Predatory Bdellovibrio bacteria use gliding motility to scout for prey on surfaces

Bdellovibrio bacteriovorus is a famously fast, flagellate predatory bacterium, preying upon Gram-negative bacteria in liquids; how it interacts with prey on surfaces such as in medical biofilms is unknown. Here we report that Bdellovibrio bacteria "scout" for prey bacteria on solid surfaces, using slow gliding motility that is present in flagellum-negative and pilus-negative strains.

Labour Law as Human Rights Law: A Critique of the Use of ‘Dignity’ by Freedland and Kountouris

In their recent book, The Legal Construction of Personal Work Relations, Mark Freedland and Nicola Kountouris present an ambitious study of the personal scope of (what they would not want to call) ‘employment’ law. The book does this within a broader argument that calls for the reconceptualization of labour law as a whole, and it is this broader argument on which I shall focus in this chapter. Their aim, in urging us to see labour law through the lens of ‘dignity’ is to bring labour law and human rights law into closer alignment than has sometimes been the case in the past. Increasingly, dignity is seen as providing a, sometimes the, foundation of human rights law, particularly in Europe. I shall suggest that whilst the aim of constructing a new set of foundations for labour law is a worthy and increasingly urgent task, the concepts on which Freedland and Kountouris seek to build their project pose significant difficulties. In particular, their espousal of ‘dignity’ presents problems that must be addressed if their reconceptualization is not to prove a blind alley.

Children's use of interventions to learn causal structure

Children aged between 5 and 8 years freely intervened on a three-variable causal system, with their task being to discover whether it was a common-cause structure or one of two causal chains. From 6-7 years, children were able to use information from their interventions to correctly disambiguate the structure of a causal chain. We used a Bayesian model to examine children’s interventions on the system; this showed that with development children became more efficient in producing the interventions needed to disambiguate the causal structure and that the quality of interventions, as measured by their informativeness, improved developmentally. The latter measure was a significant predictor of children’s correct inferences about the causal structure. A second experiment showed that levels of performance were not reduced in a task in which children did not select and carry out interventions themselves, indicating no advantage for self-directed learning. However, children’s performance was not related to intervention quality in these circumstances, suggesting that children learn in a different way when they carry out interventions themselves.

The Historical Use of Amnesties, Immunities, and Sentence Reductions in Northern Ireland

While it is widely believed that the use of amnesties and similar measures would mark a new departure in NI and the UK, so that speculation about their introduction causes public controversy and threatens political instability, the report demonstrates that such measures have in fact been repeatedly used in a wide range of circumstances since the foundation of the NI state. The paper offers definitions of the key measures which have been employed, including amnesties, sentence reductions linked to peace building and use immunities. It explores their historical use and its consequences.

Mineralogical and chemical characterization of some vermiculites from the mozambique belt of tanzania for agricultural use

Vermiculite minerals are locally available in the Mozambique Belt of Tanzania but are not currently commercially exploited. In part this may be due to lack of any precise characterization. This study was carried out as a first step to assess the suitability of these vermiculites for crop production by characterization of their mineralogical and chemical compositions. X-ray diffraction and scanning electron microscopy combined with an energydispersive X-ray system were used to establish the mineralogy. Electron microprobe analysis and inductively coupled plasma-mass spectrometry were used to study the chemical compositions and to identify any possible issues related to chemical composition that might affect their use if applied as soil conditioners. The samples were characterized as vermiculites and hydrobiotites with a wide variety of accessory minerals. Accessory minerals that might be of some concern are galena, fibrous amphiboles and sepiolite. The total levels of Ni in all vermiculites, and Cr in some, were also found to be high relative to common European standards and this might limit their potential as soil conditioners. It is clear that a field assessment of the bioavailability of various elements would be necessary before decisions relating to potential agricultural use could be made. © 2009 The Mineralogical Society.

