Priorities for, and preferred approaches to, management of New Zealand fresh waters

Since 2000 six standardised biennial public surveys of the state of the New Zealand environment have been undertaken. A fresh water case study was included in the 2010 postal survey and in an electronic survey. Desirable futures for New Zealand's fresh water resources, sources of damage to freshwater, preferred management approaches, and views about charges for commercial uses of water are reported. Respondents desire high quality water, are not prepared to trade that off for damaging economic gains, and support charges for commercial uses of water. We report public preferences for tools to manage water use.public perceptions, fresh water, New Zealand, economic instruments, management, Community/Rural/Urban Development, Environmental Economics and Policy, Health Economics and Policy, Land Economics/Use,

A toxin hunter in the microworld of bacteria: a project on novel inhibitors against bacterial AB5 toxins

[要旨] 病原性細菌が産生する蛋白性のAB5型トキシンは1個のAサブユニットと5個のBサブユニットから構成される外毒素である。両サブユニットはそれぞれ特徴的な役割を持ち，互いに巧妙に機能分担をして一つのトキシンを形成している。Aサブユニットは主に毒性に直接関与する特異的な酵素活性を有する。一方，Bサブユニットは標的細胞のレセプターに対する結合能を有し，AB5型トキシンを標的細胞に吸着させる。ここでは毒性が全く異なるAB5型トキシンとして，コレラ菌が産生するコレラトキシン（CT），腸管出血性大腸菌が産生する志賀様トキシン（Stx），及び志賀トキシン産生大腸菌が産生するサブチラーゼサイトトキシン（SubAB）の3種類に関して，その作用メカニズムに着目した毒性を抑制する阻害因子の探索などの研究を紹介する。これらの3種類のAB5型トキシンに着目した理由は，それぞれのトキシンを産生する病原菌による感染症が世界的に流行し，社会問題となっているからである。つまり，コレラ菌は依然として発展途上国で大きな問題であり，腸管出血性大腸菌のO157:H7による集団食中毒は我国でも依然として多い。さらに21世紀になり，血清型がO157:H7以外の腸管出血性大腸菌による集団食中毒が世界的に急増しているためである。いずれも抗生物質を使用した後の残留トキシンによる病態悪化が指摘されており，トキシンを効率よく無毒化する事が急務である。[SUMMARY] Bacterial AB5 toxins are proteins, produced by pathogenic bacteria including of Vibrio cholerae, Shigella dysenteriae, and enterohaemorrhagic Escherichia coli, which are usually released into the extracellular medium and cause disease by killing or altering the metabolism of target eukaryotic cells. The toxins are usually composed of one A subunit（a toxic domain） and five B subunits（a receptor-binding domain）. This article overviews the characteristics and mode of actions of AB5 toxins including cholera toxin, Shiga-like toxin, and subtilase cytotoxin, and highlights a project on the novel inhibitors against these bacterial AB5 toxins

Effects of freeze-thaw action on in vivo and in vitro bioavailability of arsenic in soils from derelict industrial sites

Arsenic is a metalloid with carcinogenic properties and has been classified as a Category I carcinogen by the International Agency for Research on Cancer (IARC). Freeze-thaw processes affect the migration and transformation of soil heavy metals, as well as adsorption/desorption and redox reactions. However, there is limited research directly addressing the impact of freeze-thaw processes on the bioavailability of soil heavy metals. In this study, we focused on As and selected As-contaminated soil samples from three types of legacy sites in heavy industrial areas. Under controlled freeze-thaw experimental conditions, we utilized both in vivo and in vitro bioavailability measurement methods to investigate whether and how freeze-thaw processes affect the bioavailability of soil As. The results of this study showed that freeze-thaw processes reduced soil pH (P < 0.05), CEC, SOM, and particle size, with decreases of 0.33, 1.2 cmol/kg, 5.2 g/kg, and 54 µm, respectively. It also increased weight specific surface area (BET) (P < 0.05), with an increase of 300 m2/kg. Freeze-thaw processes increased the proportions of exchangeable (P < 0.05), carbonate-bound, and iron-manganese oxide-bound As (P < 0.05), but reduced the proportions of organic-bound and residual As (P < 0.05). Freeze-thaw processes significantly increased the relative bioavailability and bioaccessibility of As, with increases of 32 ± 9.6% and 13 ± 0.23%, respectively. Soil pH, SOM, BET and electronic conductivity (EC) were identified as factors which could contribute to the increased bioavailability of As due to freeze-thaw processes. These results provide new insights and evidence for refining the assessment of human health risks associated with heavy metal contamination in polluted soils

