Showing papers by "Zhejiang Gongshang University published in 2012"

Atmospheric reactive nitrogen in China: sources, recent trends, and damage costs.

Abstract: Human activities have intensely altered the global nitrogen cycle and produced nitrogenous gases of environmental significance, especially in China where the most serious atmospheric nitrogen pollution worldwide exists. We present a comprehensive assessment of ammonia (NH3), nitrogen oxides (NOx), and nitrous oxide (N2O) emissions in China based on a full cycle analysis. Total reactive nitrogen (Nr) emission more than doubled over the past three decades, during which the trend of increase slowed for NH3 emissions after 2000, while the trend of increase continued to accelerate for NOx and N2O emissions. Several hotspots were identified, and their Nr emissions were about 10 times higher than others. Agricultural sources take 95% of total NH3 emission; fossil fuel combustion accounts for 96% of total NOx emission; agricultural (51%) and natural sources (forest and surface water, 39%) both contribute to the N2O emission in China. Total atmospheric Nr emissions related health damage in 2008 in China reached US...

Expression of fatty acid synthesis genes and fatty acid accumulation in haematococcus pluvialis under different stressors.

Abstract: Background Biofuel has been the focus of intensive global research over the past few years. The development of 4th generation biofuel production (algae-to-biofuels) based on metabolic engineering of algae is still in its infancy, one of the main barriers is our lacking of understanding of microalgal growth, metabolism and biofuel production. Although fatty acid (FA) biosynthesis pathway genes have been all cloned and biosynthesis pathway was built up in some higher plants, the molecular mechanism for its regulation in microalgae is far away from elucidation.

Direct Discovery of High Utility Itemsets without Candidate Generation

Abstract: Utility mining emerged recently to address the limitation of frequent itemset mining by introducing interestingness measures that reflect both the statistical significance and the user's expectation. Among utility mining problems, utility mining with the itemset share framework is a hard one as no anti-monotone property holds with the interestingness measure. The state-of-the-art works on this problem all employ a two-phase, candidate generation approach, which suffers from the scalability issue due to the huge number of candidates. This paper proposes a high utility itemset growth approach that works in a single phase without generating candidates. Our basic approach is to enumerate itemsets by prefix extensions, to prune search space by utility upper bounding, and to maintain original utility information in the mining process by a novel data structure. Such a data structure enables us to compute a tight bound for powerful pruning and to directly identify high utility itemsets in an efficient and scalable way. We further enhance the efficiency significantly by introducing recursive irrelevant item filtering with sparse data, and a lookahead strategy with dense data. Extensive experiments on sparse and dense, synthetic and real data suggest that our algorithm outperforms the state-of-the-art algorithms over one order of magnitude.

Design of iron chelators with therapeutic application

Abstract: Iron is essential for the proper functioning of all living cells, however it is toxic when present in excess. Thus, using iron chelators as therapeutic agents, namely chelation therapy, has received increasing attention. The objective of this review is to discuss the factors which should be considered when designing clinically useful iron chelators, to present the application of iron chelators in the treatment of iron overload associated with β-thalassaemia major and sickle cell anaemia, and to highlight the potential applications in the treatment of neurodegenerative disorders and microbial infection. This article reviews recent knowledge centred on these themes and indicates the growing importance of the concept of iron chelation in medicine.

Multiple-resource and multiple-depot emergency response problem considering secondary disasters

Abstract: Optimal allocation of emergency resources is a crucial content of emergency management. It is a key step in emergency rescue and assistance. Multiple resources and potential secondary disasters are often neglected in the existing methods, which desperately need to be improved. In this paper, we formulate the emergency resource allocation problem with constraints of multiple resources and possible secondary disasters, and model the multiple resources and multiple emergency response depots problem considering multiple secondary disasters by an integer mathematical programming. For the complexity, a heuristic algorithm is designed to efficiently solve it based on linear programming and network optimization. The algorithm modifies the solutions of the linear programming by setting a priority of preference for each location where the secondary disasters will take place with certain possibilities. The numerical simulation provides evidence for its effectiveness and efficiency. Our method and algorithm can also be implemented in the practical applications with large-scale scenario.

