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Heterogeneous advanced oxidation processes (AOPs) based on non-radical reactive species are considered as a powerful technology for wastewater purification due to their long half-lives and high adaptation in a wide pH range. Herein, we fabricate surface Co defect-rich spinel ZnCo2O4 porous nanosheets, which can generate ≡CoIV=O and 1O2 over a wide pH range of 3.81–10.96 by the formation of amphoteric ≡Zn(OH)2 in peroxymonosulfate (PMS) activation process. Density functional theory (DFT) calculations show Co defect-rich ZnCo2O4 possesses much stronger adsorption ability and more electron transfer to PMS. Moreover, the adsorption mode changes from terminal oxygen Co–O–Co to Co–O, accelerating the polarization of adjacent oxygen, which is beneficial to the generation of ≡CoIV=O and 1O2. Co defect-rich ZnCo2O4 porous nanosheets exhibit highly active PMS activation activity and stability in p-nitrophenol (PNP) degradation, whose toxicity of degradation intermediates is significant reduction. The Co defect-rich ZnCo2O4 nanosheet catalyst sponge/PMS system achieved stable and efficient removal of PNP with a removal efficiency higher than 93% over 10 h. This work highlights the development of functional catalyst and provides an atomic-level understanding into non-radical PMS activation process in wastewater treatment. [ABSTRACT FROM AUTHOR]

Duck enteritis virus (DEV) may lead to vascular injury, gastrointestinal mucosal erosion, lymphoid organ injury, and Polyinosinic-polycytidylic acid (Poly I:C) has an antiviral effect by inducing low levels of interferon. The purpose of this study was to explore the pathogenesis of DEV-induced intestinal injury in ducks and to verify the therapeutic effects of different concentrations of Poly I:C. In this study, duck enteritis model was established by infecting healthy Pekin ducks with DEV. Duck intestinal tissues were extracted from normal control group, model group, and treatment group with different doses of Poly I:C. In vivo, HE and TUNEL staining were used to observe the morphological changes and apoptosis. In vitro, the proliferation and apoptosis of duck intestinal epithelial cells were evaluated by MTT assay, TUNEL staining, and flow cytometry. The results showed that Poly I:C protected ducks from DEV toxicity by improving intestinal morphology and inhibiting apoptosis. In addition, the antiviral effect of Poly I:C on DEV was found in a dose-dependent manner, with a more relatively obvious effect at a high dose of Poly I:C. All in all, these results demonstrated that Poly I:C played a vital role in the apoptosis induced by DEV in ducks and modest dose of Poly I:C treatment worked well and may provide important reference for the development of new antiviral drugs in the future. [ABSTRACT FROM AUTHOR]

Over the past few decades, lead selenide (PbSe) thin films have been widely utilized in infrared photonic devices owing to their narrow band gap, large exciton Bohr radius, high carrier mobility and large dielectric constant. The doping of PbSe thin films has presented an intriguing possibility for tuning their band gap and absorption spectrum range. In this study, we present a “one-step” synthesis of calcium-doped PbSe thin films using the chemical bath deposition method, aiming to address the challenges associated with complex processes and expensive elements. We investigate the effects of dopant concentration on the crystal structure, optical properties, and photoelectric properties. At a dopant concentration of 5 mmol/L, the preferred (200) peak shifts towards higher angle direction. Upon sensitization with iodine, an iodine-rich PbI2 phase forms on the top layer of the film, leading to increased barrier heights and efficient electron trapping within the PbI2/PbSe structure. Furthermore, we study the resistance as a function of illumination duration in pristine PbSe, PbSe-Ca and PbSe-Ca-I. Our results show that the resistance change rate of PbSe-Ca is 8%, double that of the pristine PbSe. After sensitization, the resistance change rate increases to 13.82–10.6%, which is 4 times higher than that of the pristine PbSe. These findings demonstrate that Ca-doping combined with iodine sensitization can significantly enhance the photoelectric performance of PbSe thin films. This work presents a new opportunity for the application of lead chalcogenides in optoelectronic devices, which undoubtedly generate substantial interest in fundamental investigations of these materials. [ABSTRACT FROM AUTHOR]

As a core transcriptional factor regulating pluripotency, Krüppel-like factor 4 (KLF4) has gained much attention in the field of stem cells during the past decades. However, few research have focused on the function of KLF4 during human primordial germ cell (PGC) specification. Here, we induced human PGC-like cells (hPGCLCs) from human embryonic stem cells (hESCs) and the derived hPGCLCs upregulated PGC-related genes, like SOX17, BLIMP1, TFAP2C, NANOS3, and the naïve pluripotency gene KLF4. The KLF4-knockout hESCs formed typical multicellular colonies with clear borders, expressed pluripotency genes, such as NANOG, OCT4, and SOX2, and exhibited no differences in proliferation capacity compared with wild type hESCs. Notably, KLF4 deletion in hESCs did not influence the induction of PGCLCs in vitro. In contrast, overexpression of KLF4 during PGC induction process inhibited the efficiency of PGCLC formation from hESCs in vitro. Overexpression of KLF4 may regenerate the naïve ground state in hESCs and results in repression for PGC specification. Thus, KLF4 could be a downstream target of human PGC program and the upregulation of KLF4 is prepared for late stage of germline development. [ABSTRACT FROM AUTHOR]

Survival causal effect estimation based on right-censored data is of key interest in both survival analysis and causal inference. Propensity score weighting is one of the most popular methods in the literature. However, since it involves the inverse of propensity score estimates, its practical performance may be very unstable, especially when the covariate overlap is limited between treatment and control groups. To address this problem, a covariate balancing method is developed in this paper to estimate the counterfactual survival function. The proposed method is nonparametric and balances covariates in a reproducing kernel Hilbert space (RKHS) via weights that are counterparts of inverse propensity scores. The uniform rate of convergence for the proposed estimator is shown to be the same as that for the classical Kaplan–Meier estimator. The appealing practical performance of the proposed method is demonstrated by a simulation study as well as two real data applications to study the causal effect of smoking on survival time of stroke patients and that of endotoxin on survival time for female patients with lung cancer respectively. [ABSTRACT FROM AUTHOR]

