The bactericidal effects of negative ions in air

The use of negative ions to improve indoor air quality has attracted increasing attention in recent years. Although the physical action of air ionisers is accepted, there is still debate over their apparent biocidal action. A recent clinical trial in an intensive care unit suggested that air ionisers may have a role in reducing the transmission of infection in healthcare environments1 and several authors have reported that ions inhibit the growth of a range of microorganisms. A further understanding of this process was gained through bench scale experiments exposing sessile cultures to positive and negative ions2. The aim of the work presented here was to follow on from the bench scale experiments to investigate the efficacy of negative ions with aerosolised microorganisms

Fire Hazard Analysis of Technical Area 53 Building 1, Los Alamos National Lab

This is an analysis of a 1970’s vintage building as it is compared to current building codes and standards. The purpose of this document is to assess if the current, as found construction of an existing building could achieve the sometimes more restrictive modern building codes. Both a prescriptive analysis and a performance-based analysis were completed to verify life-safety concerns and criteria as well as construction criteria. The prescriptive analysis compared existing, as found construction to current codes and standards while the prescriptive analysis used modern fire modeling techniques to see how likely fire scenarios would challenge the structure, if at all

Invariant higher-order variational problems II

Motivated by applications in computational anatomy, we consider a second-order problem in the calculus of variations on object manifolds that are acted upon by Lie groups of smooth invertible transformations. This problem leads to solution curves known as Riemannian cubics on object manifolds that are endowed with normal metrics. The prime examples of such object manifolds are the symmetric spaces. We characterize the class of cubics on object manifolds that can be lifted horizontally to cubics on the group of transformations. Conversely, we show that certain types of non-horizontal geodesics on the group of transformations project to cubics. Finally, we apply second-order Lagrange--Poincar\'e reduction to the problem of Riemannian cubics on the group of transformations. This leads to a reduced form of the equations that reveals the obstruction for the projection of a cubic on a transformation group to again be a cubic on its object manifold.Comment: 40 pages, 1 figure. First version -- comments welcome

Effects of a novel bicycle saddle on symptoms and comfort in cyclists

Background. While the bicycle frame and other parts of the bicycle have undergone many improvements, the bicycle saddle has remained relatively unchanged since it was first designed more than 100 years ago. Given the number and range of cycling injuries believed to result from the saddle, this is surprising. This study investigated the effects of a novel bicycle saddle on saddle-related comfort and symptoms during cycling.Method. Eleven competitive or recreational cyclists, 6 females and 5 males, performed three 2-hour stationary cycle rides in the laboratory, using their personal bicycles. Ride 1 was performed using the standard bicycle saddle and rides 2 and 3 using the novel bicycle saddle. Subjects reported saddle comfort rating scores (SC) while using the different saddles. Subjects also completed a questionnaire evaluating saddle symptoms (SS) when using either the conventional or the novel bicycle saddle during daily cycling.Results. The most common saddle-related medical complaint with chronic use of the conventional saddle was painful pubic bones, with or without chafing. Others were severe chafing, saddle sores, chafing and back pain, and painful pubic bones associated with a loss of feeling in the pelvic area. The mean SS rating score during the 2-hour laboratory ride was significantly less for the novel saddle (11.6 ± 1.2 versus 19.1 ± 3.2 arbitrary units, P < 0.01). Similarly the mean SC score was significantly lower for the novel saddle (36.2 ± 10.5 v. 54.7 ± 11.2 arbitrary units). Values for both SC scores were similar for rides 2 and 3. On completion of the trial all subjects indicated that they would continue to use the novel saddle in preference to the conventional saddle. Three months later 9 subjects (82%) reported continued use of this saddle in preference to the conventional saddle.Conclusion. These results show conclusively that this novel bicycle saddle: (i) significantly reduced reported symptoms during daily cycling compared with the conventionally designed cycling saddle; (ii) significantly improved saddle comfort during 2-.hour cycles in the laboratory, such that (iii) when given the option the majority (82%) of the subjects chose to use this saddle 3 months later. Furthermore, the beneficial effects of the novel saddle were apparent during its first use, suggesting that the novel saddle is effective because the design is anatomically correct

Maternal Smoking in Pregnancy: Do the Effects on Innate (Toll-Like Receptor) Function Have Implications for Subsequent Allergic Disease?

Subtle increases in immaturity of immune function in early infancy have been implicated in the rising susceptibility to allergic disease, particularly relative impairment of type 1 interferon (IFN)-γ responses in the neonatal period. Although genetic predisposition is a clear risk factor, the escalating rates of allergic disease in infancy suggest that environmental factors are also implicated. We previously showed that maternal smoking in pregnancy may impair neonatal IFN-γ responses. Our more recent studies now indicate that this common avoidable toxic exposure is also associated with attenuation of innate immune function, with attenuated Toll-like receptor (TLR)-mediated microbial responses (including TLR-2, -3, -4, and -9 responses). Most notably, the effects were more marked if the mothers were also allergic. In this review, we discuss the significance of these observations in the context of the emerging hypothesis that variations in TLR function in early life may be implicated in allergic propensity. There is now growing evidence that many of the key pathways involved in subsequent T-cell programming and regulation (namely, antigen-presenting cells and regulatory T cells) rely heavily on microbe-driven TLR activation for maturation and function. Factors that influence the function and activity of these innate pathways in early life may contribute to the increasing predisposition for allergic disease. Although "cleaner" environments have been implicated, here we explore the possibility that other common environmental exposures (such as maternal smoking) could also play a role.</p

Cross-fostering and Parent-offspring Responses in Cichlasoma citrinellum (Pisces, Cichlidae)

Previous studies of parent-young interactions in cichlid fish have established some of the details of such relations, but have raised, or left unanswered many questions. In particular, there are questions as to the recognition of parents and young by each other, and to what extent learning might be involved in such recognition. Based on observations of exchanges of parents between families of Cichlasoma citrinellum, we suggest that parents learn to recognize young during each parental cycle. They appear to have a moderately short term memory for recognition of young, and accept young corresponding to this memory. Parental fish accept conspecific fry younger than, or the same age, but not those older than their own. Successive presentations of young fry maintained parental behavior for much longer than normal. Changes in color pattern, and some aspects of parental behavior are described

‘My Husband is Interested in War Generally’: gender, family history and the emotional legacies of total war

In the autumn of 2014, as Britain embarked on four years of activities to commemorate and mark the centenary of the First World War, the Mass Observation project asked its panellists to reflect on their feelings about the war. Over 180 people responded, writing about their family involvement in the war, about their thoughts and feelings on Remembrance Sunday 2014, and about popular representations of the war in the early twenty-first century. This article examines some of these responses, considering the extent to which gender and age shaped not only the panellists’ stated relationship to the centenary of the war, but also the language with which they expressed this relationship. It draws on ideas from the ‘emotional turn’ in historical studies to argue that older women, who often had a personal memory of the lived legacies of the war, drew on a particularly expressive repertoire to convey both an empathy with the men and women whose lives were shaped by the First World War, and to argue for a particular moral position with regard to warfare. These empathetic responses, which the article argues have much in common with family histories of the war, should be taken seriously by historians who examine the cultural memory of the war and who are often keen to dismiss the widespread sense of the war as a tragic blunder

Participants' views on constraints and opportunities in the development of diamond tourism in Yellowknife, Northwest Territories

Diamond tourism is an experience that is currently being developed in Yellowknife, Northwest Territories, Canada. Ideally, diamond tourism engages tourists in an educational experience about the diamond mining process, starting with extraction of the rough diamond through to the cutting, the polishing, and, finally, the purchasing stage