National assessment of coastal vulnerability to sea-level rise for the Chinese coast

Abstract: Sea-level rise as a result of climate change increases inundation and erosion, which are affected by a complex interplay of physical environmental parameters at the coast. China’s coast is vulnerable to accelerated sea-level rise and associated coastal flooding because of physical and socio-economical factors such as its low topography, highly developed economy, and highly dense population. To identify vulnerable sections of the coast, this paper presents a national assessment of the vulnerability of the Chinese coast using 8 physical variables: sea-level rise, coastal geomorphology, elevation, slope, shoreline erosion, land use, mean tide range, and mean wave height. A coastal vulnerability index was calculated by integrating the differentially weighted rank values of the 8 variables, based on which the coastline is segmented into 4 classes. The results show that 3% of the 18,000-km-long Chinese coast is very highly vulnerable, 29% is highly vulnerable, 58% is moderately vulnerable, and 10% is in the low-vulnerable class. Findings further reveal that large amounts of land and population will be vulnerable to inundation by coastal flooding from sea level rise and storm surge. Finally, some suggestions are presented for decision makers and other concerned stakeholders to develop appropriate coastal zone management and mitigation measures.

Effects of lactobacillus plantarum ZJ316 on pig growth and pork quality.

Abstract: Lactobacillus plantarum is a plant-associated bacterial species but it has also been found in human, mouse and porcine gastrointestinal tracts. It can ferment a broad spectrum of plant carbohydrates; it is tolerant of bile salts and low pH, and it has antagonistic potential against intestinal pathogens. However, experiments reporting the use of L. plantarum as a probiotic are limited. In this study, the effects of L. plantarum ZJ316 isolated from infant fecal samples on pig growth and pork quality were investigated. One hundred and fifty newly weaned pigs were selected randomly and divided into five groups. Group 1 was fed a diet supplemented with the antibiotic mequindox; Groups 2, 3 and 4 were fed a diet supplemented with L. plantarum and no antibiotic; and Group 5 was fed a mixture of mequindox and L. plantarum. After a 60 days initial treatment, samples were collected for evaluation. The results showed that, the L. plantarum ZJ316 has probiotic effects on pig growth and that these effects are dose dependent. The effects of a dose of 1 × 109 CFU/d were more pronounced than those of a dose of 5 × 109 CFU/d or 1 × 1010 CFU/d. In Group 2 (1 × 109 CFU/d), the diarrhea (p = 0.000) and mortality rates (p = 0.448) were lower than in antibiotic-treated pigs (Group 1), and the daily weight gain (p = 0.001) and food conversion ratios were better (p = 0.005). Improved pork quality was associated with Lactobacillus treatment. pH (45 min, p = 0.020), hardness (p = 0.000), stickiness (p = 0.044), chewiness (p = 0.000), gumminess (p = 0.000) and restoring force (p = 0.004) were all significantly improved in Lactobacillus-treated pigs (Group 2). Although we found that L. plantarum exerted probiotic effects on pig growth and pork quality, the mechanisms underlying its action require further study. Polymerase chain reaction-denaturing gradient gel electrophoresis results showed that the gut bacterial communities in Lactobacillus- and antibiotic-treated pigs were very similar and the quantity of L. plantarum ZJ316 was below the detection limits of DGGE-band sequencing. The concentration of short-chain fatty acids in Lactobacillus- and antibiotic-treated fecal samples were not significantly different (p = 0.086). However, the villus height of ilea (p = 0.003), jejuna (p = 0.000) and duodena (p = 0.036) were found to be significantly improved by Lactobacillus treatment. L. plantarum ZJ316 was found to have probiotic effects, improving pig growth and pork quality. The probiotic mechanism might not involve L. plantarum colonization and alteration of the gut bacterial community. Rather, it might be related to the inhibition of the growth of opportunistic pathogens and promotion of increased villus height.

