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The objective of this paper was to investigate the transepithelial transport of two novel corn gluten-derived antioxidant peptides, YFCLT and GLLLPH, using Caco-2 cell monolayers. Results showed that both of YFCLT and GLLLPH could transport in intact form across Caco-2 cell monolayers with apparent permeability coefficient (P app ) values of (1.10±0.16)×10 -7 cm/s and (1.98±0.23)×10 -7 cm/s, respectively. However, it was found that the two peptides were susceptible and easily hydrolyzed by brush border membrane peptidases. In the presence of diprotin A, an inhibitor of dipeptidyl peptidase IV (DPPIV), the hydrolysis of YFCLT and GLLLPH decreased and their permeabilities increased significantly compared to control group (P<0.05). The results of transport routes revealed that Gly-Sar, a peptide transporter 1 (PepT1) substrate, had little effects on the transepithelial permeability (P>0.05), suggesting that the transport of YFCLT and GLLLPH across Caco-2 cell monolayers was not mediated by PepT1. However, it was found that cytochalasin d, a tight junctions (TJs) disruptor, increased the permeability significantly (P<0.05). While wortmannin, a transcytosis inhibitor, and sodium azide, an ATP synthesis inhibitor, both decreased the permeability significantly (P<0.05). It indicated that the TJs-mediated paracellular pathway and energy-dependent transcytosis were involved in the transport of YFCLT and GLLLPH across Caco-2 cell monolayers., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Alzheimer's disease (AD) is a global health issue affecting millions of elderly people worldwide. The aim of the present study was to identify novel anti-AD peptides isolated from albumin. Anti-AD activities of the peptides were evaluated via inhibitory activities on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Furthermore, the potential molecular mechanisms of the KLPGF/AChE were investigated by CDOCKER of Discovery studio 2017. The results revealed that peptide KLPGF could effectively inhibit AChE with an inhibition rate of 61.23% at a concentration of 50 μg mL -1 . In addition, the peptide KLPGF came in contact with acylation sites and peripheral anion sites of AChE. The present study demonstrates that the peptide KLPGF could become a potential functional food intervention in AD.

The objective of this paper was to investigate the effects of terminal amino acids on the transport of oligopeptides across the Caco-2 cell monolayer. Ala-based tetra- and pentapeptides were designed, and the N- or C-terminal amino acid residues were replaced by different amino acids. The results showed that the oligopeptides had a wide range of transport permeability across the Caco-2 cell monolayer and could be divided into four categories: non-/poor permeability, low permeability, intermediate permeability, and good permeability. Tetrapeptides with N-terminal Leu, Pro, Ile, Cys, Met, and Val or C-terminal Val showed the highest permeability, with apparent permeability coefficient (P app ) values over 10 × 10 -6 cm/s (p < 0.05), suggesting that nonpolar hydrophobic aliphatic amino acids or polar sulfur-containing amino acids were the best for the transport of tetrapeptides. Pentapeptides with N- or C-terminal Tyr also showed high permeability levels, with P app values of about 10 × 10 -6 cm/s. The amino acids Glu, Asn, and Thr at the N terminus or Lys, Asp, and Arg at the C terminus were also beneficial for the transport of tetra- and pentapeptides, with P app values ranging from 1 × 10 -6 to 10 × 10 -6 cm/s. In addition, peptides with amino acids replaced at the N terminus generally showed higher permeability than those with amino acids replaced at the C terminus (p < 0.05), suggesting that N-terminal amino acids were more important for the transport of oligopeptides across the Caco-2 cell monolayer.

