Search

The rapid uplift of the Qinghai–Tibet Plateau and its aridification has significantly affected the distribution and community structure of the plants in these regions. However, most of the studies have focussed on vascular plants, and it has been unclear whether bryophytes, which are haploid plants, had similar historical population dynamics to other vascular plants during the dramatic geological and climatic environment changes of the Quaternary. This study used Syntrichia caninervis Mitt as the research object and investigated its genetic variation, differentiation and population dynamic history in China. We genotyped 27 populations throughout the distributional range of S. caninervis using two chloroplast DNA regions and 19 nuclear microsatellite loci and supplemented these data with ecological niche modelling of the potential distribution areas from the last interglacial period. The results showed that genetic data consistently identified three clades: the Qinghai–Tibet Plateau, Pamir Plateau–TienShan and Central Asia. The genetic variation of Syntrichia caninervis mainly occurred within populations and in the populations within a specific region. However, there was a significant gene exchange between the different regions. S. caninervis may have expanded during the glacial period and shrank during the interglacial period. This study provides new evidence for the dynamic population history of drought-tolerant bryophytes in response to severe environmental changes during the Quaternary glacial and interglacial cycles.

Soil biocrusts, as the fundamental component of drylands, alter soil microbial and plant community compositions, thus profoundly affecting soil multifunctionality (SMF). Biocrust development regulates microbial composition and eco‐physiological effects, but there have been limited assessments regarding how biocrust development impacts SMF through microbial communities and plant species. We investigated the geographical patterns of plant diversity, soil bacterial diversity, biocrust development and SMF along an aridity gradient, spanning 2,200 km in northern China, and evaluated how biocrust development modulated multiple soil functions related to carbon, nitrogen and phosphorus cycles. Plant species richness and SMF decreased linearly with increasing aridity (1‐AI), but the relationship of soil bacterial diversity and biocrust development index (BSCDI) with aridity differed between arid region and semi‐arid region. Plant diversity and soil bacterial diversity increased linearly with BSCDI in arid regions, but decreased linearly with BSCDI in semi‐arid regions. Both plant species and soil bacterial diversity exerted positive effects on SMF in arid regions, but soil bacterial diversity, rather than plant species, did not explain any variation in SMF in semi‐arid regions. Most importantly, biocrust development exerted direct effects on SMF in arid regions, but only indirect effects through changing soil microbial biomass carbon in semi‐arid regions. Our findings suggest that the effects and influencing pathways of biocrusts on SMF are different between arid and semi‐arid regions, these results give a comprehensive view of how biocrust development facilitates soil multifunctionality improvement and ultimately promotes a deeper understanding of the dependence of biodiversity‐SMF relationship on aridity. A free Plain Language Summary can be found within the Supporting Information of this article.

Winter snowpack is an important source of moisture that influences the development of biological soil crusts (BSCs) in desert ecosystems. Cyanobacteria are important photosynthetic organisms in BSCs. However, the responses of the cyanobacterial community in BSCs to snowpack, snow depth and melting snow are still unknown. In this study, we investigated the cyanobacterial community composition and diversity in BSCs under different snow treatments (doubled snow, ambient snow and removed snow) and three snow stages (stage 1, snowpack; stage 2, melting snow; and stage 3, melted snow) in the Gurbantunggut Desert in China. In stages 1 and 2, Cyanobacteria were the dominant phylum in the bacterial community in the removed snow treatment, whereas Proteobacteria and Bacteroidetes were abundant in the bacterial communities in the ambient snow and doubled snow treatments. The relative abundances of Proteobacteria and Bacteroidetes increased with increasing snow depth. The relative abundances of Cyanobacteria and other bacterial taxa were affected mainly by soil temperature and irradiance. In stages 2 and 3, the relative abundance of Cyanobacteria increased quickly due to the suitable soil moisture and irradiance conditions. Oscillatoriales, Chroococcales, Nostocales, Synechococcales and unclassified Cyanobacteria were detected in all the snow treatments, and the most dominant taxa were Oscillatoriales and Chroococcales. Various cyanobacterial taxa showed different responses to snowpack. Soil moisture and irradiance were the two critical factors shaping the cyanobacterial community structure. The snowpack depth and duration altered the soil surface irradiance, soil moisture and other soil properties, which consequently were selected for different cyanobacterial communities. Thus, local microenvironmental filtering (niche selection) caused by snow conditions may be a dominant process driving shifts in the cyanobacterial community in BSCs.

