paper focuses on the static ...equilibrium adsorption behaviors,the adsorption thermodynamics and the column dynamic adsorption profiles.Five isotherm models are used to fit the results.This shows that the Freundlich equation can give a perfect fit.The specific surface area of NJ-8 is about as high as that of Amberlite XAD-4,but the adsorbing capacity for benzoic acid on NJ-8 is about 14.9%-64.8% higher than that on Amberlite XAD-4,which is attributed to its microporous mechanism and partial polarity.The negative values of the adsorption enthalpy are indicative of an exothermic process.Both enthalpy and free energy changes of adsorption manifest a physical sorption process.The negative values of the adsorption entropy indicate that adsorption is well consistent with the restricted mobilities and the configurations of the adsorbed molecules on the surface of the studied adsorbents with superficial heterogeneity.Both adsorbents were used in mini-column experiments to demonstrate the higher breakthrough adsorbing capacity of the hypercrosslinked polymeric adsorbent NJ-8 to benzoic acid,as compared with that of Amberlite XAD-4.
Scalable and economical methods for the production of optically pure amino acids, both natural and unnatural, are essential for their use as synthetic building blocks. Currently, enzymatic dynamic ...kinetic resolution (DKR) underpins some of the most effective processes. Here we report the development of enantioselective extraction coupled with racemization (EECR) for the chirality conversion of underivatized amino acids. In this process, the catalytic racemization of amino acids in a basic aqueous solution is coupled with the selective extraction of one enantiomer into an organic layer. Back-extraction from the organic layer to an acidic aqueous solution then completes the deracemization of the amino acid. The automation of the EECR process in a recycling flow reactor is also demonstrated. Continuous EECR is made possible by the sterically hindered chiral ketone extractant 5, which prevents the coextraction of the copper racemization catalyst because of its nonplanar geometry. Furthermore, the extractant 5 unexpectedly forms imines with amino acids faster and with greater enantioselectivity than less bulky derivatives, even though 5 cannot participate in intramolecular resonance-assisted hydrogen bonding. These features may allow EECR to challenge the preponderance of enzymatic DKR in the production of enantiomerically enriched amino acids.
We demonstrate an ultrasensitive wearable temperature sensor prepared using an emerging material, graphene nanowalls (GNWs), and its ease of combination with polydimethylsiloxane (PDMS). Fabrication ...of the sensor allows for a polymer-assisted transfer method making it considerably facile, biocompatible and cost effective. The resultant device exhibits a positive temperature coefficient of resistivity (TCR) as high as 0.214 °C −1 , which is three fold higher than that of conventional counterparts. We attribute this to the excellent stretchability and thermal sensitivity of GNWs together with the large expansion coefficient of PDMS. Moreover, the sensor is capable of monitoring body temperature in real time, and it presents a quite fast response/recovery speed as well as long term stability. Such wearable temperature sensors could constitute a significant step towards integration with the next frontier in personalized healthcare and human–machine interface systems.
The deterioration of soil and water resources resulting from tropical rainforest (TR) conversion to monoculture plantations (e.g., rubber monoculture; RM) could be restrained and restored through ...intercropping. However, the response of soil properties and forest water conservation function to forest conversion, i.e., the conversion of RM to rubber rainforest (RR: derived from the invasion of wild native plants in abandoned RM), is still unclear. We involved four forests types, TR, RM, rubber-tea agroforestry (RTA), and RR, as transitional steps of forest conversion through a space-for-time substitution approach to examine the dynamic of soil physical, hydrological and chemical properties during the forest conversion (from TR to RM, RM to RTA, RTA to RR, and retransformation into TR). The results show that SOC, TN, TP, and TK decreased in the order of TR > RR > RTA > RM, which was followed by the trend of soil hydrological and physical properties among these forest types. The interrelation between soil physical and chemical properties was mediated by water flow behaviours. High macroporosity and related low Ks in TR favoured the occurrence of water flow behaviours. Water flow behaviours not only influenced the distribution of soil chemical elements but also played a crucial role in forming appropriate conditions for nutrient turnover. The co-occurrence of preferential and matrix flow was more prevalent in the rainy season than dry season due to the higher frequency and higher amount of rainwater. The preferential flow promoted the soil water flow in the water flow paths and enhanced water storage in the soil pores. In short, the soil properties and soil water supply decreased in the following order: TR > RR > RTA > RM, suggesting that the severe soil degradation that occurred after TR conversion to RM can be restored back to the extent of TR after a period of succession. The results provided new insights for understanding the forest water conservation function and soil properties in response to forest conversion and highlighted that the RR appeared as a transitional stage during the course of forest restoration from RM to TR under low rubber demand. These findings improve the current knowledge of the relationship among soil physical, hydrological and chemical properties in the rubber-growing humid tropical region of Southeast Asia.