Effects of drought stress on photosynthetic characteristics, water status, physiological and biochemical indexes were studied in five arid area plants in northwest China, including Potentilla fruticosa, Lycium ruthenicum, Caryopteris mongholica, Caragana korshinskii and Hedysarum scoparium, using pot experiments. The results showed that with the prolongation of drought stress, the water conservation capacity of leaves totally increased in above five plants, the leaf relative water content rose first and then fell, and the relative chlorophyll content and chlorophyll fluorescence parameters decreased to some extent. Overall, the photosynthetic system of H. scoparium and L. ruthenicum least affected by the stress, and P. fruticosa suffered with the most serious damage. The electric conductivity and malondialdehyde (MDA) content of P. fruticosa firstly decreased and then sharply increased, while superoxide dismutase (SOD) and peroxidase (POD) activities firstly increased and then dramatically decreased. With the decrease of soil water content, the electric conductivity rose firstly and then fell in the other four plants,the change of MDA content rose first and then fell, or fell first and then rose, and the activities of SOD and POD almost displayed upward trend. Especially, SOD activity of C. mongholica and POD activity of H. scoparium had the biggest increment among the five plants after 28 days of drought stress, increasing by 1.1 and 13.1 times respectively, compared with before processing. Additionally, there was significant variance in the accumulation of organic solutes among the five plants during the drought stress treatment. The accumulation of soluble sugar and free proline was the most in P. fruticosa, increasing by 1.1 and 22.4 times respectively, after 28 days of drought treatment. H. sco-parium accumulated the most soluble protein, increasing by 1.0 times after 28 days of drought treatment. The result of membership function method showed that the drought tolerance decreased in order of H. scoparium ＞ L. ruthenicum ＞ C. korshinskii ＞ C. mongholica ＞ P. fruticosa. The research revealed that all five plants could make positive response to drought stress through improving the activity of antioxidant enzymes and accumulating organic solutes, which could help to reduce cell damage. P. fruticos was most sensitive to water deficit in the five plants, and the degree of drought had exceeded its own regulated capacity threshold during the experiment.

The striatum is an input channel of the basal ganglia and is well known to be involved in reward-based decision making and learning. At the macroscopic level, the striatum has been postulated to contain parallel functional modules, each of which includes neurons that perform similar computations to support selection of appropriate actions for different task contexts. At the single-neuron level, however, recent studies in monkeys and rodents have revealed heterogeneity in neuronal activity even within restricted modules of the striatum. Looking for generality in the complex striatal activity patterns, here we briefly survey several types of striatal activity, focusing on their usefulness for mediating behaviors. In particular, we focus on two types of behavioral tasks: reward-based tasks that use salient sensory cues and manipulate outcomes associated with the cues; and perceptual decision tasks that manipulate the quality of noisy sensory cues and associate all correct decisions with the same outcome. Guided by previous insights on the modular organization and general selection-related functions of the basal ganglia, we relate striatal activity patterns on these tasks to two types of computations: implementation of selection and evaluation. We suggest that a parsing with the selection/evaluation categories encourages a focus on the functional commonalities revealed by studies with different animal models and behavioral tasks, instead of a focus on aspects of striatal activity that may be specific to a particular task setting. We then highlight several questions in the selection-evaluation framework for future explorations.

The objective of this study was to investigate the intracellular reactive oxygen species (ROS) scavenging activities and antioxidant enzyme regulating capacities of corn gluten peptide fractions (CPFs) in HepG2 cells. A cellular antioxidant activity (CAA) assay was used to assess their antioxidant activities and revealed that both CPF1 (molecular weight <1kDa) and CPF2 (molecular weight between 1 and 3kDa) exhibited high cellular antioxidant activities with EC 50 values of 2.85±0.19mg/mL and 5.05±0.32mg/mL, respectively. Both CPFs also exhibited cytoprotective effects and intracellular ROS scavenging activities in HepG2 cells subjected to oxidative stress by oxidation with H 2 O 2 . In addition, at concentrations of 2.50mg/mL, the CPFs increased the activity levels of superoxide dismutase (SOD), catalase (CAT), and glutathione reductase (GR), as well as the total glutathione (GSH) levels in oxidized HepG2 cells (from 86.54% to 114.14% (CPF1) or 109.72% (CPF2) for SOD activity; from 71.91% to 107.64% (CPF1) or 106.50% (CPF2) for CAT activity; from 70.52% to 103.01% (CPF1) or 104.10% (CPF2) for GR activity; and from 81.39% to 114.00% (CPF1) or 108.82% (CPF2) for total GSH levels). These results suggested that both CPF1 and CPF2 exhibited positive effects on the activities of the intracellular antioxidant enzymes SOD, CAT and GR, as well as on the total GSH levels in HepG2 cells under conditions of oxidative stress. Furthermore, size exclusion gel chromatography and MALDI-TOF/TOF mass spectrometry revealed that the molecular weights of the antioxidant peptides in CPF1 were between 500Da to 900Da, and a novel antioxidant peptide consisting of GLLLPH (Gly-Leu-Leu-Leu-Pro-His) was identified in CPF1., (Copyright © 2016. Published by Elsevier Ltd.)