Developing suitable photocatalysts is critical for CO2 photoreduction processes using solar energy. Here, three kinds of lanthanum bismuth oxide semiconductors (La0.225Bi0.775O1.5, La0.6Bi0.4O1.5, and La1.08Bi0.92O3.03) were found to exhibit activity for photocatalytic CO2 reduction without any sacrificial agent. These photocatalysts showed 98% selectivity for CO2 conversion to CO. Among these photocatalysts, La0.225Bi0.775O1.5 exhibited the best performance (33.2 μmol g−1) for CO2 photoreduction, which was approximately twice that of La0.6Bi0.4O1.5 and La1.08Bi0.92O3.03. La0.225Bi0.775O1.5 had a higher CO2 adsorption capacity and more negative conduction band position than the other two photocatalysts. Furthermore, time-resolved fluorescence decay spectroscopy showed that La0.225Bi0.775O1.5 had a much longer emission lifetime than La0.6Bi0.4O1.5 and La1.08Bi0.92O3.03, indicating the reduced recombination of photogenerated electrons and holes in La0.225Bi0.775O1.5. We proposed a lattice oxygen-mediated mechanism for CO2 photoreduction over La0.225Bi0.775O1.5 in this study.

Luminescent solar concentrators (LSCs) are large-area sunlight collectors coupled to small area solar cells, for efficient solar-to-electricity conversion. The three key points for the successful market penetration of LSCs are: (i) removal of light losses due to reabsorption during light collection; (ii) high light-to-electrical power conversion efficiency of the final device; (iii) long-term stability of the LSC structure related to the stability of both the matrix and the luminophores. Among various types of fluorophores, carbon quantum dots (C-dots) offer a wide absorption spectrum, high quantum yield, non-toxicity, environmental friendliness, low-cost, and eco-friendly synthetic methods. However, they are characterized by a relatively small Stokes shift, compared to inorganic quantum dots, which limits the highest external optical efficiency that can be obtained for a large-area single-layer LSC (>100 cm2) based on C-dots below 2%. Herein, we report highly efficient large-area LSCs (100–225 cm2) based on colloidal C-dots synthesized via a space-confined vacuum-heating approach. This one batch reaction could produce Gram-scale C-dots with a high quantum yield (QY) (∼65%) using eco-friendly citric acid and urea as precursors. Thanks to their very narrow size distribution, the C-dots produced via the space-confined vacuum-heating approach had a large Stokes shift of 0.53 eV, 50% larger than C-dots synthesized via a standard solvothermal reaction using the same precursors with a similar absorption range. The large-area LSC (15 × 15 × 0.5 cm3) prepared by using polyvinyl pyrrolidone (PVP) polymer as a matrix exhibited an external optical efficiency of 2.2% (under natural sun irradiation, 60 mW cm−2, uncharacterized spectrum). After coupling to silicon solar cells, the LSC exhibited a power conversion efficiency (PCE) of 1.13% under natural sunlight illumination (20 mW cm−2, uncharacterized spectrum). These unprecedented results were obtained by completely suppressing the reabsorption losses during light collection, as proved by optical spectroscopy. These findings demonstrate the possibility of obtaining eco-friendly, high-efficiency, large-area LSCs through scalable production techniques, paving the way to the lab-to-fab transition of this kind of devices.

Luminescent solar concentrators (LSCs) are large-area sunlight collectors, consisting of a waveguide embedded with fluorophores. LSCs could reduce the use of expensive silicon solar cells, thus decreasing the cost of electricity. Although great efforts have been made for fabricating high efficiency large-area LSCs, there is still a lack of knowledge of the temperature effect on the performance of the LSCs based on colloidal quantum dots (QDs) because the LSCs need to be operated in outdoor conditions. In this work, we investigated the thermal effect on the performance of the LSCs based on colloidal QDs upon sunlight irradiation under different temperatures (10–40 °C). The optical properties (e.g. quantum yield and optical efficiency) of the LSCs are strongly dependent on the operating temperature. With increasing operating temperature, the quantum yield and optical efficiency decrease significantly. Among three types of configuration, the LSC based on thin-film QDs coated on glass has the lowest temperature increase under operation, due to the higher thermal conductivity of the glass compared to the polymer matrix. Considering the real operating conditions of the LSCs, the glass-based LSCs have promising potential for future high-efficiency LSC-PV systems.

