Study on the spatiotemporal distribution of algal blooms and its influencing factors in young reservoirs based on remote sensing interpretation.

Algal blooms caused by excessive proliferation of phytoplankton in young reservoirs have been frequently reported, seriously threatening the unstable aquatic ecosystem, water quality safety and public health. Thus, there is an urgent need to investigate the dynamics of phytoplankton in these young reservoirs, and many current studies on phytoplankton in young reservoirs are based on point monitoring information. This study used remote sensing interpretation to invert the chlorophyll-a concentration in 131 images of Zipingpu Reservoir from 2013 to 2021, and analyzed the spatiotemporal characteristics of algal blooms. Partial least squares-structural equation modeling was used to identify the environmental influencing factors of algal blooms. The results showed that the average chlorophyll-a concentration in the reservoir was 4.49 mg/m3, and the frequency of algal blooms was 28%. The maximum area of algal blooms shows a significant increase trend in the interannual (increase by 0.05%/yr in the proportion of water surface area), and the average blooms area shows a weaker increase trend (0.01%/yr). The prone period of algal bloom is from April to August every year. The solar duration and wind speed had significant direct positive effects on the maximum and average algal bloom area, which was the similar effects in different years and months (path coefficient exceeds 0.44). TP also has a significant direct positive effect on the average algal bloom area between different years (path coefficient of 0.30). The suitable meteorological factors level making the bloom-prone period from April to August, the prevailing westerly and southerly winds provide transport for the aggregation of phytoplankton and algal blooms outbreak in the northeastern waters. This study expand the monitoring frequency and spatial information of algal blooms, which provided a reference for young reservoir management and prevention of blooms.

Evidence for d-wave superconductivity of infinite-layer nickelates from low-energy electrodynamics.

The discovery of superconductivity in infinite-layer nickelates established another category of unconventional superconductors that shares structural and electronic similarities with cuprates. However, key issues of the superconducting pairing symmetry, gap amplitude and superconducting fluctuations are yet to be addressed. Here we utilize static and ultrafast terahertz spectroscopy to address these. We demonstrate that the equilibrium terahertz conductivity and non-equilibrium terahertz responses of an optimally Sr-doped nickelate film (superconducting transition temperature of Tc = 17 K) are in line with the electrodynamics of d-wave superconductivity in the dirty limit. The gap-to-Tc ratio (2Δ/kBTc) is found to be 3.4, indicating that the superconductivity falls in the weak coupling regime. In addition, we observed substantial superconducting fluctuations near Tc that do not extend into the deep normal state as the optimally hole-doped cuprates do. Our results support a d-wave system that closely resembles the electron-doped cuprates.

Geographic distribution and impacts of climate change on the suitable habitats of Glycyrrhiza species in China.

Climate change has a major impact on the growth and distribution of plants. Glycyrrhiza is widely used in the treatment of many diseases in China. However, with the overexploitation and the growing demand for medicinal uses in of Glycyrrhiza plants. The investigation of the geographical distribution of Glycyrrhiza plants and the analysis of future climate change are of great significance for the conservation of Glycyrrhiza. In this study, combined with administrative maps of Chinese provinces, the present and future of geographical distribution and richness of six Glycyrrhiza plants in China were studied by using DIVA-GIS and MaxEnt software. A total of 981 herbarium records of these six species of Glycyrrhiza were collected to research. Results show that the change of climate in the future will lead to an increase in habitat suitability for some Glycyrrhiza species as follows: Glycyrrhiza inflata by 61.6%, Glycyrrhiza squamulosa by 47.5%, Glycyrrhiza pallidiflora by 34.0%, Glycyrrhiza yunnanensis by 49.0%, Glycyrrhiza glabra by 51.7%, and Glycyrrhiza aspera by 65.9%. Glycyrrhiza plants have considerable medicinal and economic value, so it is necessary to adopt targeted development and rational management strategies for it.

Effects of climate change on the geographical distribution and potential distribution areas of 35 Millettia Species in China.