In this paper, an experimental velocity database of a bacterial collective motion, e.g., Bacillus subtilis, in turbulent phase with volume filling fraction 84% provided by Professor Goldstein at Cambridge University (UK), was analyzed to emphasize the scaling behavior of this active turbulence system. This was accomplished by performing a Hilbert-based methodology analysis to retrieve the scaling property without the β-limitation. A dual-power-law behavior separated by the viscosity scale ℓ&#95;{ν} was observed for the qth-order Hilbert moment L&#95;{q}(k). This dual-power-law belongs to an inverse-cascade since the scaling range is above the injection scale R, e.g., the bacterial body length. The measured scaling exponents ζ(q) of both the small-scale (k>k&#95;{ν}) and large-scale (k

Phosphine-catalyzed regiodivergent enantioselective C-2- and C-4-selective γ-additions of oxazolones to 2,3-butadienoates have been developed. The C-4-selective γ-addition of oxazolones occurred in a highly enantioselective manner when 2-aryl-4-alkyloxazol-5-(4H)-ones were employed as pronucleophiles. With the employment of 2-alkyl-4-aryloxazol-5-(4H)-ones as the donor, C-2-selective γ-addition of oxazolones took place in a highly enantioselective manner. The C-4-selective adducts provided rapid access to optically enriched α,α-disubstituted α-amino acid derivatives, and the C-2-selective products led to facile synthesis of chiral N,O-acetals and γ-lactols. Theoretical studies via DFT calculations suggested that the origin of the observed regioselectivity was due to the distortion energy that resulted from the interaction between the nucleophilic oxazolide and the electrophilic phosphonium intermediate.

Three novel egg white-derived peptides were demonstrated to display in vitro activities against the angiotensin converting enzyme (ACE). A further study was conducted to assess their anxiolytic-like effects upon spontaneously hypertensive rats (SHRs) after an oral administration of the peptides, which showed the same behavioral performance as that using an elevated plus maze (EPM). In the EPM experiment, the behavioral effects of peptides TNGIIR, RVPSL, and QIGLF were investigated at doses ranging from 5 to 50 mg kg(-1), with records of the number of entries by the rats into the open arms, the time the rats spent in the open arms, and the total amount of entries into the open + closed arms. The results showed that the peptides TNGIIR and RVPSL, in a range of 5-50 mg kg(-1), exerted an anxiolytic effect on the SHRs. These results suggested that the egg white derived peptides TNGIIR and RVPSL could be considered as possible functional food or food ingredients due to their in vivo anti-stress and anti-anxiety effects on the SHRs.

The objective of this study was to investigate the digestion and absorption of egg white-derived angiotensin I-converting enzyme (ACE)-inhibitory peptide TNGIIR in human intestinal Caco-2 cell monolayers. Results showed that the digestion of TNGIIR to simulated gastrointestinal enzymes and brush border membrane peptidases were 5.87% ± 1.92% and 17.17% ± 0.64%, respectively (p < 0.05). The apparent permeability coefficients (P(app)) of TNGIIR from the apical to basolateral side in Caco-2 cell monolayers was determined to be (4.92 ± 0.40) × 10(-6) cm/s, indicating that TNGIIR can transport across Caco-2 cell monolayers in intact form. In addition, only cytochalasin D, a disruptor of tight junctions (TJs), changed TNGIIR transport rate significantly (p < 0.05), suggesting that the main transport route for TNGIIR across Caco-2 cell monolayers was paracellular pathway via TJs.

