Measurements of Growth Rates of (0001) Ice Crystal Surfaces

We present measurements of growth rates of the (0001) facet surface of ice as a function of water vapor supersaturation over the temperature range $-2$ $\geq T\geq -40$ C. From these data we infer the temperature dependence of premelting on the basal surface and the effects of premelting on the ice growth dynamics. Over this entire temperature range the growth was consistent with a simple 2D nucleation model, allowing a measurement of the critical supersaturation $\sigma _{0}(T)$ as a function of temperature. We find that the 2D nucleation barrier is substantially diminished when the premelted layer is partially developed, as indicated by a reduced $\sigma _{0},$ while the barrier is higher both when the premelted layer is fully absent or fully developed

Factorial Design Applied to Waste Immobilisation in Geopolymer-based Systems

Concentrated alkali, ground glass and air pollution control residues were mixed in various proportions and cured for up to 28 days. These blocks were tested in strength and analysed by thermal gravimetric analysis to assess the success of the geopolymerisation process. A Taguchi factorial design approach was then adopted to investigate the effects of different variables upon the strength development of these blocks

In-situ and Remote Sensing Networks for Environmental Monitoring and Global Assessment of Leptospirosis Outbreaks

AbstractLeptospirosis is a disease that affects human population and can claim many victims with large outbreaks associated with natural disasters. This work focuses on the technological aspects for inexpensive climate monitoring techniques based on ground and satellite sensors for obtaining information prior to disease outbreaks in under-developed regions and on water-quality sensors that can lead to radical changes in our ability to detect and abate this disease. The remote deployment of such sensors in areas where outbreaks can occur can help in enhancingin real-time the spatial and temporal resolution of information and allows unattended operation that will be particularly useful for monitoring under extreme climate events. Such types of monitoring advancements, when coupled with regular geographical, population and habitat monitoring can assess the hazards and risks to local population prior to a disease outbreak. Then in the eventual aftermath, it can assist in identification of affected geographical locations where abatement solutions will be required, and eventually in the assessment of the effectiveness of control measures. This work explores recent releases of open global observation data and a range of in-situ environmental monitoring tools of increasing complexity for measuring several parameters andfor detecting contaminants and pathogens that were previously irresolvable due to the high degree of complexityinthe diagnosis of this disease

Barriers to Adopting a Plant-Based Diet in High-Income Countries: A Systematic Review.

Adopting a plant-based diet (PBD) has been shown to reduce the risk of developing certain diseases and is linked to environmental benefits. This review synthesises the evidence on the barriers adults aged 18 to 65 living in high-income countries (HIC) may experience when adopting a PBD. A systematic literature review was conducted using four search databases: Medline, Embase, Global Health, and Web of Science. Barriers were mapped to behaviour change strategies using the COM-B model. Ten studies were included in the final review, including 1740 participants. Five were qualitative, four were cross-sectional, and one was a pre- and-post-intervention study. In total, 40 barriers were identified and synthesised into 11 themes: financial, lack of knowledge, emotional, health, convenience, social, enjoyment of meat, environmental, accessibility, personal ability, and media. Of the 40 barriers, nutritional intake/requirements (categorised into the "health" theme) had the most evidence. This barrier encompassed concerns around being able to meet nutritional needs if an individual were to adopt a PBD. Habits (in the "personal ability" theme), which included established eating habits and habitual behaviours relating to animal-source foods, had the second most evidence alongside the barrier of not knowing what to eat as part of a PBD (in the "lack of knowledge" theme). Education interventions and communication/marketing policies were the behaviour change mechanisms mapped onto these barriers. Future interventions should focus on informing individuals about what to consume as part of a nutritionally balanced PBD and facilitating habitual dietary change

Application of nanoscale zero valent iron (NZVI) for groundwater remediation in Europe