Zinc‐ion batteries are under current research focus because of their uniqueness in low cost and high safety. However, it is still desirable to improve the rate performance by improving the Zn2+ ...(de)intercalation kinetics and long‐cycle stability by eliminating the dendrite formation problem. Herein, the first paradigm of a high‐rate and ultrastable flexible quasi‐solid‐state zinc‐ion battery is constructed from a novel 2D ultrathin layered zinc orthovanadate array cathode, a Zn array anode supported by a conductive porous graphene foam, and a gel electrolyte. The nanoarray structure for both electrodes assures the high rate capability and alleviates the dendrite growth. The flexible Zn‐ion battery has a depth of discharge of ≈100% for the cathode and 66% for the anode, and delivers an impressive high‐rate of 50 C (discharge in 60 s), long‐term durability of 2000 cycles at 20 C, and unprecedented energy density ≈115 Wh kg−1, together with a peak power density ≈5.1 kW kg−1 (calculation includes masses of cathode, anode, and current collectors). First principles calculations and quantitative kinetics analysis show that the high‐rate and stable properties are correlated with the 2D fast ion‐migration pathways and the introduced intercalation pseudocapacitance.
New electrodes of Zn‐ion batteries. Strategies of novel layered mesoporous zinc orthovanadate, a Zn nanoarray, and a solid‐state electrolyte (SSE) are used to alleviate the dendrite growth problem. Intercalation pseudocapacitance in the cathode improves the rate capability. High energy and power densities are achieved with a depth of discharge of 100% for the cathode and 66% for the zinc anode.
Studies have shown that
and its extracts are effective herbal treatments for leukemia. We previously found that a polysaccharide from
, SFP 2205, stimulated apoptosis in human erythroleukemia (HEL) ...cells. However, the structural characterization and antitumoral mechanisms of SFP 2205 remain uncertain. Here, we studied the structural characteristics and anticancer mechanisms of SFP 2205 in HEL cells and a xenograft mouse model. The results demonstrated that SFP 2205, with a molecular weight of 41.85 kDa, consists of mannose, rhamnose, galactose, xylose, glucose, and fucose with monosaccharides composition of 14.2%, 9.4%, 11.8%, 13.7%, 11.0%, and 38.3%, respectively. On animal assays, SFP 2205 significantly inhibited growth of HEL tumor xenografts with no discernible toxicity to normal tissues. Western blotting showed that SFP 2205 therapy improved Bad, Caspase-9, and Caspase-3 protein expression, and ultimately induced HEL tumor apoptosis, indicating mitochondrial pathway involvement. Furthermore, SFP 2205 blocked the PI3K/AKT signaling pathway and 740 Y-P, an activator of the PI3K/AKT pathway, rescued the effects of SFP 2205 on HEL cell proliferation and apoptosis. Overall, SFP 2205 may be a potential functional food additive or adjuvant for preventing or treating leukemia.
Since the concept of four-dimensional (4D) printing first emerged from additive manufacturing technologies in 2013, there has been growing interest from researchers worldwide to harness its benefits ...for advanced manufacturing and materials design. 4D printing has the potential to extend the processing of objects beyond complex geometries by giving dynamic properties to static printed structures, which can change over time. The shapes and/or properties of printed objects can change under various stimuli, including heat, light, pH, moisture, electricity, and magnetic field, and these changes can be pre-designed and well-controlled. 4D printing thus permits the creation of variable and controllable geometries by incorporating the time dimension. In recent years, the rapid technical developments in smart materials and new printing methods have greatly expanded the scope of 4D printing. This article reviews important 4D printing technologies in conjunction with the underlying polymer science and engineering. The challenges and future opportunities in 4D printing are also discussed.
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