Phosphine-catalyzed highly enantioselective γ-additions of 5 H -thiazol-4-ones and 5 H -oxazol-4-ones to allenoates have been developed for the first time. With the employment of amino-acid derived bifunctional phosphines, a wide range of substituted 5 H -thiazol-4-one and 5 H -oxazol-4-one derivatives bearing heteroatom (S or O)-containing tertiary chiral centers were constructed in high yields and excellent enantioselectivities. The reported method provides facile access to enantioenriched tertiary thioethers/alcohols. The mechanism of the γ-addition reaction was investigated by performing DFT calculations, and the hydrogen bonding interactions between the Brønsted acid moiety of the phosphine catalysts and the "C[double bond, length as m-dash]O" unit of the donor molecules were shown to be crucial in asymmetric induction., (This journal is © The Royal Society of Chemistry 2015.)

Fertilization affects bacterial communities and element biogeochemical cycling in flooded paddy soils and the effect might differ among soil types. In this study, five paddy soils from Southern China were subjected to urea addition to explore impacts of fertilization on nitrogen oxide (N2O) emission and bacterial community composition under the flooding condition. 16S rRNA gene-based illumina sequencing showed no obvious shifts in bacterial community composition of five soils after urea addition. However, some genera were affected by fertilization addition and the influenced genera varied among soils. During the late period (day 8-19) of flooding incubation without urea addition, N2O emission rates were elevated for all soils. However, urea effects on N2O emission were different among flooded soils. For soils where nirS and nirK gene abundances increased with urea addition, N2O emission was significantly increased compared to control treatment. Redundancy analysis showed that dissolved organic carbon, ammonium (NH4 (+)), ferrous iron (Fe(2+)) and nitrate (NO3 (-)) in pore water explained 33.4% of the variation in soil bacterial community composition, implying that urea regimes influenced the relative abundance of some bacterial populations possibly by regulating soil characteristics and then influencing N2O emission. These results provided insights into soil type-dependent effect of fertilization on the overall bacterial communities and nitrogen oxide emission in flooded paddy soils., (© FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Iron reduction is an important biogeochemical process in paddy soils, yet little is known about the microbial coupling between nitrogen and iron reduction. Here, we investigated the shift of acetate-metabolizing iron-reducers under long-term nitrogen fertilization using (13)C-acetate-based ribosomal RNA (rRNA)-stable isotope probing (SIP) and pyrosequencing in an incubation experiment, and the shift of putative iron-reducers in original field samples were investigated by 16S rRNA gene-based pyrosequencing. During SIP incubations, in the presence of iron(III) oxyhydroxides, more iron(II) formation and less methane production were detected in nitrogen-fertilized (N) compared with non-fertilized (NF) soil. In (13)C-rRNA from microcosms amended with ferrihydrite (FER), Geobacter spp. were the important active iron-reducers in both soils, and labeled to a greater extent in N (31% of the bacterial classified sequences) than NF soils (11%). Pyrosequencing of the total 16S rRNA transcripts from microcosms at the whole community level further revealed hitherto unknown metabolisms of potential FER reduction by microorganisms including Pseudomonas and Solibacillus spp. in N soil, Dechloromonas, Clostridium, Bacillus and Solibacillus spp. in NF soil. Goethite (GOE) amendment stimulated Geobacter spp. to a lesser extent in both soils compared with FER treatment. Pseudomonas spp. in the N soil and Clostridium spp. in the NF soil may also be involved in GOE reduction. Pyrosequencing results from field samples showed that Geobacter spp. were the most abundant putative iron-reducers in both soils, and significantly stimulated by long-term nitrogen fertilization. Overall, for the first time, we demonstrate that long-term nitrogen fertilization promotes iron(III) reduction and modulates iron-reducing bacterial community in paddy soils.

In the present study, the carboxyl content of oxidized starch was determined by FTIR spectroscopy. Standard curve was drawn in which the ordinate was carboxyl content determined by national standard method with the ratio of carbonyl absorbance to the key of C-H absorbance in FTIR spectroscopy as the abscissa. The ratio of absorbance of unknown oxidized starch tested by FTIR spectroscopy was obtained, The carboxyl content was calculated by standard curve, and then compared with the carboxyl content determined by national standard method, and the deviation is between 2% and 4%. In order to improve the accuracy of the experiment, standard sample was selected to draw standard curve to better ensure that the carboxyl content of the unknown oxidized starch is in the range of standard curve calculation limit, and deviates from the limit of standard curve. Compared with the carboxyl content determined by national standard method, testing with FTIR spectroscopy is simple, easy to operate, and of high efficiency and better accuracy. So, it is significant to forecast the carboxyl content of oxidized starch by FTIR spectroscopy.