Climate change has an extremely important impact on the geographic distribution of plants. The genus Millettia is an important plant resource in China and is widely used in medicine and ornamental industries. Due to the continuous changes of climate and the development and utilization of plant resources of the genus Millettia, it is of great significance to systematically investigate the geographic distribution of plants of the Millettia and their potential distribution under climate change. DIVA-GIS software was used to analyze 3492 plant specimens of 35 species of genus Millettia in the herbarium, and the ecological geographic distribution and richness of Millettia were analyzed, and the MaxEnt model was used to analyze the current and potential distribution in the future. The results show that the genus Millettia is distributed in 30 provinces in China, among which Yunnan and Guangdong provinces are the most distributed. Our model determines that precipitation in the driest month and annual temperature range are the most important bioclimatic variables. Future climate changes will increase the suitable habitat area of M. congestiflora by 16.75%, but other cliff beans Suitable habitats for vines will decrease significantly: M. cinereal by 47.66%, M. oosperma by 39.16%, M. pulchra by 36.04%, M. oraria by - 29.32%, M. nitida by 22.88%, M. dielsiana by 22.72%, M. sericosema by 19.53%, M. championii by 7.77%, M. pachycarpa by 7.72%, M. speciose by 2.05%, M. reticulata by 1.32%. Therefore, targeted measures should be taken to protect and develop these precious plant resources.

Differentiated roles of Lifshitz transition on thermodynamics and superconductivity in La2-xSrxCuO4.

The effect of Lifshitz transition on thermodynamics and superconductivity in hole-doped cuprates has been heavily debated but remains an open question. In particular, an observed peak of electronic specific heat is proposed to originate from fluctuations of a putative quantum critical point p* (e.g., the termination of pseudogap at zero temperature), which is close to but distinguishable from the Lifshitz transition in overdoped La-based cuprates where the Fermi surface transforms from hole-like to electron-like. Here we report an in situ angle-resolved photoemission spectroscopy study of three-dimensional Fermi surfaces in La2-xSrxCuO4 thin films (x = 0.06 to 0.35). With accurate kz dispersion quantification, the said Lifshitz transition is determined to happen within a finite range around x = 0.21. Normal state electronic specific heat, calculated from spectroscopy-derived band parameters, reveals a doping-dependent profile with a maximum at x = 0.21 that agrees with previous thermodynamic microcalorimetry measurements. The account of the specific heat maximum by underlying band structures excludes the need for additionally dominant contribution from the quantum fluctuations at p*. A d-wave superconducting gap smoothly across the Lifshitz transition demonstrates the insensitivity of superconductivity to the dramatic density of states enhancement.

Anti-inflammatory Study on the Constituents of Angelica sinensis (Oliv.) Diels, Angelica dahurica (Hoffm.) Benth. & Hook.f. ex Franch. & Sav., Angelica pubescence Maxim and Foeniculum vulgare Mill. Essential Oils.

Umbelliferae plants, which are widely used as traditional Chinese medicine because of their characteristics of relieving rheumatism, alleviating fever, circulating blood and easing pain. This experimental study was based on ear edema model caused by 12-O-tetracycline-propylphenol-13-acetic acid (TPA) in mice and compared with the Ibuprofen (Ib) group. Gas chromatography-mass spectrometry (GC-MS) was used to analyse the composition of the essential oils from the four studied Umbelliferae plants (Angelica sinensis (Oliv.) Diels, A. dahurica (Hoffm.) Benth. & Hook.f. ex Franch. & Sav., A. pubescens Maxim and Foeniculum vulgare Mill.). Biologically active components in volatile oils from the four studied Umbelliferae plants were evaluated. The expression levels of inflammatory cytokines Tumor Necrosis Factor-α (TNF-α), Cyclooxygenase-2 (COX-2), Interleukin-6 (IL-6) and RelA (p65) in mouse skin were determined by immunohistochemical method. The refractive index of the four essential oils was calculated. A total of 239 compounds were identified by GC-MS from the four studied plants, and the main constituents were osthole (44.61%, APEOs), obepin (0.59%, APEOs & 86.58%, FVEOs), undecanol (8.58%, ADEOs), α-muurolene (7.95%, ADEOs) and cis-anethol (9.11%, ADEOs). E-ligustilide (0.14%, APEOs & 81.14%, ASEOs), (-)-spathulenol (0.08%, FVEOs & 1.21%, ASEOs), (-)-terpinen-4-ol (4.91%, FVEOs), 2-butylthiolane (5.76%, APEOs) and α-bisabolol (3.80%, APEOs). This study showed that all the essential oils from the four studied Umbelliferae plants contained various lactones, including ligustrongolactone, trans-anisol and imperatorin. According to the results of the TPA induction test in the mouse ear edema model, the essential oils of four Umbelliferae plants reduced the levels of inflammatory cytokines TNF-α, COX-2, IL-6 and p65. All of them showed extraordinary biological activity in anti-inflammatory, so they have potential application value for biomedical products, pharmaceutical preparations, natural functional nutrients and cosmetic additives.