Land use history of Village Bay, Hirta, St Kilda World Heritage Site:A palynological investigation of plaggen soils

This paper presents findings based on a palynological investigation of artificially accreting (plaggen) soils from the settlement of Village Bay, Hirta, in the St Kilda archipelago, which was perhaps the most distant and inhospitable outpost of sustained human habitation in the British Isles. The soils were developed principally through the addition of turf ash and seabird waste, although some ash may have been derived from upland peats. It is assumed that the woodland pollen signal (much lower in the soils than in an upland peat site nearby) represents off-island sources. Corylus avellana-type pollen (frequent in upland sites), along with Potentilla-type, may provide markers in the Village Bay profiles for the addition of ashed hillside turf, and possibly peat, to the plaggen soils. Cereal-type pollen is well represented through the profiles and is often strongly associated with the record for Chrysanthemum segetum (corn marigold), a frequent indicator of arable land. The Brassicaceae signal may partly reflect the cultivation of cabbages; Chelidonium majus (greater celandine) may have been grown for medicinal use. Soil mixing has rendered radiocarbon dating meaningless at this site, but the establishment of a change in cultivation regime before AD 1830 may have been identified from the patterns of pollen concentration and preservation in the profiles. © 2008 Elsevier B.V. All rights reserved.

Development and testing of an intermediate temperature glass sealant for use in mixed ionic and electronic conducting membrane reactors

High temperature ceramic membranes have interesting possibilities for application in areas of new and developing technologies such as hydrocarbon combustion with carbon dioxide capture and electrochemical promotion of catalysis (EPOC). However, membrane module sealing remains a significant technical challenge. In this work a borosilicate glass sealant (50SiO₂·25B₂O₃·25Na₂O, mol%) was developed to fit the requirements of sealing an air separation membrane system at intermediate temperatures (300-600 °C). The seal was assessed by testing the leak rates under a range of conditions. The parameters tested included the effect of flowrate on the leak rate, the heating and cooling rates of the reactor and the range of temperatures under which the system could operate. Tests for durability and reliability were also performed. It was found that the most favourable reactor configuration employed a reactor with the ceramic pellet placed underneath the inner chamber alumina tube (inverted configuration), using a quartz wool support to keep the membrane in place prior to sealing. Using this configuration the new glass-based seal was found to be a more suitable sealant than traditional alternatives; it produced lower leak rates at all desirable flowrates, with the potential for rapid heating and cooling and multiple cycling, allowing for prolonged usage. © 2010 Elsevier B.V. All rights reserved.

The Use of High Surface Area Silica and Supercritical Carbon Dioxide to Enhance Solubility of Poorly Water-Soluble Drugs

Purpose Poor water-solubility of BCS class II drugs can limit their commercialization because of reduced oral bioavailability. It has been reported that loading of drug by adsorption onto porous silica would enhance drug solubility due to the increased surface area available for solvent diffusion. In this work, solid dispersions are formed using supercritical carbon dioxide (scCO2). The aim of this research was to characterise the solid-state properties of scCO2 dispersion and to investigate the impact of altering scCO2 processing conditions on final amorphous product performance that could lead to enhancement of drug dissolution rate for BCS class II drugs. Methods Indomethacin (IND) was purchased from Sigma-Aldrich (Dorset, UK) and was used as a model drug with two grades of high surface area silica (average particle sizes 3&[micro] and 7&[micro]), which were obtained directly from Grace-Davison (Germany). Material crystallinity was evaluated using powder X-ray diffraction (PXRD, Rigaku™, miniflex II, Japan) and high-speed differential scanning calorimetry (Hyper-DSC 8000, Perkin Elmer, USA). Materials were placed in a high-pressure vessel consisting of a CO2 cylinder, a Thar™ Technologies P50 high-pressure pump and a 750 ml high-pressure vessel (Thar, USA). Physical mixtures were exposed to CO2 gas above its critical conditions. SEM imaging and elemental analysis were conducted using a Jeol 6500 FEGSEM (Advanced MicroBeam Inc., Austria). Drug release was examined using USP type II dissolution tester (Caleva™, UK). Results The two grades of silica were found to be amorphous using PXRD and Hyper-DSC. Using PXRD, it was shown that an increase in incubation time and pressure resulted in a decrease in the crystalline content. Drug release profiles from the two different silica formulations prepared under the same conditions are shown in Figure 1. It was found that there was a significant enhancement in drug release, which was influenced, by silica type and other experiment conditions such as temperature, pressure and exposure time. SEM imaging and elemental analysis showed drug deposited inside silica pores as well as on the outer surface. Conclusion This project has shown that silica carrier platforms may be used as an alternative approach to generating polymeric solid dispersions of amorphous drugs exhibiting enhanced solubility.