Tertiary lymphoid structures (TLSs) play a crucial role in determining prognosis and response to immunotherapy in several solid malignancies. Nevertheless, the effect of TLS-associated gene signature based on The Cancer Genome Atlas (TCGA) cohort in patients with breast cancer (BRCA) remains controversial. Based on TCGA-BRCA dataset (n = 866), 9-gene was identified to construct an TLS signature and further analyzed its prognostic value. Then, we explored the relationship of this TLS signature with molecular subtype, immune microenvironment, tumor mutational burden (TMB). High-TLS signature patients had a better overall survival (OS) than low-TLS signature patients, consistent with the results in the METABRIC cohort. Multivariate analysis revealed that TLS signature remained an independent prognostic indicator for OS. In addition, we established a nomogram with the integration of TLS signature and other independent variables to predict individual risk of death. The comprehensive results showed that patients with high TLS signature benefit from immunotherapy; the signature was also correlated with inhibition of cell proliferation pathways, low TP53 mutation rate, high infiltration of B cells, CD8 + T cells, CD4 + T cells, and M1 macrophages. Therefore, TLS signature is a promising biomarker to distinguish the prognosis and immune microenvironment in BRCA. [ABSTRACT FROM AUTHOR]

Doping of β-Ga2O3 with Al atoms provides an effective approach for further enlargement of the energy bandgap, and enhanced detection in the deep ultraviolet region. Although Al-doped β-Ga2O3 films have been prepared with various methods, challenges remain in the adjustment of crystal quality to obtain superior properties. In this paper, (AlxGa1–x)2O3 (denoted as AGO) films were deposited by magnetron co-sputtering at different bias voltages and annealed at 900°C in air. The dependence of the crystal structure, morphology, and optical properties of the films on bias voltage was investigated. The AGO films exhibit a preferred orientation in the ( 2 ¯ 01) plane at various biases, as evidenced by the x-ray diffraction measurements. The films with various bias voltages yield higher crystal quality with optical bandgap of about 5.0 eV. In addition, the AGO films demonstrate 95% absolute average transmittance in the UV-Vis wavelength range. This method thus opens a new way for controlling the quality and properties of AGO films with bias. [ABSTRACT FROM AUTHOR]

Equitable access to sports services has drawn much attention from policymakers and planners in China, as rapid urbanization and lifestyle changes have caused the pandemic of inactivity. An accurate measure of accessibility will enable the spatial equity of public facility allocation. Existing approaches to measure the spatial accessibility of sports facilities tend to ignore the heterogeneity in potential users' preferences for facilities, thereby causing a bias in the measurement of accessibility. This paper proposes a multi-preference Gaussian two-step floating catchment area (MG2SFCA) method to measure the spatial accessibility of sports facilities, taking into account different travel modes, catchment sizes, and facility preferences among different age groups. Empirically, we adopted the MG2SFCA method in examining the spatial accessibility of sports facilities among children, young working-age population, old working-age population, and elderly population under walking, cycling, and driving modes in Dongguan. The results indicated a significant spatial disparity in the accessibility to sports facilities, with better accessibility in the north and poorer accessibility in the south. Children have the best access to sports facilities, followed by old working-age population, young working-age population, and older population. In the comparison among different transport modes, the accessibility distribution of sports facilities in walking mode showed the greatest spatial variation, while accessibility in driving mode was the most balanced. The MG2SFCA method is superior to the traditional Gaussian 2SFCA method because the former can capture disadvantaged people's actual needs for sports facilities more accurately than the latter. [ABSTRACT FROM AUTHOR]

Macrozoobenthos and submerged macrophytes interact closely. However, studies in China have focused on the middle and lower reaches of the Yangtze River, where shallow lakes are concentrated, rather than on temperate lakes. To clarify the responses of taxonomic and functional groups of macrozoobenthos in temperate lakes to changes in submerged macrophyte biomass (BMac) on a large scale, 19 temperate lakes within Baiyangdian Lake were investigated in this study. The BMac differed greatly across the 19 lakes, and Potamogeton crispus was the dominant species. According to the BMac, the 19 lakes were divided into 4 groups. One-way analysis of variance and Pearson correlation analysis showed that the water environmental parameters were different among the 4 groups, and the BMac was significant correlated with all the physical and chemical parameters of water bodies (except for water depth). Forty-one taxa of macrozoobenthos were identified in the 19 lakes, with oligochaetes, Hirudinea, gastropods, crustaceans, chironomid larvae, and aquatic insects (excluding chironomid larvae) represented by 9, 1, 4, 2, 19, and 6 species, respectively. Chironomid larvae and oligochaetes dominated by density, and gastropods and chironomid larvae dominated by biomass. Canonical correspondence analysis showed that the BMac was the most important factor affecting the macrozoobenthos community structure in group 1 to group 4. Macrozoobenthos with low pollution tolerance values were mainly found in areas with high BMac, while species with high pollution tolerance values were mainly distributed in areas with low BMac and high nutrient contents. Different taxonomic and functional groups of macrozoobenthos responded differently to changes in BMac. As BMac increased, density and biomass of oligochaetes and chironomid larvae tended to decrease, while those of gastropods and aquatic insects tended to first decrease and then increase. Collectors had more species than any other functional group in group 1 to group 4. As BMac increased, density and biomass of collectors gradually decreased, while density of predators, shredders, and scrapers tended to first decrease and then increase. [ABSTRACT FROM AUTHOR]