Purpose: Nanoscale zero valent iron (NZVI) is emerging as a new option for the treatment of contaminated soil and groundwater targeting mainly chlorinated organic contaminants (e.g., solvents, pesticides) and inorganic anions or metals. The purpose of this article is to give a short overview of the practical experience with NZVI applications in Europe and to present a comparison to the situation in the USA. Furthermore, the reasons for the difference in technology use are discussed. Method: The results in this article are based on an extensive literature review and structured discussions in an expert workshop with experts from Europe and the USA. The evaluation of the experiences was based on a SWOT (strength, weakness, opportunity, threat) analysis. Result: There are significant differences in the extent and type of technology used between NZVI applications in Europe and the USA. In Europe, only three full-scale remediations with NZVI have been carried out so far, while NZVI is an established treatment method in the USA. Bimetallic particles and emulsified NZVI, which are extensively used in the USA, have not yet been applied in Europe. Economic constraints and the precautionary attitude in Europe raise questions regarding whether NZVI is a cost-effective method for aquifer remediation. Challenges to the commercialization of NZVI include mainly non-technical aspects such as the possibility of a public backlash, the fact that the technology is largely unknown to consultants, governments and site owners as well as the lack of long-term experiences. Conclusion: Despite these concerns, the results of the current field applications with respect to contaminant reduction are promising, and no major adverse impacts on the environment have been reported so far. It is thus expected that these trials will contribute to promoting the technology in Europ

Interpreting and acting upon home blood pressure readings: A qualitative study

This article is made available through the Brunel Open Access Publishing Fund. Copyright @ 2013 Vasileiou et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background: Recent guidelines recognize the importance of home blood pressure monitoring (HBPM) as an adjunct to clinical measurements. We explored how people who have purchased and use a home blood pressure (BP) monitor make sense of, and act upon, readings and how they communicate with their doctor about the practice of home monitoring. Methods: A qualitative study was designed and participants were purposively recruited from several areas in England, UK. Semi-structured in-depth interviews were conducted with 18 users of home BP monitors. The transcribed data were thematically analysed. Results: Interpretation of home BP readings is complex, and is often characterised by uncertainty. People seek to assess value normality using ‘rules of thumb’, and often aim to identify the potential causes of the readings. This is done by drawing on lay models of BP function and by contextualising the readings to personal circumstances. Based on the perceived causes of the problematic readings, actions are initiated, mostly relating to changes in daily routines. Contacting the doctor was more likely when the problematic readings persisted and could not be easily explained, or when participants did not succeed in regulating their BP through their other interventions. Most users had notified their doctor of the practice of home monitoring, but medical involvement varied, with some participants reporting disinterest or reservations by doctors. Conclusions: Involvement from doctors can help people overcome difficulties and resolve uncertainties around the interpretation of home readings, and ensure that the rules of thumb are appropriate. Home monitoring can be used to strengthen the patient-clinician relationship

Characterisation of an Escherichia coli line that completely lacks ribonucleotide reduction yields insights into the evolution of parasitism and endosymbiosis

Life requires ribonucleotide reduction for de novo synthesis of deoxyribonucleotides. As ribonucleotide reduction has on occasion been lost in parasites and endosymbionts, which are instead dependent on their host for deoxyribonucleotide synthesis, it should in principle be possible to knock this process out if growth media are supplemented with deoxyribonucleosides. We report the creation of a strain of Escherichia coli where all three ribonucleotide reductase operons have been deleted following introduction of a broad spectrum deoxyribonucleoside kinase from Mycoplasma mycoides. Our strain shows slowed but substantial growth in the presence of deoxyribonucleosides. Under limiting deoxyribonucleoside levels, we observe a distinctive filamentous cell morphology, where cells grow but do not appear to divide regularly. Finally, we examined whether our lines can adapt to limited supplies of deoxyribonucleosides, as might occur in the switch from de novo synthesis to dependence on host production during the evolution of parasitism or endosymbiosis. Over the course of an evolution experiment, we observe a 25-fold reduction in the minimum concentration of exogenous deoxyribonucleosides necessary for growth. Genome analysis reveals that several replicate lines carry mutations in deoB and cdd. deoB codes for phosphopentomutase, a key part of the deoxyriboaldolase pathway, which has been hypothesised as an alternative to ribonucleotide reduction for deoxyribonucleotide synthesis. Rather than complementing the loss of ribonucleotide reduction, our experiments reveal that mutations appear that reduce or eliminate the capacity for this pathway to catabolise deoxyribonucleotides, thus preventing their loss via central metabolism. Mutational inactivation of both deoB and cdd is also observed in a number of obligate intracellular bacteria that have lost ribonucleotide reduction. We conclude that our experiments recapitulate key evolutionary steps in the adaptation to life without ribonucleotide reduction