Performance of sustainable SCC mixes with mineral additions for use in precast concrete industry

The aim of this research was to study the impact that different mineral powders have on the properties of self-compacting concrete (SCC) in order to obtain relations that make it possible to optimize their dosages for being used in precast concrete applications. Different combinations and contents of cement, mineral additions (active and inert), superplasticizers, and aggregates are considered. A new approach for determining the saturation point of superplasticizers is introduced. The fresh state performance was assessed by means of the following tests: slump flow, V-funnel, and J-ring. Concrete compressive strength values at different ages up to 56 days have been retained as representative of the materials’ performance in its hardened state. All these properties have been correlated with SCC proportioning. As a result, a number of recommendations for the precast concrete industry arise to design more stable SCC mixes with a reduced carbon footprint.

Individual Participant Data (IPD) Meta-analyses of Randomised Controlled Trials: Guidance on Their Use

Jayne Tierney and colleagues offer guidance on how to spot a well-designed and well-conducted individual participant data meta-analysis.

Summary Points 

• Systematic reviews are most commonly based on aggregate data extracted from publications or obtained from trial investigators. 

• Systematic reviews involving the central collection and analysis of individual participant data (IPD) usually are larger-scale, international, collaborative projects that can bring about substantial improvements to the quantity and quality of data, give greater scope in the analyses, and provide more detailed and robust results. 

• The process of collecting, checking, and analysing IPD is more complex than for aggregate data, and not all IPD meta-analyses are done to the same standard, making it difficult for researchers, clinicians, patients, policy makers, funders, and publishers to judge their quality. 

• Following our step-by-step guide will help reviewers and users of IPD meta-analyses to understand them better and recognise those that are well designed and conducted and so help ensure that policy, practice, and research are informed by robust evidence about the effects of interventions.

The use of patient experience survey data by out-of-hours primary care services: a qualitative interview study

Background English National Quality Requirements mandate out-of-hours primary care services to routinely audit patient experience, but do not state how it should be done.

Objectives We explored how providers collect patient feedback data and use it to inform service provision. We also explored staff views on the utility of out-of-hours questions from the English General Practice Patient Survey (GPPS).

Methods A qualitative study was conducted with 31 staff (comprising service managers, general practitioners and administrators) from 11 out-of-hours primary care providers in England, UK. Staff responsible for patient experience audits within their service were sampled and data collected via face-to-face semistructured interviews.

Results Although most providers regularly audited their patients’ experiences by using patient surveys, many participants expressed a strong preference for additional qualitative feedback. Staff provided examples of small changes to service delivery resulting from patient feedback, but service-wide changes were not instigated. Perceptions that patients lacked sufficient understanding of the urgent care system in which out-of-hours primary care services operate were common and a barrier to using feedback to enable change. Participants recognised the value of using patient experience feedback to benchmark services, but perceived weaknesses in the out-of-hours items from the GPPS led them to question the validity of using these data for benchmarking in its current form.

Conclusions The lack of clarity around how out-of-hours providers should audit patient experience hinders the utility of the National Quality Requirements. Although surveys were common, patient feedback data had only a limited role in service change. Data derived from the GPPS may be used to benchmark service providers, but refinement of the out-of-hours items is needed.

Using microbiological tracers to assess the impact of winter land use restrictions on the quality of stream headwaters in a small catchment.

Diverse land use activities can elevate risk of microbiological contamination entering stream headwaters. Spatially distributed water quality monitoring carried out across a 17km(2) agricultural catchment aimed to characterize microbiological contamination reaching surface water and investigate whether winter agricultural land use restrictions proved effective in addressing water quality degradation. Combined flow and concentration data revealed no significant difference in fecal indicator organism (FIO) fluxes in base flow samples collected during the open and prohibited periods for spreading organic fertilizer, while relative concentrations of Escherichia coli, fecal streptococci and sulfite reducing bacteria indicated consistently fresh fecal pollution reached aquatic receptors during both periods. Microbial source tracking, employing Bacteroides 16S rRNA gene markers, demonstrated a dominance of bovine fecal waste in river water samples upstream of a wastewater treatment plant discharge during open periods. This contrasted with responses during prohibited periods where human-derived signatures dominated. Differences in microbiological signature, when viewed with hydrological data, suggested that increasing groundwater levels restricted vertical infiltration of effluent from on-site wastewater treatment systems and diverted it to drains and surface water. Study results reflect seasonality of contaminant inputs, while suggesting winter land use restrictions can be effective in limiting impacts of agricultural wastes to base flow water quality.

