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Decreased dietary protein intake (DPI) may lead to protein-energy malnutrition and may be associated with increased mortality risk. We hypothesized that longitudinal changes in dietary protein intake have independent associations with survival in peritoneal dialysis (PD) patients. 668 stable PD patients were selected in the study from January 2006 to January 2018 and were followed up until December 2019. Their three-day dietary records were collected at the baseline (the sixth month after PD) and thereafter every 3 months for two and a half years. The latent class mixed models (LCMM) were used to identify subgroups of PD patients with similar longitudinal trajectories of DPI. The relation between DPI (baseline and longitudinal data) and survival was examined using Cox model to estimate death hazard ratios. Meanwhile, different formulae were used to assess nitrogen balance. The results showed that baseline DPI ≤ 0.60g/kg/day was associated with the worst outcome in PD patients. Patients with DPI 0.80–0.99g/kg/day and DPI ≥ 1.0g/kg/day both presented positive nitrogen balance; patients with DPI 0.61–0.79g/kg/day presented obviously negative nitrogen balance. Longitudinal association between time-dependent DPI and survival was found in PD patients. The consistently low DPI' (0.61–0.79g/kg/d) group was correlated with increased death risk as compared with the 'consistently median DPI' group (0.80–0.99g/kg/d, HR = 1.59, p = 0.008), whereas there was no difference in survival between 'consistently median DPI' group and 'high-level DPI' group (≥1.0 g/kg/d, p > 0.05). Our study revealed that DPI ≥ 0.8 g/kg/day was beneficial to the long-term outcome for the PD population. [ABSTRACT FROM AUTHOR]

The levels of the chlorinated organic compound Dechlorane Plus (DP) are increasing in aquatic ecosystems. To investigate the adverse effects of DP on aquatic animals, common carp (Cyprinus carpio) were subjected to three different DP concentrations (30 μg L−1, 60 μg L−1, and 120 μg L−1) for 1 d, 15 d, and 30 d. Histology and the hepatic and cerebral expression levels of several key antioxidant, detoxification, and apoptotic factors were then examined. Histopathological inspections showed that the liver and brain were severely damaged in carp exposed to 60 μg L−1 and 120 μg L−1 DP. Relative to the controls, the superoxide dismutase and glutathione activity levels and the malondialdehyde content were also changed in livers and brains exposed to DP. Besides, significant alterations in the expression levels of the inflammatory cytokines IL-1β, IL-6, and IL-10 were observed in the livers of carp subjected to DP. Relative to the control, the brains of DP-exposed carp presented with significantly upregulated IL-1β and IL-6 in carp treated with 120 μg L−1 DP for 30 d. The transcription levels of hepatic cyp2b4, cyp1b1, and cyp3a138 were all increased compared with the untreated at all DP exposure concentrations. The aforementioned results suggest that DP exposure perturbs fish metabolism and causes liver injury by inhibiting antioxidant enzyme activity, increasing lipid peroxidation, promoting inflammation, and inducing cell apoptosis. This information and the analytical methodology used to acquire it may form the basis for future ecological risk assessments on DP and related xenobiotics in aquatic animals. [ABSTRACT FROM AUTHOR]

A novel and simple scheme to generate Ultra-wideband (UWB) doublet signal with tunable notch band based on a tunable delay-line filter is presented. The first-order differentiation is realized by a dual-drive Mach–Zehnder modulator (DD-MZM), which differentiates the Gaussian pulses to the monocycle pulses. Subsequently, the UWB monocycle pulses are transmitted to an optical delay-line filter implemented by a balanced photo-detector and a tunable delay line for both differentiation and photodetection. Consequently, the desired UWB doublet signal can be obtained with a 10-dB bandwidth of 8.75 GHz. Besides, the polarity reversibility of the generated doublet signal is demonstrated by changing the bias voltage of the DD-MZM. Moreover, the desired notch can be introduced in the generated frequency spectrum to eliminate the interference between the existing narrowband systems and the UWB systems. And the tunability of the band-notched position is implemented by simply adjusting the delay time of the delay-line filter. The feasibility of the presented scheme is investigated by mathematical models and simulations. [ABSTRACT FROM AUTHOR]