The strategic goals of the United Nations and the Aichi Targets for biodiversity conservation have not been met. Instead, biodiversity has continued to rapidly decrease, especially in developing countries. Setting a new global biodiversity framework requires clarifying future priorities and strategies to bridge challenges and provide representative solutions. Hyper-arid, arid, and semi-arid lands (herein, arid lands) form about one third of the Earth's terrestrial surface. Arid lands contain unique biological and cultural diversity, and biodiversity loss in arid lands can have a disproportionate impact on these ecosystems due to low redundancy and a high risk of trophic cascades. They contain unique biological and cultural diversity and host many endemic species, including wild relatives of key crop plants. Yet extensive agriculture, unsustainable use, and global climate change are causing an irrecoverable damage to arid lands, with far-reaching consequences to the species, ground-water resources, ecosystem productivity, and ultimately the communities' dependant on these systems. However, adequate research and effective policies to protect arid land biodiversity and sustainability are lacking because a large proportion of arid areas are in developing countries, and the unique diversity in these systems is frequently overlooked. Developing new priorities for global arid lands and mechanisms to prevent unsustainable development must become part of public discourse and form the basis for conservation efforts. The current situation demands the combined efforts of researchers, practitioners, policymakers, and local communities to adopt a socio-ecological approach for achieving sustainable development (SDGs) in arid lands. Applying these initiatives globally is imperative to conserve arid lands biodiversity and the critical ecological services they provide for future generations. This perspective provides a framework for conserving biodiversity in arid lands for all stakeholders that will have a tangible impact on sustainable development, nature, and human well-being.

The difficulty of effectively monitoring and managing the environment to conserve biodiversity is as yet an unsolved conundrum. A project of the Chinese Academy of Sciences has concluded that progress can be made through the use of flagship species selected using criteria drawn from conservation biology, ecosystem function, socio-economics, and cultural importance. Inclusion of the latter three criteria will help attract and maintain the commitment of the public to play full parts in carrying out any conservation measures needed. A system is proposed for scoring species to select those that are most suitable as flagships. This method can be used regardless of the size of the area chosen for attention, whether it is a region, a country, or a particular protected area., Highlights • Solve conservation problem. • Criteria to select flagship species. • Scoring system. • Governance of biodiversity.

Ramie fiber as the longest natural cellulose fiber in the world has been widely used in textile production. However, the rigidity of ramie fiber greatly restricts its application in high value-adde...

Design and synthesis of heterostructured carbon nanofibers is significant for applications in the field of optoelectronics, conductors and catalytic devices. Although lignin has been widely used as building blocks for fabricating nanofibers, it is still very challenging to synthesize conducting heterostructured carbon nanofibers without using additional catalysts. Herein, we first in-situ grew graphene grafted carbon nanofibers (G/CNFs) using calcium lignin sulfonate as starting materials without addition of catalysts. Through the electrospinning, pyrolysis and washing procedure, the as-spun nanofibers are converted into the flexible G/CNFs films. The in-situ formed CaS nanoparticles serve as catalysts for the growth of graphene on the surface of the CNFs, when the carbonization temperature is over 1100 °C. The as-prepared G/CNFs films exhibit superior electronic conductivity of 2377.9 S m−1, which is comparable to the values reported in the literature. As a proof-of-concept, the as-fabricated lithium-sulfur battery exhibits a high discharge of 808.7 mAh·g−1 after 600 cycles at 0.2 C by using the G/CNFs membrane as stand-alone and flexible sulfur cathode scaffolds. This work represents a promising new approach for designing heterostructured graphene/CNFs using low-cost lignin precursors, and provides significant insights for the sustainable development of CNFs in numerous applications.

The conversion of oasis-desert ecotones for agricultural use is a recent and ongoing trend. To evaluate the impacts of different land-use types and disturbance intensities (distance from farmland) on ecotonal vegetation, we investigated the plant community structure and growth of dominant species in an oasis-desert ecotone in the southern Taklimakan Desert. We established six 100 × 100 m plots, each associated with a particular land-use type in two respective locations: farmland margins and peripheral desert. Twelve and five species, respectively, were recorded at these two sites, with the latter containing fewer annual species. Species richness in the ecotone corresponded to the size of the investigated area. Plant coverage was generally two to eight times higher in the farmland margins than in peripheral desert areas. The species richness, plant coverage, and diversity indices at the two sites varied according to the land-use type. An increased distance from farmland corresponded to changes in the community structure for some land-use types, whereas in most instances, species richness differed by only one species within 100 m of farmland. Plant density and coverage were relatively higher in subplots located 0–20 m away from farmland than in other subplots, although these differences were nonsignificant. Whereas land-use types affected some of the growth indices of the dominant species Alhagi sparsifolia, we observed few significant distance effects. These results indicate that plant community structures and the growth of dominant species vary with landscape heterogeneity or land-use type. The distance effects are dependent on the land-use type. Over a short time period, irrigation is beneficial for the establishment of annual plants around farmland, but it is not beneficial for perennial plants that use ground water. However, further assessments of the long-term effects of agricultural activities on plant community structures, especially on dominant shrubs, are needed.

