Concepts and tools for comprehensive sustainability assessments for tourism destinations: a comparative review

This paper reviews a wide range of tools for comprehensive sustainability assessments at whole tourism destinations, covering socio-cultural, economic and environmental issues. It considers their strengths, weaknesses and site specific applicability. It is intended to facilitate their selection (and combination where necessary). Tools covered include Sustainability Indicators, Environmental Impact Assessment, Life Cycle Assessment, Environmental Audits, Ecological Footprints, Multi-Criteria Analysis and Adaptive Environmental Assessment. Guidelines for evaluating their suitability for specific sites and situations are given as well as examples of their use.

Adaptive multiscale principal components analysis for online monitoring of wastewater treatment

Fault detection and isolation (FDI) are important steps in the monitoring and supervision of industrial processes. Biological wastewater treatment (WWT) plants are difficult to model, and hence to monitor, because of the complexity of the biological reactions and because plant influent and disturbances are highly variable and/or unmeasured. Multivariate statistical models have been developed for a wide variety of situations over the past few decades, proving successful in many applications. In this paper we develop a new monitoring algorithm based on Principal Components Analysis (PCA). It can be seen equivalently as making Multiscale PCA (MSPCA) adaptive, or as a multiscale decomposition of adaptive PCA. Adaptive Multiscale PCA (AdMSPCA) exploits the changing multivariate relationships between variables at different time-scales. Adaptation of scale PCA models over time permits them to follow the evolution of the process, inputs or disturbances. Performance of AdMSPCA and adaptive PCA on a real WWT data set is compared and contrasted. The most significant difference observed was the ability of AdMSPCA to adapt to a much wider range of changes. This was mainly due to the flexibility afforded by allowing each scale model to adapt whenever it did not signal an abnormal event at that scale. Relative detection speeds were examined only summarily, but seemed to depend on the characteristics of the faults/disturbances. The results of the algorithms were similar for sudden changes, but AdMSPCA appeared more sensitive to slower changes.

Learning, odour preference and flower foraging in moths

Floral volatiles play a major role in plant-insect communication. We examined the influence of two volatiles, phenylacetaldehyde and a-pinene, on the innate and learnt foraging behaviour of the moth Helicoverpa armigera. In dual-choice wind tunnel tests, adult moths flew upwind towards both volatiles, with a preference for phenylacetaldehyde. When exposure to either of these volatiles was paired with a feeding stimulus (sucrose), all moths preferred the learnt odour in the preference test. This change in preference was not seen when moths were exposed to the odour without a feeding stimulus. The learnt preference for the odour was reduced when moths were left unfed for 24 h before the preference test. We tested whether moths could discriminate between flowers that differed in a single volatile component. Moths were trained to feed on flowers that were odour-enhanced using either phenylacetaldehyde or a-pinene. Choice tests were then carried out in an outdoor flight cage, using flowers enhanced with either volatile. Moths showed a significant preference for the flower type on which they were trained. Moths that were conditioned on flowers that were not odour-enhanced showed no preference for either of the odour-enhanced flower types. The results imply that moths may be discriminating among odour profiles of individual flowers from the same species. We discuss this behaviour within the context of nectar foraging in moths and odour signalling by flowering plants.

A polytope DNA vaccine elicits multiple effector and memory CTL responses and protects against human papillomavirus 16 E7-expressing tumour

Vaccine-induced CD8 T cells directed to tumourspecific antigens are recognised as important components of protective and therapeutic immunity against tumours. Where tumour antigens have pathogenic potential or where immunogenic epitopes are lost from tumours, development of subunit vaccines consisting of multiple individual epitopes is an attractive alternative to immunising with whole tumour antigen. In the present study we investigate the efficacy of two DNA-based multiepitope('polytope') vaccines containing murine (H-2(b)) and human (HLA-A* 0201)-restricted epitopes of the E7 oncoprotein of human papillomavirus type 16, in eliciting tumour-protective cytotoxic T-lymphocyte (CTL) responses. We show that the first of these polytopes elicited powerful effector CTL responses ( measured by IFN-gamma ELISpot) and long-lived memory CTL responses ( measured by functional CTL assay and tetramers) in immunised mice. The responses could be boosted by immunisation with a recombinant vaccinia virus expressing the polytope. Responses induced by immunisation with polytope DNA alone partially protected against infection with recombinant vaccinia virus expressing the polytope. Complete protection was afforded against challenge with an E7-expressing tumour, and reduced growth of nascent tumours was observed. A second polytope differing in the exact composition and order of CTL epitopes, and lacking an inserted endoplasmic reticulum targeting sequence and T-helper epitope, induced much poorer CTL responses and failed to protect against tumour challenge. These observations indicate the validity of a DNA polytope vaccine approach to human papillomavirus E7 - associated carcinoma, and underscore the importance of design in polytope vaccine construction.