Age-associated microbiome shows the giant panda lives on hemicelluloses, not on cellulose

The giant panda feeds almost exclusively on bamboo, a diet highly enriched in lignin and cellulose, but is characterized by a digestive tract similar to carnivores. It is still large unknown if and how the giant panda gut microbiota contributes to lignin and cellulose degradation. Here we show the giant pandas’ gut microbiota does not significantly contribute to cellulose and lignin degradation. We found that no operational taxonomic unit had a nearest neighbor identified as a cellulolytic species or strain with a significant higher abundance in juvenile than cubs, a very low abundance of putative lignin and cellulose genes existed in part of analyzing samples but a significant higher abundance of genes involved in starch and hemicellulose degradation in juveniles than cubs. Moreover, a significant lower abundance of putative cellulolytic genes and a significant higher abundance of putative α-amylase and hemicellulase gene families were present in giant pandas than in omnivores or herbivores

Exciton emission of quasi-2D InGaN in GaN matrix grown by molecular beam epitaxy

We investigate the emission from confined excitons in the structure of a single-monolayer-thick quasi-two-dimensional (quasi-2D) Inx Ga1-x N layer inserted in GaN matrix. This quasi-2D InGaN layer was successfully achieved by molecular beam epitaxy (MBE), and an excellent in-plane uniformity in this layer was confirmed by cathodoluminescence mapping study. The carrier dynamics have also been investigated by time-resolved and excitation-power-dependent photoluminescence, proving that the recombination occurs via confined excitons within the ultrathin quasi-2D InGaN layer even at high temperature up to ∼220 K due to the enhanced exciton binding energy. This work indicates that such structure affords an interesting opportunity for developing high-performance photonic devices

Increased CD45RA+FoxP3low Regulatory T Cells with Impaired Suppressive Function in Patients with Systemic Lupus Erythematosus

BACKGROUND: The role of naturally occurring regulatory T cells (Treg) in the control of the development of systemic lupus erythematosus (SLE) has not been well defined. Therefore, we dissect the phenotypically heterogeneous CD4(+)FoxP3(+) T cells into subpopulations during the dynamic SLE development. METHODLOGY/PRINCIPAL FINDINGS: To evaluate the proliferative and suppressive capacities of different CD4(+) T cell subgroups between active SLE patients and healthy donors, we employed CD45RA and CD25 as surface markers and carboxyfluorescein diacetatesuccinimidyl ester (CFSE) dilution assay. In addition, multiplex cytokines expression in active SLE patients was assessed using Luminex assay. Here, we showed a significant increase in the frequency of CD45RA(+)FoxP3(low) naive Treg cells (nTreg cells) and CD45RA(-)FoxP3(low) (non-Treg) cells in patients with active SLE. In active SLE patients, the increased proportions of CD45RA(+)FoxP3(low) nTreg cells were positively correlated with the disease based on SLE disease activity index (SLEDAI) and the status of serum anti-dsDNA antibodies. We found that the surface marker combination of CD25(+)CD45RA(+) can be used to defined CD45RA(+)FoxP3(low) nTreg cells for functional assays, wherein nTreg cells from active SLE patients demonstrated defective suppression function. A significant correlation was observed between inflammatory cytokines, such as IL-6, IL-12 and TNFα, and the frequency of nTreg cells. Furthermore, the CD45RA(+)FoxP3(low) nTreg cell subset increased when cultured with SLE serum compared to healthy donor serum, suggesting that the elevated inflammatory cytokines of SLE serum may promote nTreg cell proliferation/expansion. CONCLUSIONS/SIGNIFICANCE: Our results indicate that impaired numbers of functional CD45RA(+)FoxP3(low) naive Treg cell and CD45RA(-)FoxP3(low) non-suppressive T cell subsets in inflammatory conditions may contribute to SLE development. Therefore, analysis of subsets of FoxP3(+) T cells, using a combination of FoxP3, CD25 and CD45RA, rather than whole FoxP3(+) T cells, will help us to better understand the pathogenesis of SLE and may lead to the development of new therapeutic strategies