Epidermal growth factor receptor (EGFR) signaling is an important pathway that is not only involved in the determination of cellular development, but also has significant roles in tumor development and progression. The study aims to examine the expression of EGFR signaling pathway-related proteins (EGFR, c-Fos, and c-erb-B2) in esophageal squamous cell carcinoma and to investigate their relationships with clinical significance. Sixty esophageal squamous carcinoma specimens obtained by fiber esophagoscope were subjected to two-step immunohistochemistry to test the expression of EGFR, c-Fos, and c-erb-B2. EGFR expression was observed in 73.3% of tumors (44/60); positive EGFR expression was significantly correlated with tumor-node-metastasis (TNM) staging, lymph node metastasis, and distant metastasis (P < 0.05). c-Fos expression was found in 85% (51/60) of tumors, and its expression was significantly related to tumor depth and TNM staging (P < 0.05). c-erb-B2 expression was 75% (45/60) in esophageal squamous cell carcinoma (ESCC) specimens, and positive-erb-B2 expression had a significant association with the depth of tumor invasion (P < 0.05). c-Fos expression was significantly and positively correlated with c-erb-B2 (P < 0.05). Overexpression of EGFR, c-Fos, and c-erb-B2 was associated with tumor progression and development. EGFR and c-Fos expression can predict the tumor stage. c-Fos and c-erb-B2 expression can be used to determine the depth of tumor invasion and can also act as a combined prognostic indicator in ESCC.

The long-standing doctrine regarding the functional organization of the direct dorsal column (DDC) pathway is the "somatotopic map" model, which suggests that somatosensory afferents are primarily organized by receptive field instead of modality. Using modality-specific genetic tracing, here we show that ascending mechanosensory and proprioceptive axons, two main types of the DDC afferents, are largely segregated into a medial-lateral pattern in the mouse dorsal column and medulla. In addition, we found that this modality-based organization is likely to be conserved in other mammalian species, including human. Furthermore, we identified key morphological differences between these two types of afferents, which explains how modality segregation is formed and why a rough "somatotopic map" was previously detected. Collectively, our results establish a new functional organization model for the mammalian direct dorsal column pathway and provide insight into how somatotopic and modality-based organization coexist in the central somatosensory pathway.

Objective: To study the effects of environmental multi-media lead pollution on blood lead and sex hormone levels among lead exposed males engaged in E-waste dismantling, and the correlation between confounding factors and sex hormone levels., Methods: An E-waste dismantling area in Taizhou of Zhejiang Province was selected as the research site. One hundred and fifty two samples were collected from the groundwater, soil, rice, corn, chicken, and pork in the dismantling area. The effects of the multi-media lead pollution on the male blood lead and sex hormone levels of FSH, LH, and T, as well as the correlation with confounding factors, were studied., Results: The blood lead concentrations in the males aged under 31, from 31 to 45 and from 46 to 60 were 98.55, 100.23, and 101.45 μg/L, respectively. Of all the environmental media lead exposures, the groundwater, rice and soil were main contributing factors to the lead accumulation in humans. FSH and LH levels increased with the age while the T levels decreased with the age instead. There was a significant correlation between the FSH and LH levels and wearing masks., Conclusion: There was correlation between the FSH, LH, and T levels, and the mean values of lead concentrations in environmental media, and the sex hormone levels were correlated with the confounding factor of wearing masks., (Copyright © 2013 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.)