Studies of biological soil crusts (biocrusts) have proliferated over the last few decades. The biocrust literature has broadened, with more studies assessing and describing the function of a variety of biocrust communities in a broad range of biomes and habitats and across a large spectrum of disciplines, and also by the incorporation of biocrusts into global perspectives and biogeochemical models. As the number of biocrust researchers increases, along with the scope of soil communities defined as ‘biocrust’, it is worth asking whether we all share a clear, universal, and fully articulated definition of what constitutes a biocrust. In this review, we synthesize the literature with the views of new and experienced biocrust researchers, to provide a refined and fully elaborated definition of biocrusts. In doing so, we illustrate the ecological relevance and ecosystem services provided by them. We demonstrate that biocrusts are defined by four distinct elements: physical structure, functional characteristics, habitat, and taxonomic composition. We describe outgroups, which have some, but not all, of the characteristics necessary to be fully consistent with our definition and thus would not be considered biocrusts. We also summarize the wide variety of different types of communities that fall under our definition of biocrusts, in the process of highlighting their global distribution. Finally, we suggest the universal use of the Belnap, Büdel & Lange definition, with minor modifications: Biological soil crusts (biocrusts) result from an intimate association between soil particles and differing proportions of photoautotrophic (e.g. cyanobacteria, algae, lichens, bryophytes) and heterotrophic (e.g. bacteria, fungi, archaea) organisms, which live within, or immediately on top of, the uppermost millimetres of soil. Soil particles are aggregated through the presence and activity of these often extremotolerant biota that desiccate regularly, and the resultant living crust covers the surface of the ground as a coherent layer. With this detailed definition of biocrusts, illustrating their ecological functions and widespread distribution, we hope to stimulate interest in biocrust research and inform various stakeholders (e.g. land managers, land users) on their overall importance to ecosystem and Earth system functioning. This work was conducted as part of the “Completing the dryland puzzle: creating a predictive framework for biological soil crust function and response to climate change” Working Group supported by the John Wesley Powell Center for Analysis and Synthesis, funded by the U.S. Geological Survey. V.B.C. is funded by the National Science Foundation (DEB-1844531). F.T.M. acknowledges support from the European Research Council (ERC Grant Agreement 647038 [BIODESERT]) and Generalitat Valenciana (CIDEGENT/2018/041). K.E.Y. and A.D.-N. were supported by the National Science Foundation (#1557162 & #1557135). E.R.-C. was supported by the Ramon y Cajal fellowship (RYC2020-030762-I) and the REBIOARID Project (2018-101921-B-I00) founded by FEDER/Ministerio de Ciencia e Inovacion-Agencia estatal de investigacion, and the BIOCOST project (Conservación debiocostras como estrategia de adaptación al cambio climático: alineando avances científicos con la gestión y sociedad) supported by the Biodiversity Foundation of the Ministry for the Ecological Transition and the Demographic Challenge. S.C.R. was supported by USGS Ecosystems Mission Area. E.H.-S. acknowledges financial support from CONACYT grant SEP-CB-2015-01-251388.

Usually, it is subjective, laborious, and inefficient about the traditional water-based air-tightness test. In this article, a mechanism and method of leak detection for a pressure vessel is proposed. First, through collecting and analyzing sequential pressure data, the beginning time of the air-tightness test phase is determined. Second, pressure vessels are located using a deep convolutional neural network (DCNN)-based method and relocation strategy. Third, a method that employs a subregion voting strategy, background modeling, and sequential pressure data is proposed to determine whether, where, and how a pressure vessel leaks. An improved pressure vessel air-tightness test mechanism is developed to provide the basic support for leak detection framework and improve test efficiency. On the independent data set, the accuracy of the proposed leak location method is 98%, and the maximum error of the leakage calculation is 2.14 mL/min. Experiments show that the proposed leak detection framework and mechanism can greatly improve the efficiency and reliability of pressure vessel leak detection.

Seed germination profoundly impacts plant community composition within the plant life cycle. Snow is an important source of water for seed germination in the temperate deserts of Central Asia. Understanding how seed germination responds to variations in snow cover in relation to seed traits and plant ecological characteristics can help predict plant community sustainability and stability in Central Asia under a scenario climate change. This study investigated the seed germination of 35 plant species common to the Gurbantunggut Desert in Central Asia under the three snow treatments: (1) snow addition; (2) ambient snow; and (3) snow removal. Two-way analysis of variance (ANOVA) tests were performed to assess interactions among the impacts of snow treatments, seed traits and plant ecological characteristics on seed germination. Phylogenetic generalized least-squares (PGLS) model was used to test the relationships between seed traits and seed germination. The results demonstrated that snow variations had no significant impacts on seed germination overall. Seed germination under the snow addition treatment was similar with that under the ambient snow treatment, irrespective of seed traits and plant ecological characteristics. Snow removal only had negative impacts on seed germination for certain groups of seed traits and plant ecological characteristics. Seed mass positively affected seed germination, showing a linear increase of arcsin square root-transformed seed germination with log-transformed seed mass. Seed shape also profoundly impacted seed germination, with a higher germination percentage for elongated and flat seeds. Seed germination differed under different plant life forms, with semi-shrub species showing a significantly higher germination percentage. Most importantly, although snow treatments, seed traits and plant ecological characteristics had no interactive effects on seed germination overall, some negative impacts from the snow removal treatment were detected when seeds were categorized on the basis of seed mass and shape. This result suggests that variations of snow cover may change plant community composition in this temperate desert due to their impacts on seed germination.