Active and passive immunization against oral Candida albicans infection in a murine model

Background/aims: Clinical and laboratory studies are consistent with a major role for cell-mediated immunity in recovery from oral infection with Candida albicans, but the role of humoral immunity remains controversial. The purpose of this study was to establish the relative contributions of cellular and humoral immunity to protection against oral candidiasis in a murine model, and to determine whether host responses could be enhanced by different immunization strategies. Results: Active oral immunization was protective in BALB/c and CBA/CaH mice, reducing both fungal burden and duration of infection after secondary challenge, whereas systemic immunization failed to protect against subsequent oral challenge. Candida-specific IgM was the predominant antibody detected in serum following both primary and secondary oral challenge; however, Candida-specific salivary IgA was not detectable. Immunization by passive transfer of either lymphocytes or immune serum did not confer any significant protection against oral infection in either susceptible or resistant mouse strain. Conclusion: The data demonstrate a possible role for mucosa-associated immunity following active immunization by the oral route, most likely exerted by local T lymphocytes resident in the oral mucosa, but there was no evidence to support a role for humoral immunity in protection against oral candidiasis.

Degrees of freedom and motor planning in purposive movement

This paper presents empirical evidence suggesting that healthy humans can perform a two degree of freedom visuo-motor pursuit tracking task with the same response time delay as a one degree of freedom task. In contrast, the time delay of the response is influenced markedly by the nature of the motor synergy required to produce it. We suggest a conceptual account of this evidence based on adaptive model theory, which combines theories of intermittency from psychology and adaptive optimal control from engineering. The intermittent response planning stage has a fixed period. It possesses multiple optimal trajectory generators such that multiple degrees of freedom can be planned concurrently, without requiring an increase in the planning period. In tasks which require unfamiliar motor synergies, or are deemed to be incompatible, internal adaptive models representing movement dynamics are inaccurate. This means that the actual response which is produced will deviate from the one which is planned. For a given target-response discrepancy, corrective response trajectories of longer duration are planned, consistent with the principle of speed-accuracy trade-off. Compared to familiar or compatible tasks, this results in a longer response time delay and reduced accuracy. From the standpoint of the intermittency approach, the findings of this study help make possible a more integral and predictive account of purposive action. (c) 2005 Elsevier B.V. All rights reserved.

Fault-tolerant quantum computation with cluster states

The one-way quantum computing model introduced by Raussendorf and Briegel [Phys. Rev. Lett. 86, 5188 (2001)] shows that it is possible to quantum compute using only a fixed entangled resource known as a cluster state, and adaptive single-qubit measurements. This model is the basis for several practical proposals for quantum computation, including a promising proposal for optical quantum computation based on cluster states [M. A. Nielsen, Phys. Rev. Lett. (to be published), quant-ph/0402005]. A significant open question is whether such proposals are scalable in the presence of physically realistic noise. In this paper we prove two threshold theorems which show that scalable fault-tolerant quantum computation may be achieved in implementations based on cluster states, provided the noise in the implementations is below some constant threshold value. Our first threshold theorem applies to a class of implementations in which entangling gates are applied deterministically, but with a small amount of noise. We expect this threshold to be applicable in a wide variety of physical systems. Our second threshold theorem is specifically adapted to proposals such as the optical cluster-state proposal, in which nondeterministic entangling gates are used. A critical technical component of our proofs is two powerful theorems which relate the properties of noisy unitary operations restricted to act on a subspace of state space to extensions of those operations acting on the entire state space. We expect these theorems to have a variety of applications in other areas of quantum-information science.