Psychometric functions are often interpreted in the context of Signal Detection Theory, which emphasizes a distinction between sensory processing and non-sensory decision rules in the brain. This framework has helped to relate perceptual sensitivity to the "neurometric" sensitivity of sensory-driven neural activity. However, perceptual sensitivity, as interpreted via Signal Detection Theory, is based on not just how the brain represents relevant sensory information, but also how that information is read out to form the decision variable to which the decision rule is applied. Here we discuss recent advances in our understanding of this readout process and describe its effects on the psychometric function. In particular, we show that particular aspects of the readout process can have specific, identifiable effects on the threshold, slope, upper asymptote, time dependence, and choice dependence of psychometric functions. To illustrate these points, we emphasize studies of perceptual learning that have identified changes in the readout process that can lead to changes in these aspects of the psychometric function. We also discuss methods that have been used to distinguish contributions of the sensory representation versus its readout to psychophysical performance., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Based on the boundary elements of system risk assessment, the regional groundwater pollution risk assessment index system was preliminarily established, which included: regional groundwater specific vulnerability assessment, the regional pollution sources characteristics assessment and the health risk assessment of regional featured pollutants. The three sub-evaluation systems were coupled with the multi-index comprehensive method, the risk was characterized with the Spatial Analysis of ArcMap, and a new method to evaluate regional groundwater pollution risk that suitable for different parts of natural conditions, different types of pollution was established. Take Changzhou as an example, the risk of shallow groundwater pollution was studied with the new method, and found that the vulnerability index of groundwater in Changzhou is high and distributes unevenly; The distribution of pollution sources is concentrated and has a great impact on groundwater pollution risks; Influenced by the pollutants and pollution sources, the values of health risks are high in the urban area of Changzhou. The pollution risk of shallow groundwater is high and distributes unevenly, and distributes in the north of the line of Anjia-Xuejia-Zhenglu, the center of the city and the southeast, where the human activities are more intense and the pollution sources are intensive.

Perceptual decision making requires a complex set of computations to implement, evaluate, and adjust the conversion of sensory input into a categorical judgment. Little is known about how the specific underlying computations are distributed across and within different brain regions. Using a reaction-time (RT) motion direction-discrimination task, we show that a unique combination of decision-related signals is represented in monkey frontal eye field (FEF). Some responses were modulated by choice, motion strength, and RT, consistent with a temporal accumulation of sensory evidence. These responses converged to a threshold level prior to behavioral responses, reflecting decision commitment. Other responses continued to be modulated by motion strength even after decision commitment, possibly providing a memory trace to help evaluate and adjust the decision process with respect to rewarding outcomes. Both response types were encoded by FEF neurons with both narrow- and broad-spike waveforms, presumably corresponding to inhibitory interneurons and excitatory pyramidal neurons, respectively, and with diverse visual, visuomotor, and motor properties, albeit with different frequencies. Thus, neurons throughout FEF appear to make multiple contributions to decision making that only partially overlap with contributions from other brain regions. These results help to constrain how networks of brain regions interact to generate perceptual decisions.

On the basis of site investigation and data collection of a certain hazardous waste landfill, the groundwater flow and solute transport coupled models were established by applying Visual Modflow software, which was used to conduct a numerical simulation that forecast the transport process of Cr6+ in groundwater and the effects of three control measures (ground-harden, leakage-proof barriers and drainage ditches) of contaminants transport after leachate leakage happened in impermeable layer of the landfill. The results show that the contamination plume of Cr6+ transports with groundwater flow direction, the contamination rang would reach the pool's boundary in 10 years, and the distance of contamination transport is 1 450 m. But the diffusion range of contamination plume would not be obviously expanded between 10 and 20 years. While the ground is hardened, the contamination plume would not reach the pool's boundary in 20 years. When the leakage-proof barrier is set in the bottom of water table aquifer, the concentration of Cr6+ is higher than that the leakage-proof barrier is unset, but the result is just opposite when setting the leakage-proof barrier in the bottom of underlying aquifer. The range of contamination plume is effectively controlled by setting drainage ditches that water discharge is 2 642 m3 x d(-1), which makes the monitoring wells would not be contaminated in 20 years. Moreover, combining the ground-harden with drainage ditches can get the best effect in controlling contaminants diffusion, and meanwhile, the drainage ditches' daily discharge is reduced to 1 878 m3 x d(-1). Therefore, it is suggested that the control measure combining the ground-harden with drainage ditches should apply to prevent contamination diffusion in groundwater when leachate leakage have happened in impermeable layer of the landfill.