The geographical region of Central Asia comprises Kazakhstan, Kyrgyzstan, Tajikistan, Uzbekistan, Turkmenistan, and the Xinjiang Uygur Autonomous Region of China. Central Asia’s temperate forests, steppes, and sandy deserts, including riparian tugai forests, have been identified by the World Wide Fund for Nature as Global 200 ecoregions, and the Mountains of Central Asia are considered biodiversity hotspots. Here, we describe and analyze the diverse characteristics and utilization of plant diversity and resources of the region. We confirm that there are 9520 species of higher plants, 20% of which are endemic species, belonging to 138 families and 1176 genera. The vegetation geography of Central Asia can be divided into 5 provinces and 33 districts, and more than 65% species have a Central Asian geographical distribution pattern. Plant resource utilization can be grouped into 5 categories and 31 subcategories, including food, medicine, industry, environmental protection, construction, and plant germplasm. In this review, we also discuss the principal threats to plant biodiversity in Central Asia posed by global climate change and offer recommendations for conservation strategies.

In this study, La(OH)3-modified magnetic sodium carboxymethyl cellulose (La-MC) was prepared as adsorbents for phosphate, which exhibited excellent adsorption performance up to 62.98 mg P/g and magnetic property for easy recovery. The recovered adsorbents after phosphate sorption were subsequently used for photocatalytic reduction of Cr(VI) and possessed good photocatalytic activity. This work provided an excellent reference for developing a new way of extending life cycle of adsorbents by combining phosphate adsorption with photocatalysis for sequential removal of pollutants from water in the future.

Tissue and organ failure or loss is a major problem for human health, and the construction of tissue engineering porous scaffold materials is a core step in the repair of damaged tissue and organs. Fibers from the lotus (Nelumbo nucifera) plant can be a source of superfine fibers. Such fibers have excellent biocompatibility, and they are easy to convert into nanofibers that could be applied for tissue engineering. Lotus fibers were carboxyl-modified with the TEMPO/NaClO/NaBr system, and lotus nanofibers were prepared. The effect of oxidation conditions on their morphologies and degrees of oxidation were investigated. The diameters of the lotus nanofibers were about 15 nm. Additionally, the degrees of oxidation of lotus nanofibers increased with an increase of oxidation time. Moreover, the oxidized sodium alginate membranes crosslinked with carboxymethyl chitosan degraded quickly, with the degradation rates increased by 82.1% or 100.0% during a 14-day period. By increasing the dosage of carboxymethyl chitosan, the pH values tend to rise. In comparison, the degradation rates of the lotus nanofibers/alginate porous membranes crosslinked with carboxymethyl chitosan exhibited better performance in terms of microstructure, porosity, water absorption, mechanical properties (0.36 MPa /7.7%), and in vitro degradation (59.2%).

Time series forecasting is emerging as one of the most important branches of big data analysis. However, traditional time series forecasting models can not effectively extract good enough sequence data features and often result in poor forecasting accuracy. In this paper, a novel time series forecasting model, named SeriesNet, which can fully learn features of time series data in different interval lengths. The SeriesNet consists of two networks. The LSTM network aims to learn holistic features and to reduce dimensionality of multi-conditional data, and the dilated causal convolution network aims to learn different time interval. This model can learn multi-range and multi-level features from time series data, and has higher predictive accuracy compared those models using fixed time intervals. Moreover, this model adopts residual learning and batch normalization to improve generalization. Experimental results show our model has higher forecasting accuracy and has greater stableness on several typical time series datasets.