Preservation of (−)-Epigallocatechin-3-gallate Antioxidant Properties Loaded in Heat Treated β-Lactoglobulin Nanoparticles

Abstract: (-)-Epigallocatechin-3-gallate (EGCG) was loaded in heat treated β-lactoglobulin (β-Lg) for the preservation of antioxidant activity. The effects of pH (2.5-7.0), the heating temperature of β-Lg (30-85 °C), the molar ratio of β-Lg to EGCG (1:2-1:32), and the β-Lg concentration (1-10 mg/mL) on the properties of β-Lg-EGCG complexes were studied. All four factors significantly influenced the particle size, the ζ-potential, and the entrapment efficiency of EGCG and EGCG loading in β-Lg particles. A stable and clear solution system could be obtained at pH 6.4-7.0. The highest protection of EGCG antioxidant activity was obtained with β-Lg heated at 85 °C and the molar ratio of 1:2 (β-Lg: EGCG). β-Lg-EGCG complexes were found to have the same secondary structure as native β-Lg.

Iron uptake system mediates nitrate-facilitated cadmium accumulation in tomato (Solanum lycopersicum) plants

Abstract: Nitrogen (N) management is a promising agronomic strategy to minimize cadmium (Cd) contamination in crops. However, it is unclear how N affects Cd uptake by plants. Wild-type and iron uptake-inefficient tomato (Solanum lycopersicum) mutant (T3238fer) plants were grown in pH-buffered hydroponic culture to investigate the direct effect of N-form on Cd uptake. Wild-type plants fed NO3− accumulated more Cd than plants fed NH4+. Iron uptake and LeIRT1 expression in roots were also greater in plants fed NO3−. However, in mutant T3238fer which loses FER function, LeIRT1 expression in roots was almost completely terminated, and the difference between NO3− and NH4+ treatments vanished. As a result, the N-form had no effect on Cd uptake in this mutant. Furthermore, suppression of LeIRT1 expression by NO synthesis inhibition with either tungstate or L-NAME, also substantially inhibited Cd uptake in roots, and the difference between N-form treatments was diminished. Considering all of these findings, it was concluded that the up-regulation of the Fe uptake system was responsible for NO3− -facilitated Cd accumulation in plants.

Work–life balance in China? Social policy, employer strategy and individual coping mechanisms

Abstract: This paper investigates major sources of work–life conflicts encountered by workers in China against a context of marketization of the economy, the rapid growth of the private sector and a trend of work intensification across occupational groups. The study shows that Chinese organizational leaders and workers tend to accept work–life conflicts as a fact of life. Individuals adopt various coping strategies on their own. While organizations are more likely to introduce human resource initiatives to cushion the negative effect of long working hours on their key employees and their families, managers are far less willing to adopt practices to accommodate childcare needs. We argue that the institutional and cultural contexts of work–life conflict and solution in China are significantly different from those found in developed economies and that the understanding of these issues has particular implications for western multinational firms operating in China.

Chitosan-based Edible Coatings for Quality Preservation of Postharvest Whiteleg Shrimp (Litopenaeus vannamei)

Abstract: Postharvest shrimp is highly susceptible to both microbiological spoilage and endogenous enzymatic browning, so it should be preserved properly using effective and appropriate methods. The effects of 1.0% and 1.5% O-carboxymethyl chitosan (CMC) and 1.0% and 1.5% chitosan (CH) coatings on the quality changes of whiteleg shrimp (Litopenaeus vannamei) during refrigerated storage (0 ± 1 °C) of 10 d were investigated. The pretreatment with CMC and CH solution (1.0% or 1.5%) retarded growth of psychrophilic bacteria throughout storage in comparison with the control (P < 0.05). The lower increases in pH and total volatile base (TVB) content were obtained in the shrimp treated with CMC and CH solution at both levels, compared with the control samples (P < 0.05). Loss in freshness and melanosis decreased after the shrimp was treated with CMC and CH. In addition, CMC and CH (1.0% or 1.5%) showed inhibitory activity toward total viable bacteria counts of white shrimp in a dose-dependent manner. Therefore, chitosan and O-carboxymethyl chitosan can be used as promising melanosis inhibitors as well as antimicrobial agents during refrigerated storage. Practical Application: The main practical application behind the development of chitosan (CH) and O-carboxymethyl chitosan (CMC) used to preserve postharvest whiteleg shrimp lies with the fact that these polysaccharides represent a renewable source of natural biodegradable polymers and meet with the emergence of more and more food safety problems. Both CMC and CH can be used as food preservatives to extend shrimp shelf life. However, CMC is more convenient due to its solubility. In the future, CMC will be used in the food processing industry because of its soluble, compatible, antimicrobial, and antioxidative characteristics.