Exploiting Human Resource Requirements to Infer Human Movement Patterns for Use in Modelling Disease Transmission Systems: An Example from Eastern Province, Zambia

In this research, an agent-based model (ABM) was developed to generate human movement routes between homes and water resources in a rural setting, given commonly available geospatial datasets on population distribution, land cover and landscape resources. ABMs are an object-oriented computational approach to modelling a system, focusing on the interactions of autonomous agents, and aiming to assess the impact of these agents and their interactions on the system as a whole. An A* pathfinding algorithm was implemented to produce walking routes, given data on the terrain in the area. A* is an extension of Dijkstra's algorithm with an enhanced time performance through the use of heuristics. In this example, it was possible to impute daily activity movement patterns to the water resource for all villages in a 75 km long study transect across the Luangwa Valley, Zambia, and the simulated human movements were statistically similar to empirical observations on travel times to the water resource (Chi-squared, 95% confidence interval). This indicates that it is possible to produce realistic data regarding human movements without costly measurement as is commonly achieved, for example, through GPS, or retrospective or real-time diaries. The approach is transferable between different geographical locations, and the product can be useful in providing an insight into human movement patterns, and therefore has use in many human exposure-related applications, specifically epidemiological research in rural areas, where spatial heterogeneity in the disease landscape, and space-time proximity of individuals, can play a crucial role in disease spread.

Factors that impact on the use of mechanical ventilation weaning protocols in critically ill adults and children: a qualitative-evidence synthesis

Background:
Prolonged mechanical ventilation is associated with a longer intensive care unit (ICU) length of stay and higher mortality. Consequently, methods to improve ventilator weaning processes have been sought. Two recent Cochrane systematic reviews in ICU adult and paediatric populations concluded that protocols can be effective in reducing the duration of mechanical ventilation, but there was significant heterogeneity in study findings. Growing awareness of the benefits of understanding the contextual factors impacting on effectiveness has encouraged the integration of qualitative evidence syntheses with effectiveness reviews, which has delivered important insights into the reasons underpinning (differential) effectiveness of healthcare interventions.

Objectives:
1. To locate, appraise and synthesize qualitative evidence concerning the barriers and facilitators of the use of protocols for weaning critically-ill adults and children from mechanical ventilation;

2. To integrate this synthesis with two Cochrane effectiveness reviews of protocolized weaning to help explain observed heterogeneity by identifying contextual factors that impact on the use of protocols for weaning critically-ill adults and children from mechanical ventilation;

3. To use the integrated body of evidence to suggest the circumstances in which weaning protocols are most likely to be used.

Search methods:
We used a range of search terms identified with the help of the SPICE (Setting, Perspective, Intervention, Comparison, Evaluation) mnemonic. Where available, we used appropriate methodological filters for specific databases. We searched the following databases: Ovid MEDLINE, Embase, OVID, PsycINFO, CINAHL Plus, EBSCOHost, Web of Science Core Collection, ASSIA, IBSS, Sociological Abstracts, ProQuest and LILACS on the 26th February 2015. In addition, we searched: the grey literature; the websites of professional associations for relevant publications; and the reference lists of all publications reviewed. We also contacted authors of the trials included in the effectiveness reviews as well as of studies (potentially) included in the qualitative synthesis, conducted citation searches of the publications reporting these studies, and contacted content experts.

We reran the search on 3rd July 2016 and found three studies, which are awaiting classification.

Selection criteria:
We included qualitative studies that described: the circumstances in which protocols are designed, implemented or used, or both, and the views and experiences of healthcare professionals either involved in the design, implementation or use of weaning protocols or involved in the weaning of critically-ill adults and children from mechanical ventilation not using protocols. We included studies that: reflected on any aspect of the use of protocols, explored contextual factors relevant to the development, implementation or use of weaning protocols, and reported contextual phenomena and outcomes identified as relevant to the effectiveness of protocolized weaning from mechanical ventilation.