A predominant objective in wheat breeding is improving yield-related traits. The homeodomain-leucine zipper (HD-Zip) transcription factor plays a significant role in plant growth and development. In this study, we cloned all homeologs of TaHDZ34, which is a member of the HD-Zip class IV transcription factor family in wheat (Triticum aestivum L.). Sequence polymorphism analysis showed that TaHDZ-A34, TaHDZ-B34, and TaHDZ-D34 formed five, six, and six haplotypes, respectively, and the genes were divided into two main haplotype groups. We also developed functional molecular markers. The TaHDZ34 genes were divided into eight main haplotype combinations. Association analysis and distinct population validation preliminarily indicated that TaHDZ34 genes modulate grain number per spike, effective spikelet number per spike, thousand kernel weight, and flag leaf area per plant in wheat. Hap-ABD was the most effective haplotype combination of TaHDZ34. Subcellular localization showed that TaHDZ-A34 was localized to the nucleus. The interacting proteins of TaHDZ-A34 were involved in protein synthesis/degradation, energy production and transportation, and photosynthesis. Geographic distribution and frequencies of TaHDZ34 haplotype combinations suggested that Hap-Abd and Hap-AbD were preferentially selected in Chinese wheat breeding programs. The high-yield-related haplotype combination Hap-ABD provided beneficial genetic resources for the marker-assisted selection of new wheat cultivars. [ABSTRACT FROM AUTHOR]

The ternary Pb–SnSe thin films were prepared using chemical bath deposition (CBD) and sensitized with iodine. The chemical formula of the films was recognized as Pb0.8Sn0.2Se, according to the stoichiometric ratio. The films are both centered cubic crystal structure and show preferred orientation in PbSe (200). The optical band gap (Eg) is found to decrease after sensitization, due to the impurity energy levels created by PbI2. The photoelectric performance of the Pb0.8Sn0.2Se thin films is significantly improved after iodine sensitization. Accordingly, the resistance change rate, i.e., the photoelectric sensitivity is enhanced over 35%, which is over 161% for more than 4 on/off cycles. The density of states (DOS) of Pb0.8Sn0.2Se is calculated using the first-principle method. The calculation shows that the I dangling bond in sensitized Pb0.8Sn0.2Se introduces a large DOS inside the band gap and causes the narrowing of the band gap. [ABSTRACT FROM AUTHOR]

Background: Cloning and characterizing the drought-inducible promoters is essential for their use in crop resistance's genetic improvement. Previous studies have shown that the TaNRX1-D gene participates in regulating the response of wheat to drought stress. However, its promoter has not yet been identified. Objective: In this study, we aimed to characterize the promoter of the TaNRX1-D gene. Methods: The promoter of TaNRX1-D (named P0, 2081 bp) was isolated from common wheat with several cis-acting elements that regulate in response to abiotic stresses and some core cis-acting elements. Functional verification of the promoter, eight 5′-deletion fragments of TaNRX1-D promoter, was fused to the β-glucuronidase (GUS) gene P0::GUS ~ P7::GUS and transformed into Arabidopsis, respectively. Agrobacterium-mediated GUS transient assay the P6a and P6b promoter regions in tobacco leaves under normal, osmotic or ABA stress. Results: Activity analysis of the full-length promoter (P0) showed that the intensity of stronger β-glucuronidase (GUS) staining in the roots and leaves was obtained during the growth of transgenic Arabidopsis. P0::GUS displayed the GUS activity was much higher in the roots and leaves than in other parts of the transgenic plant under normal conditions, which was similarly within wheat. Analysis of the 5′-deletion fragments revealed that P0::GUS ~ P6::GUS responded well upon exposure to osmotic (polyethylene glycol-6000, PEG6000) and abscisic acid (ABA) stress treatments and expressed significantly higher GUS activity than the CaMV35S promoter (35S::GUS), while P7::GUS did not. GUS transient assay in tobacco leaves showed that the GUS activities of P6a and P6b were lower than P6 in the PEG6000 and ABA stresses. Conclusion: The 193 bp (P6) segment was considered the core region of TaNRX1-D responding to PEG6000 or ABA treatment. GUS activity assay in transgenic Arabidopsis showed that this segment was sufficient for the PEG6000 or ABA stress response. The identified 193 bp promoter of TaNRX1-D in this study will help breed osmotic or ABA tolerant crops. The 36 bp segment between P6 and P6b (−193 to −157 bp) was considered the critical sequence for the TaNRX1-D gene responding to PEG6000 or ABA treatment. [ABSTRACT FROM AUTHOR]

Photoperiod (Ppd) genes play an important role in the adaptation of wheat to the ecological environment. However, the transcriptional regulation mechanism of photoperiodic genes has remained elusive. This study isolated a full-length promoter of Ppd-D1b (2518 bp) from the common wheat genome. Several essential core cis-acting elements and numerous light-responsive cis-acting regulatory elements were identified in Ppd-D1b promoter by the in-silico analysis. Ten 5'-deleted length fragments of the Ppd-D1b promoter fused with GUS were constructed and named D0 ~ D9, then transferred them into Arabidopsis thaliana. GUS gene driven by full-length (D0) in transgenic Arabidopsis thaliana showed the same rhythm with Ppd-D1b in wheat under short-day conditions (SDs, 8-h light/16-h dark). The expression of GUS gene in D0 reached its peak at 3 h after dawn, then decreased to the lowest and remained stable. Analysis of the series of 5'-deleted fragments showed that at 3 h after dawn, GUS gene expression activity decreased significantly in D7a due to removal of CHEBS (CCA1 HIKING EXPEDITION binding site). Moreover, yeast one-hybrid (Y1H) and dual-luciferase (dual-LUC) assays revealed that TaTCP20 could bind to the Ppd-D1b promoter to increase its transcriptional activity. This study revealed a transcription factor, TaTCP20, which activated Ppd-D1b by binding to CHEBS, provided a foundation for the theoretical research on wheat's photoperiodic response mechanism. [ABSTRACT FROM AUTHOR]

The mitochondrion is an important sub-cellular organelle responsible for the cellular energetic source and processes. Owing to its unique sensitivity to heat and reactive oxygen species, the mitochondrion is an appropriate target for photothermal and photodynamic treatment for cancer. However, targeted delivery of therapeutics to mitochondria remains a great challenge due to their location in the sub-cellular compartment and complexity of the intracellular environment. Herein, we report a class of the mitochondrion-targeted liposomal delivery platform consisting of a guanidinium-based dendritic peptide moiety mimicking mitochondrion protein transmembrane signaling to exert mitochondrion-targeted delivery with pH sensitive and charge-reversible functions to enhance tumor accumulation and cell penetration. Compared to the current triphenylphosphonium (TPP)-based mitochondrion targeting system, this dendritic lipopeptide (DLP) liposomal delivery platform exhibits about 3.7-fold higher mitochondrion-targeted delivery efficacy. Complete tumor eradication is demonstrated in mice bearing 4T1 mammary tumors after combined photothermal and photodynamic therapies delivered by the reported DLP platform. Mitochondria are key targets for photothermal and photodynamic treatment for cancer but delivery of therapeutics to these organelles remains a challenge. In this study, authors develop a mitochondrial targeted liposomal delivery platform using a dendritic peptide moiety as a mitochondria targeting moiety and demonstrate its targeting and antitumour efficacy in a mouse model of breast cancer. [ABSTRACT FROM AUTHOR]