Effect of chitosan coating enriched with thyme oil on postharvest quality and shelf life of shiitake mushroom (Lentinus edodes).

Abstract: The effect of chitosan-oil coating on the postharvest quality and shelf life of shiitake (Lentinus edodes) mushrooms stored at 4 ± 1 °C for 16 days was investigated. Mushroom weight loss, firmness, total phenolics, ascorbic acid, malondialdehyde (MDA), electrolyte leakage rate, and microbial and sensory quality were measured. The results indicate that treatment with chitosan-oil coating maintained tissue firmness, inhibited increase of respiration rate, and reduced microorganism counts, such as yeasts and molds and pseudomonad, compared to control treatment. The efficiency was better than that of thyme oil treatment or chitosan coating. Furthermore, shiitake mushrooms treated with chitosan-oil coating also exhibited significantly higher levels of total phenolics, flavonoids, as well as individual phenolic compounds than control. Sensory evaluation proved the efficacy of chitosan-oil coating by maintaining the overall quality of shiitake mushroom during the storage period. Our study suggests that chitosan-...

Active Learning for Imbalanced Sentiment Classification

Abstract: Active learning is a promising way for sentiment classification to reduce the annotation cost. In this paper, we focus on the imbalanced class distribution scenario for sentiment classification, wherein the number of positive samples is quite different from that of negative samples. This scenario posits new challenges to active learning. To address these challenges, we propose a novel active learning approach, named co-selecting, by taking both the imbalanced class distribution issue and uncertainty into account. Specifically, our co-selecting approach employs two feature subspace classifiers to collectively select most informative minority-class samples for manual annotation by leveraging a certainty measurement and an uncertainty measurement, and in the meanwhile, automatically label most informative majority-class samples, to reduce human-annotation efforts. Extensive experiments across four domains demonstrate great potential and effectiveness of our proposed co-selecting approach to active learning for imbalanced sentiment classification.

A Method to Compute Strict Minimal Siphons in a Class of Petri Nets Based on Loop Resource Subsets

Abstract: Strict minimal siphons (SMS) play an important role in the development of deadlock control policies for flexible manufacturing systems (FMS). For a class of Petri nets called Systems of Simple Sequential Processes with Resources (S3PR), the resource circuit-based method is an effective way to compute SMS. In this paper, a more effective one to compute SMS is proposed. First, the concepts of loop resource subsets and their characteristic resource subnets are proposed. Next, sufficient and necessary conditions for loop resource subsets to generate SMS are established. Finally, an algorithm is given to find all the SMS based on loop resource subsets. Since the number of loop resource subsets is much less than that of resource circuits and their combinations, the computational efficiency of the SMS enumeration task is significantly improved by the proposed method. An FMS example is used to illustrate the application of the proposed method, and computational time comparisons are provided on several S3PRs to show its superior efficiency.

Chelating agents for the treatment of systemic iron overload.

Abstract: The first successful therapeutic iron chelator was desferrioxamine which was introduced in the late 1960's by Ciba (now Novartis). Desferrioxamine has been an extremely successful compound having received the MMW "Pharmaceutical of the year" award for 1991. It is a life saving and a life - prolonging drug which improves the quality of life. However it is not orally active and its administration is both uncomfortable and expensive. Over the past twenty years there has been a growing interest in the orally active iron chelators, deferiprone and exjade, both having been extensively studied. The ability of these compounds to mobilize iron from the heart and endocrine tissue has presented the clinician with some advantages over desferrioxamine. Other orally active iron chelators are currently under development and one, FBS0701 is in clinical trial. The critical features necessary for the design of therapeutically useful iron chelators is presented in this review, together with recent studies devoted to the design of such chelators. This newly emerging range of iron chelators will enable clinicians to apply iron chelation methodology to other disease states and to begin to design personalised chelation regimes.

Andrographolide induces autophagic cell death in human liver cancer cells through cyclophilin D-mediated mitochondrial permeability transition pore.