Data collection and analysis:
At each stage, two review authors undertook designated tasks, with the results shared amongst the wider team for discussion and final development. We independently reviewed all retrieved titles, abstracts and full papers for inclusion, and independently extracted selected data from included studies. We used the findings of the included studies to develop a new set of analytic themes focused on the barriers and facilitators to the use of protocols, and further refined them to produce a set of summary statements. We used the Confidence in the Evidence from Reviews of Qualitative Research (CERQual) framework to arrive at a final assessment of the overall confidence of the evidence used in the synthesis. We included all studies but undertook two sensitivity analyses to determine how the removal of certain bodies of evidence impacted on the content and confidence of the synthesis. We deployed a logic model to integrate the findings of the qualitative evidence synthesis with those of the Cochrane effectiveness reviews.

Main results:
We included 11 studies in our synthesis, involving 267 participants (one study did not report the number of participants). Five more studies are awaiting classification and will be dealt with when we update the review.

The quality of the evidence was mixed; of the 35 summary statements, we assessed 17 as ‘low’, 13 as ‘moderate’ and five as ‘high’ confidence. Our synthesis produced nine analytical themes, which report potential barriers and facilitators to the use of protocols. The themes are: the need for continual staff training and development; clinical experience as this promotes felt and perceived competence and confidence to wean; the vulnerability of weaning to disparate interprofessional working; an understanding of protocols as militating against a necessary proactivity in clinical practice; perceived nursing scope of practice and professional risk; ICU structure and processes of care; the ability of protocols to act as a prompt for shared care and consistency in weaning practice; maximizing the use of protocols through visibility and ease of implementation; and the ability of protocols to act as a framework for communication with parents.

Authors' conclusions:
There is a clear need for weaning protocols to take account of the social and cultural environment in which they are to be implemented. Irrespective of its inherent strengths, a protocol will not be used if it does not accommodate these complexities. In terms of protocol development, comprehensive interprofessional input will help to ensure broad-based understanding and a sense of ‘ownership’. In terms of implementation, all relevant ICU staff will benefit from general weaning as well as protocol-specific training; not only will this help secure a relevant clinical knowledge base and operational understanding, but will also demonstrate to others that this knowledge and understanding is in place. In order to maximize relevance and acceptability, protocols should be designed with the patient profile and requirements of the target ICU in mind. Predictably, an under-resourced ICU will impact adversely on protocol implementation, as staff will prioritize management of acutely deteriorating and critically-ill patients.

Interventions to improve the appropriate use of polypharmacy in older people: a Cochrane systematic review

Objective: To summarise the findings of an updated Cochrane review of interventions aimed at improving the appropriate use of polypharmacy in older people. Design: Cochrane systematic review. Multiple electronic databases were searched including MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials (from inception to November 2013). Hand searching of references was also performed. Randomised controlled trials (RCTs), controlled clinical trials, controlled before-and-after studies and interrupted time series analyses reporting on interventions targeting appropriate polypharmacy in older people in any healthcare setting were included if they used a validated measure of prescribing appropriateness. Evidence quality was assessed using the Cochrane risk of bias tool and GRADE (Grades of Recommendation, Assessment, Development and Evaluation).
Setting: All healthcare settings. 
Participants: Older people (≥65 years) with ≥1 long-term condition who were receiving polypharmacy (≥4 regular medicines).
Primary and secondary outcome measures: Primary outcomes were the change in prevalence of appropriate polypharmacy and hospital admissions. Medication-related problems (eg, adverse drug reactions), medication adherence and quality of life were included as secondary outcomes.
Results: 12 studies were included: 8 RCTs, 2 cluster RCTs and 2 controlled before-and-after studies. 1 study involved computerised decision support and 11 comprised pharmaceutical care approaches across various settings. Appropriateness was measured using validated tools, including the Medication Appropriateness Index, Beers’ criteria and Screening Tool of Older Person’s Prescriptions (STOPP)/ Screening Tool to Alert doctors to Right Treatment (START). The interventions demonstrated a reduction in inappropriate prescribing. Evidence of effect on hospital admissions and medication-related problems was conflicting. No differences in health-related quality of life were reported.
Conclusions: The included interventions demonstrated improvements in appropriate polypharmacy based on reductions in inappropriate prescribing. However, it remains unclear if interventions resulted in clinically significant improvements (eg, in terms of hospital admissions). Future intervention studies would benefit from available guidance on intervention development, evaluation and reporting to facilitate replication in clinical practice.