Report of the equine herpesvirus-1 Havermeyer Workshop, San Gimignano, Tuscany, June 2004

Amongst the infectious diseases that threaten equine health, herpesviral infections remain a world wide cause of serious morbidity and mortality. Equine herpesvirus-1 infection is the most important pathogen, causing an array of disorders including epidemic respiratory disease abortion, neonatal foal death, myeloencephalopathy and chorioretinopathy. Despite intense scientific investigation, extensive use of vaccination, and established codes of practice for control of disease outbreaks, infection and disease remain common. While equine herpesvirus-1 infection remains a daunting challenge for immunoprophylaxis, many critical advances in equine immunology have resulted in studies of this virus, particularly related to MHC-restricted cytotoxicity in the horse. A workshop was convened in San Gimignano, Tuscany, Italy in June 2004, to bring together clinical and basic researchers in the field of equine herpesvirus-1 study to discuss the latest advances and future prospects for improving our under-standing of these diseases, and equine immunity to herpesviral infection. This report highlights the new information that was the focus of this workshop, and is intended to summarize this material and identify the critical questions in the field. (c) 2006 Elsevier B.V. All rights reserved.

Continued discovery of transcriptional units expressed in cells of the mouse mononuclear phagocyte lineage

The current RIKEN transcript set represents a significant proportion of the mouse transcriptome but transcripts expressed in the innate and acquired immune systems are poorly represented. In the present study we have assessed the complexity of the transcriptome expressed in mouse macrophages before and after treatment with lipopolysaccharide, a global regulator of macrophage gene expression, using existing RIKEN 19K arrays. By comparison to array profiles of other cells and tissues, we identify a large set of macrophage-enriched genes, many of which have obvious functions in endocytosis and phagocytosis. In addition, a significant number of LPS-inducible genes were identified. The data suggest that macrophages are a complex source of mRNA for transcriptome studies. To assess complexity and identify additional macrophage expressed genes, cDNA libraries were created from purified populations of macrophage and dendritic cells, a functionally related cell type. Sequence analysis revealed a high incidence of novel mRNAs within these cDNA libraries. These studies provide insights into the depths of transcriptional complexity still untapped amongst products of inducible genes, and identify macrophage and dendritic cell populations as a starting point for sampling the inducible mammalian transcriptome.

Experimental evidence for multivariate stabilizing sexual selection

Stabilizing selection is a fundamental concept in evolutionary biology. In the presence of a single intermediate optimum phenotype (fitness peak) on the fitness surface, stabilizing selection should cause the population to evolve toward such a peak. This prediction has seldom been tested, particularly for suites of correlated traits. The lack of tests for an evolutionary match between population means and adaptive peaks may be due, at least in part, to problems associated with empirically detecting multivariate stabilizing selection and with testing whether population means are at the peak of multivariate fitness surfaces. Here we show how canonical analysis of the fitness surface, combined with the estimation of confidence regions for stationary points on quadratic response surfaces, may be used to define multivariate stabilizing selection on a suite of traits and to establish whether natural populations reside on the multivariate peak. We manufactured artificial advertisement calls of the male cricket Teleogryllus commodus and played them back to females in laboratory phonotaxis trials to estimate the linear and nonlinear sexual selection that female phonotactic choice imposes on male call structure. Significant nonlinear selection on the major axes of the fitness surface was convex in nature and displayed an intermediate optimum, indicating multivariate stabilizing selection. The mean phenotypes of four independent samples of males, from the same population as the females used in phonotaxis trials, were within the 95% confidence region for the fitness peak. These experiments indicate that stabilizing sexual selection may play an important role in the evolution of male call properties in natural populations of T. commodus.

Intelligent agent supported personalization for virtual learning environments

Virtual learning environments (VLEs) are computer-based online learning environments, which provide opportunities for online learners to learn at the time and location of their choosing, whilst allowing interactions and encounters with other online learners, as well as affording access to a wide range of resources. They have the capability of reaching learners in remote areas around the country or across country boundaries at very low cost. Personalized VLEs are those VLEs that provide a set of personalization functionalities, such as personalizing learning plans, learning materials, tests, and are capable of initializing the interaction with learners by providing advice, necessary instant messages, etc., to online learners. One of the major challenges involved in developing personalized VLEs is to achieve effective personalization functionalities, such as personalized content management, learner model, learner plan and adaptive instant interaction. Autonomous intelligent agents provide an important technology for accomplishing personalization in VLEs. A number of agents work collaboratively to enable personalization by recognizing an individual's eLeaming pace and reacting correspondingly. In this research, a personalization model has been developed that demonstrates dynamic eLearning processes; secondly, this study proposes an architecture for PVLE by using intelligent decision-making agents' autonomous, pre-active and proactive behaviors. A prototype system has been developed to demonstrate the implementation of this architecture. Furthemore, a field experiment has been conducted to investigate the performance of the prototype by comparing PVLE eLearning effectiveness with a non-personalized VLE. Data regarding participants' final exam scores were collected and analyzed. The results indicate that intelligent agent technology can be employed to achieve personalization in VLEs, and as a consequence to improve eLeaming effectiveness dramatically.