In forest ecosystems, interactions between overstory trees and understory herbs play an important role in driving plant species diversity. However, reported links between overstory tree and understory herb species diversity have been inconsistent, due to variations in forest types and environmental conditions. Here, we measured species richness (SR) and diversity (Shannon-Wiener (H') and Simpson's (D) indices) of overstory trees and understory herbs in the protected Tianshan Wild Fruit Forest (TWFF), Northwest China, to explore their relationships along the latitudinal, longitudinal, elevational, and climatic (current climate and paleoclimate) gradients in 2018. We found that SR, and H' and D diversity indices of overstory trees and understory herbs exhibited a unimodal pattern with increasing latitude and elevation (P

Production of deuterated cellulose is important from both theoretical and practical perspectives. In this study, cellulose fibers of cotton and Tencel fibers with exchange-resistant deuterium incorporation were prepared by hydrogen–deuterium exchange treatment. The effect of the micro-structure of cellulose crystallinity index as well as the reaction conditions including catalyst, reaction time, and temperature on the exchange-resistant deuterium incorporation process are reported. The ability of deuterated cellulose fibers to resist protium-exchange during H2O washing was also explored. The results found that higher crystallinity index is beneficial to stabilize the deuteration of cellulose fibers. Furthermore, alkaline catalysts such as sodium hydroxide or potassium carbonate and higher exchange temperature as well as longer reaction time contribute significantly to the stabilization of deuterium incorporation in the deuterated cellulose fibers. These observations revealed that the hydrogen–deuterium exchange treatment is effective to obtain exchange-resistant deuterium incorporated cellulose fibers. In addition, cotton fibers with several deuteration levels were produced and could be considered for the study of deuterium effect on cellulose properties.

Shadow detection and removal is a classic research in the field of image processing. This work aims to address the problem of shadow detection and removal for licence plate. The shadow detection and removal method based on inherent properties of licence plate is presented in this study. First, an S–V-channel-property-based shadow detection algorithm is investigated to extract the background-shaded area of licence plate. Afterwards, a shadow edge location algorithm is proposed to detect the complete shadow edge. Then, the shadow is removed on H, S, and V channels with different strategies, respectively. Also, a filter-based median filtering algorithm is employed to remove the pseudo-edge. Finally, the proposed method is verified through comparing with other generic shadow detection and removal methods quantitatively and qualitatively.

Plant dye is a promising dyestuff to be used in textiles due to its unique environmental compatibility. However, currently there is no effective method for the identification of plant-dyed and chemical-dyed textiles. In this study, near-infrared (NIR) spectroscopy combined with three kinds of pattern recognition methods, namely soft independent modeling of class analogy (SIMCA), partial least squares (PLS) regression and principal component regression (PCR), were applied to identify cotton fabrics dyed with plant and chemical dyes. A total of 336 plant dye and chemical dye dyed cotton fabrics were prepared and the NIR spectra were collected; 267 samples were used as the calibration set, while the remaining 69 samples were used as the validation set. After pretreatment with the Savitzky–Golay first derivative, the calibration model was constructed. In the SIMCA model, the correct recognition rate values of the calibration and prediction sets were 100% and 98.55%, respectively. The PLS model showed that the number of principal components (PCs) and the correlation coefficient ( R2) were 8 and 0.9978, respectively, and the results of PCR were PC = 10, R2 = 0.9937. Both methods were satisfactory for the predicted results. The overall results indicated that NIR spectroscopy could be used for rapid and nondestructive identification of plant-dyed cotton fabrics and chemical-dyed cotton fabrics.

Objective A hybrid small-caliber artificial vascular graft based on bilayer porcine small intestinal submucosa (SIS) with curdlan and dipyridamole mixture film serving as the so-called sandwich filler was developed for biological performance evaluation. We evaluated the performance of the graft and filler. Methods SIS was coated with heparin by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. Curdlan acted as the carrier of dipyridamole. Three types of graft tubes (2 mm internal diameter and 20 mm in length) were manufactured: bilayer SIS with 10% curdlan + 10% dipyridamole mixture film (SCD), bilayer SIS with 10% curdlan film (SC), and monolayer SIS (S). The remodeling characteristics of the grafts were evaluated by implanting them as bypass in rabbit carotid arteries for 2 and 3 months. Each group contained 16 rabbits, and 16 nonsurgical rabbits served as the control group. Results Eight rabbits of each group, including the graft occluded group, were killed at 2 months and the others were killed at 3 months. Follow-up showed that all 8 grafts in SCD group were patent at 2 months. Six of 16 grafts in the SC group and 5 of 16 grafts in the S group were occluded at 2 months. One of 8 SCD grafts were occluded at 3 months and the patent showed a confluent endothelium without intimal hyperplasia. The neointima layer was composed of circumferentially aligned vascular smooth muscle cells. At 3 months, SC and S group grafts showed incomplete endothelialization and varying degrees of mural thrombus, accompanied by occlusion in the SC group (3 of 8) and S group (2 of 8). Conclusions The novel hybrid small caliber artificial vascular graft exhibited an improvement in revascularization resulting in high patency rate.

A cadmium tolerant strain Cupriavidus sp. H29 could be applied on simultaneous removal of nitrate, phosphorus and cadmium. Response surface methodology (RSM) experiments showed that optimal removal...