Precipitation use efficiency (PUE) is crucial in understanding the coupling between ecosystem carbon and water cycling. In this study, we used a time series (2000–2013) dataset of net primary productivity (NPP) based on the Carnegie–Ames–Stanford Approach (CASA) model together with precipitation to reveal the spatial and temporal patterns of alpine grassland PUE in Northern Tibet. The mean annual PUE values of alpine meadow, alpine meadow steppe, alpine steppe, alpine desert steppe, and alpine desert were 0.48, 0.39, 0.36, 0.29 and 0.23 gc m−2 mm−1, respectively. The spatial patterns of PUE of alpine grassland demonstrated an initial increase in the arid region and a subsequent decrease in the humid region along the precipitation gradient and peaked at approximately 500 mm. To evaluate the temporal patterns, the sensitivity Slope and the Pearson correlation coefficient R xy between the PUE and climatic factors were calculated. The inter-annual variability of PUE exhibited a significant negative correlation with annual precipitation (P < 0.05), which implies that NPP had a lower sensitivity to precipitation in most regions. The relationship between PUE and the mean annual temperature is different for different regions. Our findings have an important role in understanding the impacts of precipitation availability on climate change and in the scientific management of the alpine grassland ecosystems. [ABSTRACT FROM AUTHOR]

Effect of crop row spacing on the belowground ecosystem, especially at an aggregate scale, remains unexplored. To explore how row spacing influenced nematode community and ecosystem function at the aggregate scale, four row spacings i.e. equidistant-row (ER, 50 cm-inter-row distance, 33 cm-intra-row between plants in each row) and non-equidistant-row including NR1 (100 cm + 50 cm row distance and 22 cm intra-row), NR2 (100 cm + 50 cm inter-row and 25 cm intra-row), and NR3 (60 cm + 40 cm inter-row and 33 cm intra-row) were compared, and four soil aggregate fractions i.e. >2 mm, 1–2 mm, 0.25–1 mm and <0.25 mm were separated. Row spacing did not impact C and N, but significantly influenced P. The regulation effect of acid phosphatase on soil available P was aggregate-scale dependent. Nematode faunal analysis indicated that NR3 within 0.25–1 mm was less disturbed or relatively undisturbed environments. Structural equation model showed row spacing pattern directly affected multifunctionality, while aggregate fractions indirectly contributed to multifunctionality mainly by regulating the richness of total nematodes and trophic groups. It was concluded that NR3 had potential to construct more stable food web, and therefore was possibly the suitable planting pattern. [ABSTRACT FROM AUTHOR]

This article suggests that variations in the dominant pattern of innovation policy coordination can be analysed and understood effectively by dividing innovation and other complementary socio-economic policies into low-complexity and high-complexity tasks. The effective implementation of these two sets of policy tasks that differ in the extent, nature and intractability of collective action problems confronting the coordination process hinges on the strength of two sociopolitical institutions: bureaucratic organizational structures and interactive governing arrangements. While bureaucratic organizational structures are better suited to delivering low-complexity tasks, interactive governing arrangements are more effective in resolving high-complexity policy problems. They interact differently across political economies to structure the management of coordination challenges and thus give rise to divergent patterns of innovation policy-making. The comparative analysis of innovation policy coordination between Hong Kong and Singapore over the past two decades lends strong support to the central theoretical propositions of the article. [ABSTRACT FROM AUTHOR]

Hyperspectral images (HSIs) have great potential in military reconnaissance, land use, marine monitoring and many other fields. In recent years, the convolutional neural network (CNN) has been successfully used to classify hyperspectral data and achieved remarkable performance. However, the limited labeled samples of HSI lead to the small sample size problem, which remains the major challenge for CNN-based HSI classification. Besides, most CNN models have large number of parameters needed to be learned, which cause high computational cost. To address the aforementioned two issues, a novel CNN-based HSI classification method is proposed. The proposed classification method has several distinguishing characteristics. First, the proposed method can robustly extract spectral and spatial features of the HSI simultaneously. Second, in the proposed CNN architecture, all convolution layers are 1 × 1 convolution layer except the first one, which can greatly reduce the number of network parameters, thus accelerating the training and testing process. Third, a small convolution and feature reuse (SC-FR) module is developed. The SC-FR module is composed of two composite layers and each composite layer consists of two cascaded 1 × 1 convolution layers. Through cross-layer connecting, the input and output features of each composite layer are concatenated and passed to the next convolution layer, thus achieving feature reuse mechanism. Cross-layer connection increases information flow and the utilization rate of middle-level features, which enhances the generalization performance of CNN effectively. Experimental results on three benchmark HSIs demonstrate the competitive superiority of the proposed method over several state-of-the-art HSI classification methods, especially when training samples are limited. [ABSTRACT FROM AUTHOR]