Abstract: Liver cancer is the third leading cause of cancer death worldwide and about half of the patients with liver cancer require adjuvant therapy after surgical resection. Therefore, development of novel agents to eradicate cancer cells may constitute a viable approach to treat patients with liver cancer. Andrographolide, a diterpenoid lactone isolated from Andrographis paniculata, is known to possess potent antioxidant, anti-inflammatory, antineoplastic and antiviral properties. In this study, we investigated the cytotoxic effect of andrographolide on human liver cancer cells and explored the cell death mechanism. Andrographolide induced a cell death distinct from apoptosis in multiple human liver cancer cells. The death was characterized by autophagy as evidenced by the accumulation of LC3 II and autophagosomes, and the formation of puncta GFP-LC3. This autophagy as well as cytotoxicity caused by andrographolide could be effectively prevented by 3-methyladenine (a chemical inhibitor of autophagy). Mechanistic study indicated that andrographolide induced autophagic cell death by disruption of mitochondrial transmembrane potential and elevation of reactive oxygen species, which were correlated with mitochondrial permeability transition pore Inhibition of cyclophilin D (a component of MPTP) by cyclosporin A or abrogation of its expression by small interfering RNA significantly suppressed the cytotoxicity of andrographolide, suggesting that cyclophilin D may play an important role in mediating andrographolide-induced cytotoxicity. Taken together, our findings unveil a novel mechanism of drug action by andrographolide in liver cancer cells and suggest that andrographolide may represent a promising novel agent in the treatment of liver cancer.

One-pot template-free synthesis, growth mechanism and enhanced photocatalytic activity of monodisperse (BiO)(2)CO3 hierarchical hollow microspheres self-assembled with single-crystalline nanosheets

Abstract: This work presents a one-pot template-free synthesis, detailed characterization, growth mechanism and application of well-defined uniform monodisperse (BiO)2CO3 hierarchical hollow microspheres self-assembled with single-crystalline nanosheets. The synthesis was conducted by hydrothermal treatment of bismuth citrate and sodium carbonate in water. Time-dependent evolutions of phase structure, composition, and morphology were investigated systematically and revealed that the growth mechanism of such novel structures involved a unique multistep pathway. First, near amorphous particles were produced through reaction, nucleation, crystallization, and aggregation processes. Then, stacked embryos of intermediate (BiO)4CO3(OH)2 microspheres with attached particles were produced due to dissolution and recrystallization. Subsequently, stacked uniform solid microspheres with small particles attached on edges were generated by the consumption of particles through Ostwald ripening. The stacked microspheres further grew to form monodisperse hierarchical microspheres with a hole in the center, like flower buds. Finally, uniform monodisperse (BiO)2CO3 hierarchical hollow microspheres were produced through layers splitting. The aggregation of the self-assembled nanosheets contributed to the formation of 3D hierarchical architecture containing mesopores, which is favorable for efficient reactants transport and photo-energy harvesting. Furthermore, the band gap structure of (BiO)2CO3 was revealed by the experimental method combined with density functional theoretical calculation. As expected, the novel (BiO)2CO3 hierarchical hollow microspheres exhibited enhanced photocatalytic activity due to the special hierarchical morphology, exceeding that of (BiO)2CO3 particles and commercial P25. The as-prepared uniform (BiO)2CO3 microspheres with well-defined hierarchical hollow structures are also ideal candidates for investigating their architecture-dependent performances in other areas, such as solar energy conversion, catalysis, electronics and so on.

DDRP: An efficient data‐driven routing protocol for wireless sensor networks with mobile sinks

Abstract: SUMMARY Introduction of mobile sinks into a wireless sensor network can largely improve the network performance. However, sink mobility can cause unexpected changes of network topology, which may bring excessive protocol overhead for route maintenance and may offset the benefit from using mobile sinks. In this paper, we propose an efficient data-driven routing protocol (DDRP) to address this problem. The design objective is to effectively reduce the protocol overhead for data gathering in wireless sensor networks with mobile sinks. DDRP exploits the broadcast feature of wireless medium for route learning. Specifically, each data packet carries an additional option recording the known distance from the sender of the packet to target mobile sink. The overhearing of transmission of such a data packet will gratuitously provide each listener a route to a mobile sink. Continuous such route-learning among nodes will provide fresh route information to more and more nodes in the network. When no route to mobile sink is known, random walk routing simply is adopted for data packet forwarding. Simulation results show that DDRP can achieve much lower protocol overhead and longer network lifetime as compared with existing work while preserving high packet delivery ratio. Copyright © 2012 John Wiley & Sons, Ltd.