Tourism and the sustainable livelihoods approach: Application within the Chinese context : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Lincoln University

Tourism has been increasingly used for, and directly linked with, rural poverty reduction in developing countries. In recent years, it has, however, been criticised by rural developers for its lack of concern for the rural poor and for being too increasingly focused on tourism specifically. Instead, it is argued that these inadequacies can be addressed by the Sustainable Livelihoods Approach (SLA), a widely used organising framework for facilitating poverty reduction. But the application, and to an extent the principles, of the SLA may not fully fit the tourism situation, and vice versa. Therefore, a comprehensive understanding about the relationship between the SLA and tourism needs to be explored. This thesis incorporates a review of the literature on rural and tourism development. Gaps between the SLA and tourism are identified. It is suggested that the SLA cannot fully address the issues when tourism is used as a rural livelihood strategy. New knowledge and thinking are needed. Based on the literature review, a Sustainable Livelihoods Framework for Tourism (SLFT) is proposed as a guiding tool in rural development when tourism is a livelihood strategy. For testing the applicability of the SLFT, a mixed methodology and case study research method was adopted. Three mountainous rural villages, respectively at involvement, development and rejuvenation Tourism Area Life Cycle (TALC) stages, in central China, were examined. Before implementation of the case study, SLFT indicators were firstly developed. Findings show that the SLFT provides an overall organising framework for the consideration of rural development using tourism as a livelihood strategy at all stages of TALC. Revisiting the SLFT, it is argued that an additional attraction capital should be added to the SLFT. Attraction capital includes natural, cultural, and other attractions, and is defined as all resources used to attract tourist arrivals from which local people benefit for better livelihood objectives. Based on the findings, the SLFT and its key elements are revised to offer a more complete insight and understanding of a tourism livelihood system for the purpose of tourism planning and management. Particular attention is drawn to the newly introduced concept of institutional capital, mainly evidenced in community participation practice. Appropriate institutional policies and practices can ensure local people share the benefits from tourism. The implication of a participatory approach is extended to access to tourist markets, benefit sharing, as well as participation in the decision-making. This research indicates that improvement of livelihood assets by tourism enhances local people’s resilience to vulnerability contexts. Institutional arrangements play an important role in mediating this process as well as the impact of vulnerability contexts through the planning portfolio (e.g., planning, policy-making, and legislation). Future research is suggested to evaluate and improve the SLFT’s applicability in multiple development contexts, and to explore ways of further developing SLFT indicators as a means for evaluating the usefulness of the SLFT

Railway Static Power Conditioners For High-Speed Train Traction Power Supply Systems Using Three-Phase V/V Transformers

In order to eliminate the negative-sequence and harmonic currents in the high-speed train traction systems with three-phase V/V transformers, a compensation strategy based on the railway static power conditioners (RPC) is proposed in this paper. An RPC contains two converters that are connected back to back by sharing the same dc link. In this paper, the structure and principle to compensate negative-sequence currents for the RPC with a three-phase V/V transformer are explained, and a strategy to provide the compensation references for negative-sequence and harmonic currents is proposed. Also, a method to separate active current, reactive current, and harmonic current references from the total negative-sequence and harmonic current references is given. Moreover, a controller is proposed to maintain the dc-link voltage and to compensate the negative-sequence and harmonic currents. Simulation and experimental results are provided to demonstrate that the proposed strategy is very effective. © 2011 IEEE