Plant roots in lakeshore areas can directly determine the survival of the aboveground plant parts. However, most current studies are focused on the aerial shoots, and less attention has been paid to the functions of the roots. In order to evaluate the effects of water level fluctuations (WLFs) on root architectural and morphological traits of plants in lakeshore areas, field investigations were conducted seasonally in three subtropical floodplain lakes with different types of WLFs. The results showed that both the pH and moisture contents of the soils were significantly different in all seasons among the three lakes, while the total nitrogen and total phosphorus in the soils only showed significant differences in certain seasons. Significant differences were also found in the two architectural trait parameters (root length density and root branching number) and three morphological trait parameters (root tissue density, root surface area, and root volume), all of which (except for root tissue density) were highest in the Dahuchi lake that experiences intermittent WLFs, and lowest in the Chaohu Lake with reservoir-like WLFs. With increasing lakeshore elevation gradients, we found that root length density, root branching number, root surface area, and root volume in the three lakes changed significantly, and all these root trait parameters increased first and then decreased. However, no significant differences were found for the above four root traits in the three lakes over the different seasons. Spearman correlation analyses indicated that both the hydrological and physicochemical factors were strongly correlated with the architectural and morphological root trait parameters, and the duration of submergence (duration) was the most important factor, judging from the correlation coefficients (R). The results of stepwise multiple regression further indicated the duration was the key factor affecting plant root traits. Based on the results of this study, we suggest that the WLFs in reservoir-like lakes should be changed in order to improve the ecological functions of the lakeshore. [ABSTRACT FROM AUTHOR]

Developing multifunctional nanoparticles to support new therapy models is a promising and challenging task to address the current dilemma on antitumor treatment. Herein, we incorporated multifunctional dendritic nanoparticles into a poly(D,L-lactide-co-glycolide)-poly(ethylene glycol)-poly(D,L-lactide-co-glycolide) (PLGA-PEG-PLGA) triblock copolymers thermosensitive injectable hydrogel matrix to construct a localized drug delivery system for combining chemotherapy and immunotherapy. The multifunctional dendritic nanoparticles were designed with following expectations: i, Dendritic scaffolds provide a hydrophobic interior to load the anticancer drug, doxorubicin (DOX), for chemotherapy; and ii, dendritic scaffolds are used to build arginine-rich molecules to provide the inducible nitric oxide synthase (iNOS) substrate, L-Arg, to M1 macrophages, which can produce the cytotoxic substance nitric oxide (NO) and subsequently induce tumor cell destruction through immunotherapy. It is noteworthy that the dendritic nanoparticles-in-hydrogel delivery system is able to gel at physiological temperature and serves as a warehouse for the sustained release of the drug. Ultimately, this system showed great efficacy in treating 4T1 cells-xenografted BALB/C mice (86.62% tumor growth inhibition). Therefore, this localized drug delivery system combining chemotherapy and immunotherapy provides a novel approach for cancer therapy. [ABSTRACT FROM AUTHOR]

Background and aims: Crop residue decomposition is a major component of carbon (C) cycling and provides energy and nutrients to the soil micro-food web. An in-situ field experiment was conducted to examine how exogenous organic C is incorporated into the soil micro-food web and how this is influenced by four different fertilization treatments: organic manure (M), urea fertilizer (U), the combined application of organic and urea fertilizer (MU) and unfertilized control.Methods: The amount of 13C-enriched maize remained was traced in microbial phospholipid fatty acids (PLFAs) and in different trophic groups of the soil nematode community after a 183-day decomposition period.Results: The fertilization type influenced the incorporation of residue into the microbial community. Soil bacterial and fungal PLFAs utilized the least 13C-labeled crop residues in the U treatment. Both the nematode bacterial and the fungal pathways utilized more crop residues in the M treatment than in other treatments.Conclusions: Given the ecological services provided by the soil organisms, our results suggest that long-term manure application increases the soil C pool directly. This also leads to more C from crop residues utilized by the soil food web, which in turn, can benefit crop growth or C accumulation in agroecosystems. [ABSTRACT FROM AUTHOR]

Zizania latifolia is a common emergent macrophyte that plays an important role in the ecological restoration of lakes in the middle and lower reaches of the Yangtze River basin. To understand the mechanisms behind the relative changes in the distribution of Z. latifolia in the field, we analyzed the effects of water depth and substrate type on rhizome bud sprouting (RBS) and growth in Z. latifolia through simulation experiments. Four water depths (0, 30, 60, and 90 cm) and three substrate types (sandy loam, clay loam, and silt) were used. The results showed that: (1) water depth significantly affected the RBS, and the RBS percentage significantly decreased with increasing water depth. However, substrate type and its interaction with water depth had no effect on RBS. (2) Two-way analysis of variance (ANOVA) showed that plant height, stem diameter, and root length were significantly affected by water depth, with the highest values observed at a water depth of 0 cm. Only root length was significantly affected by substrate type and its interaction with water depth, and it was highest in silt. (3) Both water depth and its interaction with substrate type had significant effects on total biomass and the root:shoot ratio in Z. latifolia, but no significant effect was found when it came to subtrate type. The results of this study will be useful for the ecological restoration of lakes in the middle and lower reaches of the Yangtze River basin. [ABSTRACT FROM AUTHOR]

Background and aims: Nitrogen (N) is one of the most important limiting factors influencing plant growth and reproduction in alpine and tundra ecosystems. However, in situ observations of the effects of root traits on N absorption by alpine plant species are still lacking.Methods: We investigated the rates of N uptake and the effect of root characteristics in ten common herbaceous alpine plant species using a 15N isotope tracer technique and the root systems of plants growing in a semi-arid steppe environment on the Tibetan Plateau. Our objective was to determine the root traits (root biomass, volume, surface area, average diameter, length, specific root length and specific root area) that make the largest contribution to the total uptake of N (15N-NO3−, 15N-NH4+ or 15N-glycine) by alpine plant species.Results: Monocotyledonous species had higher absorption rates for 15N-NH4+, 15N-NO3−, 15N-glycine and total 15N than dicotyledonous species (P < 0.05). The root biomass, volume, surface area and average diameter were negatively correlated with the absorption capacity for 15N-NH4+, 15N-NO3− and total 15N across the ten alpine plant species. However, the specific root length and the specific root area had significantly positive effects on the uptake of N.Conclusions: In contrast with traditional views on the uptake of N, the N uptake rate was not improved by a larger root volume or root surface area for these alpine plant species in a high-altitude ecosystem. Root morphological traits had greater impacts on N absorption than traits related to the root system size in alpine herbaceous plants. [ABSTRACT FROM AUTHOR]