Chronic myeloid leukemia (CML) is a myeloproliferative disorder with clonal proliferation of all myeloid cell lines. The disease typically manifests in three phases: chronic course followed by an accelerated phase and finally a terminal blast crisis. A blast crisis is defined as the presence of > 20% blasts in the peripheral blood or bone marrow. The blasts could be characterized as either myeloid (60-80% of cases) resulting in acute myeloblastic leukemia or lymphoid (20-30% of cases) resulting in acute lymphoblastic leukemia. In rare instances, a blast crisis could present with biphenotypic expression for both myeloid and lymphoid blasts. In such cases, about 6-10% of the time, the course of the disease is more aggressive and renders a poorer prognosis especially if there is evidence of extramedullary involvement. We present a case of a 41-year-old woman with history of CML who presented with acute biphenotypic blast crisis with extramedullary involvement in the context of aggressive chemotherapy. Literature review reveals < 10 reported cases of CML with biphasic transformation and only three cases of CML with acute leukemia on presentation. Most cases described are in pediatric patients with varied presentations and none involving extramedullary sites. Mortality rates in such cases are near 100% despite aggressive chemotherapy.

Bacterial cellulose (BC) and silk fibroin (SF) double-network hydrogel with high mechanical strength and biocompatibility was synthesized by using BC as the novel polymer substrate to absorb aqueous SF solution as the modifier. Fundamental physical characterizations were carried out by scanning electron microscopy, energy dispersive spectrometry, fourier transform infrared spectrometry, X-ray diffraction and X-ray photoelectron spectroscopy. Thermogravimetric and differential thermal analysis was used to investigate the stability of the hydrogel. Strength and biocompatibility of the BC/SF hydrogel for cartilage tissue engineering were evaluated by tensile strength tester and cell culture experiments. Results reveal that the BC/SF double-network hydrogel was prepared successfully, and the hydrogel could be used as a cartilage repair material in clinical application.

Anthropogenic long-term nitrogen (N) deposition may dramatically impact biocrusts due to the overarching N limitation of soil biota in deserts. Even low levels of N may reach a critical loading threshold altering biocrust constituents and function. To identify the impact of chronic and continuous low levels of N deposition on biocrusts, we created a realistic gradient mirroring anthropogenic N addition rate (2:1 NH

Turing structures typically emerge in reaction-diffusion processes far from thermodynamic equilibrium, involving at least two chemicals with different diffusion coefficients (inhibitors and activators) in the classic Turing systems. Constructing a Turing structure in homogeneous solutions is a large challenge because of the similar diffusion coefficients of most small molecule weight species. In this work, we show that Turing structure with near zero strain semi-coherence interfaces is constructed in homogeneous solutions subject to the diffusion kinetics. Experimental results combined with molecular dynamics and numerical simulations confirm the Turing structure in the spinel ferrite films. Furthermore, using the hard-soft acid-base theory, the design of coordination binding can improve the diffusion motion of molecules in homogeneous solutions, increasing the library of Turing structure designs, which provides a greater potential to develop advanced materials.

Dryland ecosystems are often nitrogen-limited, and small nitrogen inputs may produce large responses to dryland ecological processes, such as gaseous nitrogen emission. The effect of increased anthropogenic nitrogen deposition on N

Herbaceous synusia is an important component of shrub community/ecosystem in the Junggar Desert and contributes a large proportion of net primary productivity in spring and early summer. Soil in the Junggar Desert is seriously deficient in nitrogen (N), but herbaceous plants possess high N concentration and N:P (phosphorous) ratio at the individual and interspecies levels; however, the community-level leaf stoichiometric characteristics of herbaceous synusia, spatial distribution patterns, and the driving factors at the regional scale remain unclear. In this study, 79 sampling plots were set up across the entire Junggar Desert. Foliar samples were collected by whole-plant harvesting method in each sampling plot, and the status of foliar carbon (C), N, and P concentrations, stoichiometric ratios, interrelationships, spatial patterns, and influencing factors were systematically analyzed. Results showed that the average contents of foliar C, N, and P in herbaceous synusia were 331.47, 25.85, and 1.54 mg g−1, respectively, and foliar C:N, C:P, and N:P were 13.76, 225.91, and 17.30, respectively. In contrast to most terrestrial ecosystems and global vegetation, herbaceous synusia was characterized by low C, C:N, and C:P and high N and N:P. Foliar C, N, and P were linearly and allometrically correlated with one another significantly. The foliar N–C, P–C, and N–P scaling exponents were 1.987, 1.770, and 1.122, respectively, thus the order of accumulation rates of foliar C, N, and P was N > P > C. Foliar C, N, C:N, and N:P presented significant differences among different soil habitats and shrub communities. Foliar stoichiometric traits showed obvious and different spatial heterogeneity at the regional scale. Multi-environmental factors jointly influenced foliar stoichiometric traits, and climate and geographical factors presented greater impact than soil. In conclusion, the foliar C:N:P stoichiometric traits might be the unique and inherent property of desert herbaceous species in this study area formed by long-term adaptation to the arid and barren environments in Central Asia, and this finding should be fully considered in regional ecological conservation and management.