The clinical effectiveness of a multisensory therapy on clients with developmental disability

Many clients in Hong Kong with developmental disabilities stay in mental hospitals because of mental disorders and behavioural problems. There is a need to identify strategies that promote psychological well-being and reduce problem behaviours in this group of clients. This study evaluates the impact of multisensory therapy on participants’ emotional state, level of relaxation, challenging behaviour, stereotypic self-stimulating behaviour (SSB) and adaptive behaviour (AB). Using an experimental design, 89 participants were recruited from a developmental disability unit in a hospital in Hong Kong and randomly assigned to either an experimental (n = 48) or a control group (n = 41). Multisensory therapy sessions (n = 36) were conducted with experimental group and activity sessions (n = 36) were conducted with controls for 12 weeks. Multisensory therapy promoted participants’ positive emotions and relaxation. However, there was no evidence that multisensory therapy was superior to activity therapy in reducing aggressive behaviour and stereotypic self-stimulating behaviour or promoting adaptive behaviour. The key variables that influence clients’ behaviours in the multisensory therapy may be related to the relationship with the carer, constant environment, relaxation and freedom from demands rather than sensory input. Multisensory therapy could be used to provide leisure and promote psychological well-being, rather than for reducing problem behaviour.

The anti-tumor activity of IL-12: Mechanisms of innate immunity that are model and dose dependent

IL-12 has been demonstrated to have potent anti-tumor activities in a variety of mouse tumor models, but the relative roles of NK, NKT, and T cells and their effector mechanisms in these responses have not been fully addressed. Using a spectrum of gene-targeted or Ab-treated mice we have shown that for any particular tumor model the effector mechanisms downstream of IL-12 often mimic the natural immune response to that tumor. For example, metastasis of the MHC class I-deficient lymphoma, EL4-S3, was strictly controlled by NK cells using perforin either naturally or following therapy with high-dose IL-12. Intriguingly, in B16F10 and RM-1 tumor models both NK and NKT cells contribute to natural protection from tumor metastasis, In these models, a lower dose of IL-12 or delayed administration of IL-12 dictated a greater relative role of NKT cells in immune protection from tumor metastasis. Overall, both NK and NKT cells can contribute to natural and IL-12-induced immunity against tumors, and the relative role of each population is turner and therapy dependent.

Alternatives to conventional vaccines - Mediators of innate immunity

Vaccines have been described as weapons of mass protection. The eradication of many diseases is testament to their utility and effectiveness. Nevertheless, many vaccine preventable diseases remain prevalent because of political and economic barriers. Additionally, the effects of immaturity and old age, therapies that incapacitate the adaptive immune system and the multitude of strategies evolved by pathogens to evade immediate or sustained recognition by the mammalian immune system are barriers to the effectiveness of existing vaccines or development of new vaccines. In the front line of defence against the pervasiness of infection are the elements of the innate immune system. Innate immunity is under studied and poorly appreciated. However, in the first days after entry of a pathogen into the body, our entire protective response is dependant upon the various elements of our innate immune repertoire. In spite of, its place as our initial defence against infection, attention is only now turning to strategies which enhance or supplement innate immunity. This review examines the need for and potential of innate immune therapies.

Mechanisms of hematopoietic stem cell mobilization: When innate immunity assails the cells that make blood and bone

Mobilization is now used worldwide to collect large numbers of hematopoietic stem and progenitor cells (HSPCs) for transplantation. Although the first mobilizing agents were discovered largely by accident, discovery of more efficient mobilizing agents will require a better understanding of the molecular mechanisms responsible. During the past 5 years, a number of mechanisms have been identified, shedding new light on the dynamics of the hematopoietic system in vivo and on the intricate relationship between hematopoiesis, innate immunity, and bone. After briefly reviewing the mechanisms by which circulating HSPCs home into the bone marrow and what keeps them there, the current knowledge of mechanisms responsible for HSPC mobilization in response to hematopoietic growth factors such as granulocyte colony-stimulating factor, chemotherapy, chemokines, and polyanions will be discussed together with current strategies developed to further increase HSPC mobilization. (c) 2006 International Society for Experimental Hematology.