Functional data analysis (FDA) is concerned with inherently infinite-dimensional data objects and therefore can be viewed as part of the methodology for big data. The size of functional data may vary from terabytes as encountered in functional magnetic resonance imaging (fMRI) and other applications in brain imaging to just a few kilobytes in longitudinal data with small or modest sample sizes. In this contribution, we highlight some applications of FDA methodology through various data illustrations. We briefly review some basic computational tools that can be used to accelerate implementations of FDA methodology. The analyses presented in this paper illustrate the principal analysis by conditional expectation (PACE) package for FDA, where our applications include both relatively simple and more complex functional data from the biomedical sciences. The data we discuss range from functional data that result from daily movement profile tracking and that are modeled as repeatedly observed functions per subject, to medfly longitudinal behavior profiles, where the goal is to predict remaining lifetime of individual flies. We also discuss the quantification of connectivity of fMRI signals that is of interest in brain imaging and the prediction of continuous traits from high-dimensional SNPs in genomics. The methods of FDA that we demonstrate for these analyses include functional principal component analysis, functional regression and correlation, the modeling of dependent functional data, and the stringing of high-dimensional data into functional data and can be implemented with the PACE package. [ABSTRACT FROM AUTHOR]

The mechanisms for maintaining the species diversity of plant communities under conditions of resource limitation is an important subject in ecology. How interspecific relationships influence the pattern of nutrient absorption by coexisting species in N-limited ecosystems is still disputed. We investigated the effect of neighbor species on the uptake of inorganic and organic N by three common plant species using N tracer techniques in a semi-arid alpine steppe on the northern Tibet. The results showed that the plant species varied in their capacity to absorb NO -N, NH -N, and glycine-N with or without neighbor species. Carex moorcroftii and Leontopodium nanum showed much more plasticity in resource utilization than Stipa purpurea when neighbor species were present. When C. moorcroftii and S. purpurea coexisted, they all increased their N uptake for the NO -N ( C. moorcroftii 2.2-fold increase and S. purpurea 2.2-fold increase) and glycine-N treatments ( C. moorcroftii 2.9-fold increase and S. purpurea 3.4-fold increase), which indicated that neighborhood had a positive effect for N absorption between the two species. However, L. nanum was a less effective competitor for N utilization than the neighbor species across almost all treatments. The dominant species appeared to have an inhibitory effect on N absorption by the accompanying species in this alpine steppe environment. Thus, interspecific neighbor pairs may result in both a mutually beneficial cooperative relationship and a competitive relationship among neighbors in resource use patterns in extreme environments. Resource use plasticity in altered neighbor species may be due to phenotypic plasticity based on the conditions of the realized niche, offering a valuable insight into niche complementarity and providing a general and important mechanism for resource partitioning in an alpine area. [ABSTRACT FROM AUTHOR]

Traditional time/frequency domain filter-based methods would fail due to the serious overlapping of the communication signal and jamming in time/frequency domain. In order to solve this problem, an anti-jamming algorithm based on single channel source separation by exploiting cyclostationary difference is proposed for direct sequence spread spectrum (DSSS) communication. Firstly, the cyclostationary difference among source signals is used to establish the single channel source separation model based on partial priori information of the DSSS signal. Secondly, cost function of the algorithm is constructed by the training sequences and the minimum mean square error criterion; after that, the optimal separation matrix of the pilot mixed signal can be calculated based on this cost function. Thirdly, the purpose of anti-jamming for DSSS communication can be achieved by separating the communication signal from the service mixed signal based on the optimal separation matrix calculated before. Simulation results show that, compared with the unseparated signal of high bit error rate (BER) close to 0.5, the proposed antijamming algorithm is more effective in anti-jamming with the BER as low as 10, which is not only applicable to narrowband jamming such as the single-tone/multi-tone jamming, but also applicable to broadband jamming such as the sweep-spot jamming. [ABSTRACT FROM AUTHOR]

The Yangtze finless porpoise is a subspecies of narrow-ridged finless porpoise endemic to the middle and lower reaches of the Yangtze River and the adjoining Poyang and Dongting Lakes. With the depletion of fish stocks in the Yangtze River in recent decades, food availability has become the most important factor affecting the survival of this subspecies. Despite this, the relationships between fish community and occurrences of porpoise are far from being fully understood. Therefore, during September 2013 to August 2014, the occurrences of porpoise were investigated in confluence of the Yangtze and Wanhe Rivers; fish community was also surveyed synchronously in confluence and two adjacent transects. The results showed that (1) the confluence had maximum fish species richness, and the main dominant species was upper fish, while the other two transects were mainly dominated by demersal fish. ANOVA analyses showed that individual number and yield of upper fish which can be eaten by porpoise (upper edible fish) in the confluence were significantly higher than other two transects. (2) Average group size of the porpoise was 3.7 ± 1.8 individuals. The occurrences of porpoise in different seasons had great differences, and the porpoise was more likely to be detected in autumn and winter. (3) Fish community had significant effects on occurrences of porpoise, and the main influencing factors were fish species richness, individual number, and yield of edible fish, especially the upper edible fish. The results of this study will have important implications for the conservation of porpoise. [ABSTRACT FROM AUTHOR]

Vegetation communities in floodplain lakes are adapted to natural water regimes. Construction of sluices or dams between rivers and their floodplain lakes will inevitably lead to great changes in plant communities. In order to evaluate the effects of water level fluctuations (WLFs) on lakeshore vegetation in floodplain lakes of the Yangtze River, a field investigation was conducted in two river-disconnected lakes (Wuchang Lake and Shengjin Lake) and one river-connected lake (Shimen Lake). The results showed that plant species richness was highest in the disconnected Shengjin Lake with intermediate amplitude of WLFs, and lowest in the connected Shimen Lake. Species composition differed among the three lakes and the two disconnected lakes with more similar WLFs exhibiting the greatest similarity. Six plant communities were classified using TWINSPAN. Multivariate analyses showed that the amplitude of WLFs was the most important factor in determining the distribution of lakeshore plants, followed by relative elevation and duration of submergence. Our results provide an eco-hydrological basis for plant restoration in the Yangtze floodplain lakes. We suggest that fluctuating amplitude should be increased in lakes with small WLFs, and small habitats with various hydrological regimes should be created in lakes with large WLFs. [ABSTRACT FROM AUTHOR]