ZPF(zeoliteartificial pillared by alpha-FeOOH) which prepared in the laboratory and characterized by FTIR and XRD was used as catalyst, and was tested for its activity in catalytic H2O2, of 2,4-DNT, which is persistent and difficult to be degraded in groundwater. The degradation of 2,4-DNT was examined at different pHs in the reduction, catalytic oxidation and combination technology of reduction-catalytic oxidation reaction systems. Moreover, the removal effect of 2,4-DNT was compared by these three approaches and the catalytic oxidation mechanism was analyzed. The results demonstrated that the removal effect of 2,4-DNT reduced to 2,4-DAT was up to 96.6% in 120 min at pH = 5, which was 1.2, 2.0 times of the rate at pH 7, pH 9 respectively. The catalytic effect was various at different pHs and more significant when the pH close to the zero point of charge of alpha-FeOOH. The order of removal effect of 2,4-DNT at different pHs was pH = 7 > pH = 9 > pH = 5. Compared to single reduction or catalytic oxidation, the removal effect of combination technology was 57.4%, which was evidently improved on the base of 2,4-DNT reduced to 2,4-DAT. The degradation of 2,4-DNT in the presence of ZPF/H2O2 follows a first-order kinetic model and the k(obs) was 0.002 7 min(-1). Due to the concentration of dissolved Fe ion was far less than 0.07 mmol/L, the mechanism was heterogeneous Fenton reaction acting on the surface of the catalyst. Therefore the combination technology was superior to the single treatment of reduction or catalytic oxidation.

In order to further understand the mechanisms of microbial immobilization of phosphorous (P) in highly weathered red soil with organic amendment, an incubation test was conducted to investigate the roles of microbial functional groups in the transformation of P in 0.2-2 mm soil aggregates. Throughout the 90-day incubation period, amendment with rice straw induced a substantial increase in the amounts of microbial biomass C and P, Olsen-P, and organic P in the aggregates. Comparing with rice straw amendment alone, the amendment with rice straw plus fungal inhibitor actidione decreased the amount of microbial biomass C in the aggregates by 10.5%-31.8% in the first 30 days. Such a decrement was significantly larger than that (6.8%-11.6%) in the treatment amended with rice straw plus bacterial inhibitors tetracycline and streptomycin sulphate (P<0.01). After the first 30 days, the microbial biomass C remained constant. In the first 20 days, the amount of microbial biomass P in the aggregates was 10.0%-28.8% higher in the treatment amended with bacterial inhibitors than in the treatment amended with fungal inhibitor (P<0.01). All the results suggested that that both the fungal and the bacterial groups were involved in the microbial immobilization of P in the soil aggregates, and the fungal group played a relatively larger role.

Song learning in oscine birds relies on a circuit known as the "anterior forebrain pathway," which includes a specialized region of the avian basal ganglia. This region, area X, is embedded within a telencephalic structure considered homologous to the striatum, the input structure of the mammalian basal ganglia. Area X has many features in common with the mammalian striatum, yet has distinctive traits, including largely aspiny projection neurons that directly innervate the thalamus and a cell type that physiologically resembles neurons recorded in the mammalian globus pallidus. We have proposed that area X is a mixture of striatum and globus pallidus and has the same functional organization as circuits in the mammalian basal ganglia. Using electrophysiological and anatomical approaches, we found that area X contains a functional analog of the "direct" striatopallidothalamic pathway of mammals: axons of the striatal spiny neurons make close contacts on the somata and dendrites of pallidal cells. A subset of pallidal neurons project directly to the thalamus. Surprisingly, we found evidence that many pallidal cells may not project to the thalamus, but rather participate in a functional analog of the mammalian "indirect" pathway, which may oppose the effects of the direct pathway. Our results deepen our understanding of how information flows through area X and provide more support for the notion that song learning in oscines employs physiological mechanisms similar to basal ganglia-dependent forms of motor learning in mammals., (Copyright 2005 Wiley-Liss, Inc.)