The techniques for data clustering have been frequently applied in machine learning and computer vision, data mining. Among of these methods the Gaussian mixture model (GMM) has received considerable attention due to its flexibility, intuitiveness and ease of use. However, ignoring the non-Gaussian distribution, heavy computing burden for high dimension data, and the manifold structure of the data depress the performance of GMM. To overcome these limits, we propose the generalized Dirichlet mixture model with Laplacian regularization for clustering. The generalized Dirichle mixture model can fit both Gaussian and non-Gaussian type data, which is superior to the Gaussian mixture model. Based on the assumption that two data points are likely to be generated from the same Dirichlet component if they are sufficiently close on the manifold, we build a nearest neighbor graph to model the manifold structure and incorporate the manifold structure in a log-likelihood function of the Dirichlet mixture model as a regularization term. During the iteration, we employ the property of generalized Dirichle distribution to reduce the computation burden that decreases computation complexity. Extensive experimental results on four challenging databases demonstrate that the proposed algorithm performs favorably against the previous methods. [ABSTRACT FROM AUTHOR]

Groundwater in many parts of the world is contaminated with arsenic and nitrate. To date no technology is available that canin situremediate arsenic and nitrate pollution of groundwater using one single bacterial species. In this study, a novel anaerobic nitrate-dependent Fe(II)-oxidizing bacterium,Clostridiumsp. strain PXL2, was isolated from anoxic activated sludge. The strain PXL2 could efficiently oxidize Fe(II) associated with the reduction of nitrate. Scanning Electron Microscope (SEM), X-ray diffraction (XRD) and Fourier Transform Infrared Spectrometry (FTIR) analysis showed that strain PXL2 formed nanosize and poorly crystalline Fe(III) oxides which encrusted the cells, with the viability and function of the cells might being inhibited by the encrustation of Fe(III) oxides. It was found that strain PXL2 was an excellent candidate microbe for bioremediation of nitrate and arsenic pollution. It could effectively and simultaneously remove As(III) and nitrate from water due to its Fe(II) oxidation and denitrtification activity. 40.6–100% of NO3−was removed from an initial concentration of 12.3 mM. High concentrations of As(III) decreased nitrate removal. With initial concentrations of 10 μM, 65 μM and 125 μM As(III), 100% of As(III) was removed in a 20 d treatment. Arsenic was removed by adsorption to the biogenic Fe(III) oxides but not by adsorption to the cells. Strain PXL2 was also able to oxidize As(III) to less mobile and less toxic As(V) and this may significantly enhance the performance of bioremediation of arsenic pollution. Anaerobic nitrate-dependent Fe(II)-oxidizing species, such as strain PXL2, has great application potential forin situremediation of nitrate and metal(loid)s polluted groundwater with advantages of high efficiency and low cost. [ABSTRACT FROM AUTHOR]

Anaerobic Fe(II) Oxidizing Denitrifiers (AFODN), a type of newly found Fe(II)-oxidizing bacteria, play an important role in iron and nitrogen cycling. In the present study, a novel AFODN strain PXL1 was isolated from anaerobic activated sludge. Phylogenetic analysis of 16S rRNA gene sequence revealed similarity between this strain andCitrobactor freundii. The strain reduced 30% of nitrate and oxidized 85% of Fe(II) over 72 h with an initial Fe(II) concentration of 3.4 mM and nitrate concentration of 9.5 mM. Oxidation of iron was dependent on the reduction of nitrate to nitrite in the absence of other electron donors or acceptors. Nitrate reduction and Fe(II) oxidation followed first-order reaction kinetics. Iron oxides accumulated in the culture were analyzed by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) spectroscopy and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS). The strain recovered deposited oxidized Fe in the form of amorphous Fe oxides. [ABSTRACT FROM AUTHOR]