Bipolar resistive switching properties of Ag/a-IGZO/Pt structure resistive random-access memories (ReRAMs) were investigated. The amorphous In-Ga-Zn-O (a-IGZO) films were prepared by a radio frequency magnetron sputtering system at room temperature in mixed gas ambient of argon (Ar) and oxygen (O). The oxygen partial pressures during sputtering deposition were varied from 0% to 17% to engineer defects in an a-IGZO layer. When the oxygen partial pressure increased to 17%, forming-free bipolar resistive switching properties were observed with nearly 100% device yield. In addition, the forming-free ReRAM device presents an enhanced resistive switching uniformity and an enhanced endurance. The forming-free resistive switching is attributed to the concentration of oxygen-related defects in an a-IGZO thin film via analyses of x-ray photoelectron spectroscopy and current-voltage ( I- V) curves, with which it is possible to reduce the forming energy of silver (Ag) conductive filaments. [ABSTRACT FROM AUTHOR]

A selective and low organic-solvent-consuming method of sample preparation combined with high-performance liquid chromatography with diode-array detection is introduced for analysis of phthalic acid esters in edible oils. Sample treatment involves initial liquid-liquid partitioning with acetonitrile, then QuEChERS cleanup by dispersive solid-phase extraction with primary secondary amine as sorbent. Preconcentration of the analytes is performed by ionic-liquid-based dispersive liquid-liquid microextraction, with the cleaned-up extract as disperser solvent and 1-hexyl-3-methylimidazolium hexafluorophosphate as extraction solvent. Under the optimized conditions, correlation coefficients ( r) were 0.998-0.999 and standard errors ( S) were 2.67-3.37 × 10 for calibration curves in the range 50-1000 ng g. Detection limits, at a signal-to-noise ratio of 3, ranged from 6 to 9 ng g. Intra-day and inter-day repeatability, expressed as relative standard deviation, were in the ranges 1.0-6.9 % and 2.4-9.4 %, respectively. Recovery varied between 84 % and 106 %. The developed method was successfully used for analysis of the analytes in 28 edible oils. The dibutyl phthalate content of four of the 28 samples (14 %) exceeded the specific migration limit established by domestic and international regulations. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The ascomycete Sclerotinia sclerotiorum is a devastating plant pathogen with a very broad host range. In this study, we developed a loop-mediated isothermal amplification (LAMP) assay targeting the Ssos5 sequence for visual detection of S. sclerotiorum. The LAMP reaction was optimal at 63 °C for 45 min. When hydroxynaphthol blue (HNB) was added before amplification, samples with S. sclerotiorum DNA developed a characteristic sky blue colour but those without DNA or with the DNA of nine other plant-pathogenic fungi did not. Results obtained with LAMP and HNB were confirmed when LAMP products were subjected to gel electrophoresis. The detection limit of this LAMP assay for S. sclerotiorum was 0.1 fg μL of genomic DNA per reaction, while that of conventional PCR was 100 fg μL. Detection results were identical when 13 samples of rapeseed tissue infected with S. sclerotiorum were subjected to LAMP, conventional PCR, and conventional isolation. Because the LAMP assay reported here is simple, rapid, sensitive, and specific, it should be valuable for the detection of S. sclerotiorum in quarantine efforts and field surveys. [ABSTRACT FROM AUTHOR]

A dispersive liquid-liquid microextraction (DLLME) method coupled to high-performance liquid chromatography was developed for the analysis of α-tocopherol in grain samples. The DLLME parameters including the type and volume of extractants, the volume of disperser and the addition of salt were examined. The optimized DLLME procedure consisted in the formation of a cloudy solution promoted by the fast addition to the sample (5 mL of saponified sample solution diluted with 5 mL of water) of a mixture of carbon tetrachloride (extraction solvent, 80 μL) and ethanol (dispersive solvent, 200 μL) without the addition of salt, followed by shaking for 5 min and centrifuging for 3 min at 5,000 rpm. Intra- and inter-day repeatability expressed as % RSD were 3.5 and 7.6 %, respectively. The limit of detection and the limit of quantification were 1.9 and 6.3 μg L. The comparison of this method with the national standardized extraction method, supercritical carbon dioxide extraction, accelerated solvent extraction, and conventional heat-reflux extraction indicates that the DLLME was accurate (no significant differences at the 0.05 % probability level), high efficient, low organic solvent-consuming, and low cost. This procedure was successfully applied to 42 samples of 14 types of purple wheat, for which the content of α-tocopherol exhibited a significantly negative correlation with the pigment content measured by a spectrophotometer. The recovery rates ranged from 90.5 to 103.7 %. [ABSTRACT FROM AUTHOR]

The middle Yangtze Reach is one of the most developed regions of China. As a result, most lakes in this area have suffered from eutrophication and serious environmental pollution during recent decades. The aquatic biodiversity in the lakes of the area is thus currently under significant threat from continuous human activities. Testate amoebae (TA) are benthic (rarely planktonic) microorganisms characterized by an agglutinated or autogenous shell. Owing to their high abundance, preservation potential in lacustrine sediments, and distinct response to environmental stress, they are increasingly used as indicators for monitoring water quality and reconstructing palaeoenvironmental changes. However this approach has not yet been developed in China. This study presents an initial assessment of benthic TA assemblages in eight lakes of Lake Donghu in the region of Wuhan, China. Testate amoeba community structure was most strongly correlated to water pH. In more alkaline conditions, communities were dominated by Centropyxis aculeata, Difflugia oblonga, Pontigulasia compressa, Pon. elisa and Lesquereusia modesta. These results are consistent with previous studies and show that TA could be useful for reconstructing past water pH fluctuations in China. To achieve this, the next step will be to expand the database and build transfer function models. [ABSTRACT FROM AUTHOR]