Mechanism and Application of Surface-Charged Ferrite Nanozyme-Based Biosensor toward Colorimetric Detection of l-Cysteine.

Peroxidase-like nanozymes with robust catalytic capacity and detection specificity have been proposed as substitutes to natural peroxidases in biochemical sensing. However, the catalytic activity enhancement, detection mechanism, and application of nanozyme-based biosensors toward l-cysteine (l-Cys) detection still remain significant challenges. In this work, a doped ferrite nanozyme with well-defined structure and surface charges is fabricated by a two-step method of continuous flow coprecipitation and high-temperature annealing. The resulted ferrite nanozyme possesses an average size of 54.5 nm and a zeta-potential of 6.45 mV. A high-performance biosensor is manufactured based on the peroxidase-like catalytic feature of the doped ferrite. The ferrite nanozyme can oxidize the 3,3',5,5'-tetramethylbenzidine (TMB) with the assistance of H2O2 because of the instinctive capacity to decompose H2O2 into ·OH. The Michaelis-Menten constants (0.0911 mM for TMB, 0.140 mM for H2O2) of the ferrite nanozyme are significantly smaller than those of horseradish peroxidase. A reliable colorimetric method is established to selectively analyze l-Cys via a facile mixing-and-detecting methodology. The detection limit and linear range are 0.119 µM and 0.2-20 µM, respectively. Taking the merits of the ferrite nanozyme-based biosensors, the l-Cys level in the human serum can be qualitatively detected. It can be anticipated that the surface-charged ferrite nanozyme shows great application prospects in the fields of bioanalytical chemistry and point-of-care testing.

Variation in Compositions and Biological Activities of Essential Oils from Four Citrus Species: Citrus limon, Citrus sinensis, Citrus paradisi, and Citrus reticulata.

Species of the genus Citrus are cultivated in many regions of China and are widely used for medicinal purposes. In the present study, essential oils (EOs) were extracted from four different Citrus species using steam distillation. The chemical components of these four essential oils were separated using gas chromatography-mass spectrometry, and 52 compounds were confirmed. D-limonene was found to be the most abundant compound. All four essential oils demonstrated varied but remarkable radical scavenging capacity (IC50 ; 0.77-13.9 %). Citrus paradisi essential oil exhibited excellent antioxidant activity. Compared to ibuprofen, topical application of the four Citrus spp. essential oils significantly inhibited ear edema formation in mice. Furthermore, essential oils from the four Citrus species reduced the expression levels of interleukin-6 (IL-6), cyclooxygenase-2 (COX-2) and nuclear transcription factor kappa B p65 (NF-κB) to different degrees. The cytotoxicity of the four essential oils on BV2 microglial cells was determined using the MTT assay (IC50 ; 321.37-1558.87 µg/mL), wherein Citrus limon essential oil showed the lowest cytotoxicity. The essential oils of Citrus limon, Citrus reticulata, and Citrus paradisi had an inhibitory effect on the lung cancer cell lines H1299 by inducing a G0/G1 cell cycle arrest. Cluster and principal component analyses were used to determine the relationship among the Citrus species. These results suggest that the four Citrus essential oils have potential for use as active ingredients in functional foods or cosmeceutical products.

Prevention of IL-6 signaling ameliorates toluene diisocyanate-induced steroid-resistant asthma.