The enantioselectivity of chiral macrocyclic polyamides 1 – 3 derived from L-/D-tartaric acid was investigated by using 1 H NMR. All the macrocycles exhibited certain chiral recognition towards the enantiomers of the racemic carboxylic acids we had chosen. As a chiral solvating agent, the compound 3 has the excellent enantiomeric discriminating ability for mandelic acids and its derivatives, containing an α-OH at the chiral carbon, while the compound 2 has the best enantioselectivity towards dibenzoyltartaric acid. The molar ratio and the association constants of the compound 3 with each of the enantiomers of some guest molecules were determined by using the Job's plots and a nonlinear leastsquares fitting method, respectively. The effect of the structure of the hosts or guests on the enantioselectivity of the compound 1 – 3 has been explored. [ABSTRACT FROM AUTHOR]

A short and convenient synthesis for four novel chiral L-proline derived macrocyclic dioxopolyamines of C2 symmetry, by condensation of appropriate diester intermediates and polyamines, is reported. These macrocyclic dioxopolyamines may be applied as chiral solvating agents for enantiomeric recognition, and the work also provided a simple and convenient way for the synthesis of the diester intermediates. [ABSTRACT FROM AUTHOR]

Natural graphite was coated with different concentrations of phenolic resin and methane solution. To obtain modified graphite, the coated natural graphite was further carbonized at a temperature of 1000°C for 1 h under a N 2 stream after removing the solvent of methane. The surface morphology and microstructure of modified graphite were investigated with scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The computer-controlled constant-current cycler investigated charge and discharge performances. Results showed that the phenolic resin carbon with disordered structure formed on the surface of graphite could protect the graphite from exfoliation and improve its cyclic performances successfully. The reversible capacity and coulombic efficiencies of modified graphite were higher than that of natural graphite during charge and discharge cycling tests at a rate of 50 mA g -1 . It is confirmed that modified graphite has an advantage for an application of high power density lithium ion battery. [ABSTRACT FROM AUTHOR]

QiheCarassius auratusis the territorialCarassius auratus, which is known as for its limited distribute in Qihe River (mainly distributed in Henan province, China), this species is natural triploid in China. In this study, the complete mitochondrial genome sequence ofCarassius auratusin Qihe River has been obtained with PCR. The gene composition and arrangement of mitochondrial genome sequence of this species are similar to most of other vertebrates’, which contains 22 tRNA genes, 13 protein-coding genes, 2 rRNA genes, and a non-coding control region with total length of 16,580 bp. Most of genes are encoded on Heavy-Strand (H-strand), exclude eight tRNA andND6genes, which are encoded on Light-Strand (L-strand). The bias of G and C has been found in different regions/genes and different statistic results. The complete mitochondrial genome sequence of this species would contribute to better understand population genetics, conservation, and the evolution of natural triploid. [ABSTRACT FROM AUTHOR]

AbstractSelenium (Se) is an essential micronutrient for humans and animals and is a powerful antioxidant that can promote reproductive and immune functions. The purpose of this study was to evaluate the effects of supplemental dietary selenium-enriched yeast (SeY) on egg quality, gut morphology and microflora in laying hens. In total, 100 HY-Line Brown laying hens (45-week old) were randomly allocated to two groups with 10 replicates and fed either a basal diet (without Se supplementation) or a basal diet containing 0.2 mg/kg Se in the form of SeY for 8 weeks. The Se supplementation did not have a significant effect on egg quality and intestinal morphology of laying hens. Based on the 16S rRNA sequencing, SeY dietary supplementation effectively modulated the cecal microbiota structure. An alpha diversity analysis demonstrated that birds fed 100 mg/kg SeY had a higher cecal bacterial diversity. SeY dietary addition elevated Erysipelotrichia (class), Lachnospiraceae (family), Erysipelotrichaceae (family) and Ruminococcus_torques_group (genus; p < .05). Analysis of microbial community-level phenotypes revealed that SeY supplementation decreased the microorganism abundance of facultatively anaerobic and potentially pathogenic phenotypes. Overall, SeY supplementation cannot significantly improve intestinal morphology; however, it modulated the composition of cecal microbiota toward a healthier gut. [ABSTRACT FROM AUTHOR]