Osmotic stresses such as drought, salinity, and cold are major environmental factors that limit agricultural productivity. Transcription factors play essential roles in abiotic stress signaling in plants. Three TaMYB2 members were identified and designated TaMYB2A, TaMYB2B, and TaMYB2D based on their genomic origins. The cis-regulatory elements in the promoter regions were compared, and their diverse expression patterns under different abiotic stress conditions were identified. TaMYB2A was further characterized because of its earlier response to stresses. Subcellular localization revealed that TaMYB2A localized in the nucleus. To examine the role of TaMYB2A under various environmental stresses, transgenic Arabidopsis plants carrying TaMYB2A controlled by the CaMV 35S promoter were generated and subjected to severe abiotic stress. TaMYB2A transgenics had enhanced tolerance to drought, salt, and freezing stresses, which were confirmed by the enhanced expressions of abiotic stress-responsive genes and several physiological indices, including decreased rate of water loss, enhanced cell membrane stability, improved photosynthetic potential, and reduced osmotic potential. TaMYB2A is a multifunctional regulatory factor. Its overexpression confers enhanced tolerance to multiple abiotic stresses while having no obvious negative effects on phenotype under well-watered and stressed conditions; thus, TaMYB2A has the potential for utilization in transgenic breeding to improve abiotic stress tolerances in crops. [ABSTRACT FROM AUTHOR]

Vertical distribution of soil nematode communities under conventional tillage (CT), no-tillage (NT) and fallow field (FF) treatments in the Lower Reaches of the Liaohe River was investigated at six soil depths (0–5 cm, 5–15 cm, 15–30 cm, 30–50 cm, 50–75 cm and 75–100 cm). The results show that total nematode abundance gradually decreases with depth, and the highest number of total nematodes is observed at 0–5 cm depth under NT and FF treatments. The number of fungivores and plant parasites is significantly higher under FF and NT treatments than under CT treatment at the 0–5 cm depth. There is significant soil depth effect on the abundances of bacterivores and omnivores-predators, which exhibits a similar trend to that of total nematodes; whereas, no significant tillage effect is found. Tillage effect on soil nematode communities can be reflected by values of relative tillage response of index V. Results of index V indicate that total nematodes, bacterivores, fungivores and plant parasites are mildly inhibited, and omnivores-predators is moderately inhibited under CT treatment; while, under FF treatment total nematodes is mildly, and fungivores and plant parasites are moderately stimulated, respectively. [ABSTRACT FROM AUTHOR]

The effects of inorganic fertilizers on soil nematode communities were studied in a long-term fertilization experimental field in the Black Soil Region of Northeast China, where no fertilizer (CK), N fertilizer (N), combined application of N and P (NP), combined application of N and K (NK), and combined application of N, P and K (NPK) were compared. The results showed that the total nematode abundance was not affected significantly by inorganic fertilizers in the long-term field experiment. The numbers of bacterivores increased significantly in the NP treatment compared to the CK treatment, and those of fungivores and plant-parasites were inhibited in the NPK treatment. The similarity between CK and NPK treatment and the nematode diversity were higher than in other treatments. The stability of the soil ecosystem was disturbed by the inorganic fertilizers, as indicated by the change in MI values under different treatments. The response of soil nematodes mainly depended on the types of inorganic fertilizers applied. [ABSTRACT FROM AUTHOR]

Reduction of plant height has played a significant role in improving wheat production and knowledge of dwarfing genes in Chinese wheat will be very important for developing high yielding cultivars. Molecular markers were used to detect the presence of genes Rht-B1b ( Rht1), Rht-D1b ( Rht2) and Rht8 in 220 wheat genotypes from autumn-sown wheat regions in China. They include landmark landraces, leading cultivars and core parents involved in wheat breeding from the 1950s to the present. Results indicated that Rht-D1b and Rht8 dominate with frequencies of 45.5% and 46.8%, respectively, followed by Rht-B1b with a frequency of 24.5%. The frequencies of Rht-B1b and Rht-D1b increased, from 8.6 to 32.2% and 36.2 to 53.4%, respectively, whereas the frequency of Rht8 has remained constant over time, when compared with cultivars released before and after 1990. This indicates that both the Rht-B1b and Rht-D1b were successfully used in wheat production in Chinese environments. Our study shows that Rht-B1b and Rht-D1b can be used in the post-anthesis heat stressed environments. Rht-B1b in Chinese wheats is derived from two sources, viz., Norin 10 and the Italian introduction St2422/464 ( Rht-B1b and Rht8). The identity of Rht-B1b in these two sources still needs to be confirmed. Suwon 86 carrying both Rht-B1b and Rht-D1b, and Chinese cultivars, Huixianhong and Yaobaomai, are the primary sources of Rht-D1b in Chinese wheats. It is likely that Rht-D1b in Youbaomai derives from an unknown introduction. Italian introductions such as Funo and Abbondanza, and Lovrin 10 with the 1B/1R translocation, and Chinese landraces are the three major sources of Rht8. This information will be very valuable for wheat breeding in China, and internationally. [ABSTRACT FROM AUTHOR]

Flowering time of wheat cultivars contributes greatly to the adaptability to environmental conditions and it is largely controlled by vernalization genes. In this study, 262 Chinese mini-core wheat cultivars were used to identify the allelic variation at VRN-B1 locus. A novel dominant allele Vrn-B1d was found in Chinese spring wheat landrace cultivar Hongchunmai. This allele contained several genetic divergence within the first intron comparing to the recessive allele vrn-B1, including one large 6850-bp deletion (670-7519 bp), one small 187-bp deletion (7851-8037 bp), one unique SNP (T to C, 7845 bp), and one 4-bp mutation (TTTT to ACAA, 7847-7850 bp). Meanwhile, it was also different from the three known dominant alleles at VRN-B1 locus. Two pairs of primers were designed to identify the novel allele Vrn-B1d and other four known alleles of VRN-B1. A multiplex PCR was established to discriminate all five alleles simultaneously. The greenhouse experiment with high temperature (non-vernalizing condition) and long light showed that F2 plants containing Vrn-B1d allele headed significantly earlier than those with recessive vrn-B1 allele, suggesting that Vrn-B1d is a dominant allele conferring the spring growth habit. This study provides a useful germplasm and molecular markers for wheat breeding. [ABSTRACT FROM AUTHOR]