BACKGROUND: Accumulating evidence indicated the crucial role for interleukin 6 (IL-6) signaling in the development of allergic asthma. Yet, the role of IL-6 signaling in toluene diisocyanate (TDI)-induced mixed granulocytic airway inflammation still remains unclear. Thus, the aims of this study were to dissect the role of IL-6 signaling and to evaluate the effect of tocilizumab on TDI-induced steroid-resistant asthma. METHODS: TDI-induced asthma model was prepared and asthmatic mice were respectively given IL-6 monoclonal antibody, IL-6R monoclonal antibody (tocilizumab, 5 mg/kg, i.p. after each challenge) for therapeutic purposes or isotype IgG as control. RESULTS: TDI exposure just elevated IL-6R expression in the infiltrated inflammatory cells around the airway, but increased glycoprotein 130 expression in the whole lung, especially in bronchial epithelium. Moreover, TDI inhalation increased airway hyperresponsiveness (AHR) to methacholine, coupled with mixed granulocytic inflammation, exaggerated epithelial denudation, airway smooth muscle thickening, goblet cell metaplasia, extensive submucosal collagen deposition, dysregulated Th2/Th17 responses, as well as innate immune responses and raised serum IgE. And almost all these responses except for raised serum IgE were markedly ameliorated by the administration of IL-6 neutralizing antibody or tocilizumab, but exhibited poor response to systemic steroid treatment. Also, TDI challenge induced nucleocytoplasm translocation of HMGB1 and promoted its release in the BALF, as well as elevated lung level of STAT3 phosphorylation, which were inhibited by anti-IL-6 and anti-IL-6R treatment. CONCLUSIONS: Our data suggested that IL-6 monoclonal antibody and tocilizumab might effectively abrogate TDI-induced airway inflammation and remodeling, which could be used as a clinical potential therapy for patients with severe asthma.

Prochlorococcus have low global mutation rate and small effective population size.

Prochlorococcus are the most abundant free-living photosynthetic carbon-fixing organisms in the ocean. Prochlorococcus show small genome sizes, low genomic G+C content, reduced DNA repair gene pool and fast evolutionary rates, which are typical features of endosymbiotic bacteria. Nevertheless, their evolutionary mechanisms are believed to be different. Evolution of endosymbiotic bacteria is dominated by genetic drift owing to repeated population bottlenecks, whereas Prochlorococcus are postulated to have extremely large effective population sizes (Ne) and thus drift has rarely been considered. However, accurately extrapolating Ne requires measuring an unbiased global mutation rate through mutation accumulation, which is challenging for Prochlorococcus. Here, we managed this experiment over 1,065 days using Prochlorococcus marinus AS9601, sequenced genomes of 141 mutant lines and determined its mutation rate to be 3.50 × 10-10 per site per generation. Extrapolating Ne additionally requires identifying population boundaries, which we defined using PopCOGenT and over 400 genomes related to AS9601. Accordingly, we calculated its Ne to be 1.68 × 107, which is only reasonably greater than that of endosymbiotic bacteria but surprisingly smaller than that of many free-living bacteria extrapolated using the same approach. Our results therefore suggest that genetic drift is a key driver of Prochlorococcus evolution.

Phonon-Mediated Long-Range Attractive Interaction in One-Dimensional Cuprates.

Establishing a minimal microscopic model for cuprates is a key step towards the elucidation of a high-T_{c} mechanism. By a quantitative comparison with a recent in situ angle-resolved photoemission spectroscopy measurement in doped 1D cuprate chains, our simulation identifies a crucial contribution from long-range electron-phonon coupling beyond standard Hubbard models. Using reasonable ranges of coupling strengths and phonon energies, we obtain a strong attractive interaction between neighboring electrons, whose strength is comparable to experimental observations. Nonlocal couplings play a significant role in the mediation of neighboring interactions. Considering the structural and chemical similarity between 1D and 2D cuprate materials, this minimal model with long-range electron-phonon coupling will provide important new insights on cuprate high-T_{c} superconductivity and related quantum phases.

Risk assessment and source apportionment of trace elements in multiple compartments in the lower reach of the Jinsha River, China.