Simple Summary The broad objective of our study was to evaluate the life history flexibility of the annual Erodium oxyrhinchum in relation to the predicted changes in precipitation in the cold desert due to climate change. We compared the effects of dry and wet springs and dry and wet autumns on growth and F2 seed dormancy of plants from spring- and autumn-germinated seeds of the cold desert annual E. oxyrhinchum from 2016–2020. Also, the future climate for the region was modeled. Our results found that given the flexibility in the life history of E. oxyrhinchum, it seems unlikely that future climate change will have much of an impact on the life history and dominant position of this species in the herbaceous plant community in the unpredictable-rainfall environment of the cold desert. Our study challenges the commonly-held perception that desert organisms may be negatively affected by climate change. Abstract Interannual seasonal variability in precipitation may strongly affect the life history and growth of desert annual plants. We compared the effects of dry and wet springs and dry and wet autumns on growth and F2 seed dormancy of plants from spring (SG)- and autumn (AG)-germinated seeds of the cold desert annual Erodium oxyrhinchum. Vegetative and reproductive growth and F2 seed dormancy and germination were monitored from September 2016 to November 2020 in the sandy Gurbantunggut Desert in NW China in Central Asia. Dry autumns decreased the density of AG plants, and dry springs decreased the density of SG plants and growth of SG and AG plants. In dry springs, SG plants were more sensitive to precipitation than AG plants, while in wet springs SG and AG plants had similar responses to precipitation. During growth in both dry and wet springs, most morphological characters of SG and AG plants initially increased rapidly in size/number and then plateaued or decreased, except for SG plants in dry springs. In dry springs, most morphological characters of AG plants were larger or more numerous than those of SG plants, and they were larger/more numerous for SG plants in wet than in dry springs. The percentage biomass allocated to reproduction in SG plants was slightly higher in a wet than in a dry spring. A much higher proportion of dormant seeds was produced by AG plants in a wet spring than in a dry spring. Projected changes in precipitation due to climate change in NW China are not likely to have much of an effect on the biology of this common desert annual plant.

Using tubular kapok fibers (KF) and sodium alginate (SA) as the natural building block, we put forward a novel oriented neurovascular network-like superhydrophobic aerogel with robust dry and wet compression resilience by directional freeze-drying and chemical vapor deposition. In the block, SA forms aligned channel structures providing space for rapid oil transmission, while KF serves as vascular-like capillaries acting as instant “tentacle” to capture the tiny oil droplets in water, facilitating fascinating oil capture efficiency for versatile oil/water separation, The aerogel after dry and wet compression (under a strain of 60%) can recover 96.0% and 97.3% its original, respectively, facilitating stable oil recovery (81.1–89.8%) by squeezing, high separation efficiency (99.04–99.64%) and permeation flux separating oil contaminants from water. A pump-supported experiment shows the aerogel efficiently collecting oil contaminants from the water’s surface and bottom by 11503–25611 L·m−2·h−1. Particularly, the aerogel as robust oil droplets captor facilely achieves isolation of 99.39–99.68% emulsified oils from oil/water emulsions by novel oil trapping mechanism which simply involves exerting kinetic energy on emulsified oils through repeated oscillation, potentially indicating a simple and efficient alternative to membrane-based oily wastewater remediation via filtration.

Colloidal carbon quantum dots (C-dots) have attracted a lot of attention because of their excellent optical properties for various types of applications. Due to the complicated structure of C-dots, the photoluminescence (PL) mechanism of C-dots is still unclear. In particular, it is still a big challenge to understand well the surface chemistry of C-dots. In this work, we used a vacuum-heating approach to produce high-quality C-dots. With different purification procedures, the surface chemistry of C-dots can be well-controlled. Removal of Ca2+ by Na2CO3 led to the disappearance of the absorption at 405 nm and a decrease of the quantum yield. In addition, the Na2CO3 treated C-dots exhibited an excitation-dependent PL behavior. These results confirmed that Ca2+ can interact with the surface functional group of CO of the C-dots, forming a stable structure surrounding the C-dot core, which contributed to a high quantum yield (QY) of 65%, excitation-independent PL behavior and absorption at 405 nm. Furthermore, the PL of the C-dots is strongly dependent on the pH, indicating that the Ca2+ capped C-dots could be used as pH indicators. Our finding provides clear evidence for the surface-chemistry dependent PL behavior of C-dots.