Studies on trace element (TE) pollution in abiotic matrices have typically focused on water, sediment, and soil, either separately or in pairs. The importance of multi-media connectivity has been ignored. This study analyzed the concentrations of 6 TEs in three connected environmental compartments of a 28-km section of the lower reach of the Jinsha River. The ecological risk posed by TEs was higher in soil than in sediment. The contribution of exposure pathways to human health risk were ranked as ingestion > dermal contact > inhalation. An improved regional environmental risk index (RERI) method was then developed to evaluate the comprehensive risk on both ecology and human health caused by TEs. The average RERI value was generally higher in the wet season (0.42) than in the dry (0.41) and dry-to-wet transition seasons (0.08) because of the combined effects of the high TE concentrations in riparian soil and the long exposure time. Source apportionment indicated that industrial activities, weathering of parent rock, and agricultural activities were possible sources of TEs in this region. The methods and results of this study could inform local environmental management and provide references for similar cases wherein multiple compartments of river systems should be considered.

Anomalously strong near-neighbor attraction in doped 1D cuprate chains.

In the cuprates, one-dimensional (1D) chain compounds provide a distinctive opportunity to understand the microscopic physics, owing to the availability of reliable theories. However, progress has been limited by the challenge of controllably doping these materials. We report the synthesis and spectroscopic analysis of the 1D cuprate Ba2-xSrxCuO3+δ over a wide range of hole doping. Our angle-resolved photoemission experiments reveal the doping evolution of the holon and spinon branches. We identify a prominent folding branch whose intensity fails to match predictions of the simple Hubbard model. An additional strong near-neighbor attraction, which may arise from coupling to phonons, quantitatively explains experiments for all accessible doping levels. Considering structural and quantum chemistry similarities among cuprates, this attraction may play a similarly important role in high-temperature cuprate superconductors.

Identifying molecular pathways and candidate genes associated with knob traits by transcriptome analysis in the goose (Anser cygnoides).

Anser cygnoides has a spherical crest on the beak roof, which is described as knob. However, the mechanisms affecting knob morphology are unclear. Here, we investigated the phenotypic characteristics and molecular basis of knob-size differences in Yangzhou geese. Anatomically, the knob was identified as frontal hump in the frontal area of the skull, rather than hump of upper beak. Although the frontal hump length, and height varied greatly in geese with different knob phenotypes, little was changed in the width. Histologically, knob skin in large-size knobs geese have a greater length in the stratum corneum, stratum spinosum, and stratum reticular than that in small-size knobs geese. Moveover, the 415 differentially expressed genes were found between the large knobs and small ones through transcriptome profiling. In addition, GO enrichment and KEGG pathway analysis revealed 455 significant GO terms and 210 KEGG pathways were enriched, respectively. Among these, TGF-ß signaling and thyroid hormone synthesis-signaling pathways were identified to determine knob-size phenotype. Furthermore, BMP5, DCN, TSHR and ADCY3 were recognized to involve in the growth and development of knob. Our data provide comprehensive molecular determinants of knob size phenotype, which can potentially promote the genetic improvement of goose knobs.

Magic Doping and Robust Superconductivity in Monolayer FeSe on Titanates.

The enhanced superconductivity in monolayer FeSe on titanates opens a fascinating pathway toward the rational design of high-temperature superconductors. Utilizing the state-of-the-art oxide plus chalcogenide molecular beam epitaxy systems in situ connected to a synchrotron angle-resolved photoemission spectroscope, epitaxial LaTiO3 layers with varied atomic thicknesses are inserted between monolayer FeSe and SrTiO3, for systematic modulation of interfacial chemical potential. With the dramatic increase of electron accumulation at the LaTiO3/SrTiO3 surface, providing a substantial surge of work function mismatch across the FeSe/oxide interface, the charge transfer and the superconducting gap in the monolayer FeSe are found to remain markedly robust. This unexpected finding indicate the existence of an intrinsically anchored "magic" doping within the monolayer FeSe systems.

Stabilization of Sr3Al2O6 Growth Templates for Ex Situ Synthesis of Freestanding Crystalline Oxide Membranes.

A new synthetic approach has recently been developed for the fabrication of freestanding crystalline perovskite oxide nanomembranes, which involves the epitaxial growth of a water-soluble sacrificial layer. By utilizing an ultrathin capping layer of SrTiO3, here we show that this sacrificial layer, as grown by pulsed laser deposition, can be stabilized in air and therefore be used as transferrable templates for ex situ epitaxial growth using other techniques. We find that the stability of these templates depends on the thickness of the capping layer. On these templates, freestanding superconducting SrTiO3 membranes were synthesized ex situ using molecular beam epitaxy, enabled by the lower growth temperature which preserves the sacrificial layer. This study paves the way for the synthesis of an expanded selection of freestanding oxide membranes and heterostructures with a wide variety of ex situ growth techniques.

Cryptic speciation of a pelagic Roseobacter population varying at a few thousand nucleotide sites.

A drop of seawater contains numerous microspatial niches at the scale relevant to microbial activities. Examples are abiotic niches such as detrital particles that show different sizes and organic contents, and biotic niches resulting from bacteria-phage and bacteria-phytoplankton interactions. A common practice to investigate the impact of microenvironments on bacterial evolution is to separate the microenvironments physically and compare the bacterial inhabitants from each. It remains poorly understood, however, which microenvironment primarily drives bacterioplankton evolution in the pelagic ocean. By applying a dilution cultivation approach to an undisturbed coastal water sample, we isolate a bacterial population affiliated with the globally dominant Roseobacter group. Although varying at just a few thousand nucleotide sites across the whole genomes, members of this clonal population are diverging into two genetically separated subspecies. Genes underlying speciation are not unique to subspecies but instead clustered at the shared regions that represent ~6% of the genomic DNA. They are primarily involved in vitamin synthesis, motility, oxidative defense, carbohydrate, and amino acid utilization, consistent with the known strategies that roseobacters take to interact with phytoplankton and particles. Physiological assays corroborate that one subspecies outcompetes the other in these traits. Our results indicate that the microenvironments in the pelagic ocean represented by phytoplankton and organic particles are likely important niches that drive the cryptic speciation of the Roseobacter population, though microhabitats contributed by other less abundant pelagic hosts cannot be ruled out.

Lower Expression of Gelsolin in Colon Cancer and Its Diagnostic Value in Colon Cancer Patients.

Colon cancer is one of the most common malignancies causing the majority of cancer-related deaths. Gelsolin (GSN) has been found to be dysregulated in various cancers. However, the secreted GSN in colon cancer remains largely unknown. In the present study, we explored the expression profile of GSN in colon cancer tissues and the diagnostic value of serum GSN in colon cancer. In addition, the effects of secreted GSN in colon cancer cells were studied. We thus found that immunoreactive GSN levels were significantly lower in colon cancer tissues than those in non-tumor colon tissues. Functional studies demonstrated that secreted GSN could restrain cell invasion and migration in vitro. Mechanistically, dose dependent recombinant GSN down-regulated the expression of MMP2 and MMP9, which might restrain the process of cell invasion and migration. Furthermore, serum levels of GSN were significantly lower in colon cancer patients than those in healthy volunteers, and ROC curves showed serum level of GSN had a better diagnostic value for colon cancer (AUC=0.932) than the traditional tumor biomarker Carcinoembryonic Antigen (CEA) or Carbohydrate Antigen 19-9 (CA199). In conclusion, our results suggest that the secreted GSN restrains the invasion and migration of colon cancer cells. Meanwhile, the serum GSN may be a new biomarker for the diagnosis of colon cancer.

Superconducting Tunneling Spectroscopy of Spin-Orbit Coupling and Orbital Depairing in Nb:SrTiO_{3}.

We have examined the intrinsic spin-orbit coupling and orbital depairing in thin films of Nb-doped SrTiO_{3} by superconducting tunneling spectroscopy. The orbital depairing is geometrically suppressed in the two-dimensional limit, enabling a quantitative evaluation of the Fermi level spin-orbit scattering using Maki's theory. The response of the superconducting gap under in-plane magnetic fields demonstrates short spin-orbit scattering times τ_{so}≤1.1 ps. Analysis of the orbital depairing indicates that the heavy electron band contributes significantly to pairing. These results suggest that the intrinsic spin-orbit scattering time in SrTiO_{3} is comparable to those associated with Rashba effects in SrTiO_{3} interfacial conducting layers and can be considered significant in all forms of superconductivity in SrTiO_{3}.