An environmentally benign antimicrobial nanoparticle based on a silver-infused lignin core

Silver nanoparticles have antibacterial properties, but their use has been a cause for concern because they persist in the environment. Here, we show that lignin nanoparticles infused with silver ions and coated with a cationic polyelectrolyte layer form a biodegradable and green alternative to silver nanoparticles. The polyelectrolyte layer promotes the adhesion of the particles to bacterial cell membranes and, together with silver ions, can kill a broad spectrum of bacteria, including Escherichia coli, Pseudomonas aeruginosa and quaternary-amine-resistant Ralstonia sp. Ion depletion studies have shown that the bioactivity of these nanoparticles is time-limited because of the desorption of silver ions. High-throughput bioactivity screening did not reveal increased toxicity of the particles when compared to an equivalent mass of metallic silver nanoparticles or silver nitrate solution. Our results demonstrate that the application of green chemistry principles may allow the synthesis of nanoparticles with biodegradable cores that have higher antimicrobial activity and smaller environmental impact than metallic silver nanoparticles

Service Robots in the Hospitality Industry: An Exploratory Literature Review

The service sector is changing drastically due the use of robotics and other technologies, such as Artificial Intelligence (AI), Internet of things (IoT), Big Data and Biometrics. Consequently, further research opportunities in the service industry domain are also expected. In light of the above, the purpose of this paper is to explore the potentialities and limitations of service robots in the hospitality industry. To this end, this paper uses a conceptual approach based on a literature review. As a result, we found that in contexts of high customer contact, service robots should be considered to perform standardized tasks due to social/emotional and cognitive/analytical complexity. The hospitality industry is therefore considered closely related to empathic intelligence, as the integration of service robots has not yet reached the desired stage of service delivery. In a seemingly far-fetched context of our reality, organizations will have to decide whether the AI will allow the complete replacement of humans with robots capable of performing the necessary cognitive and emotional tasks. Or investing in balanced capacities by integrating robot-human systems that seems a reasonable option these days.info:eu-repo/semantics/publishedVersio

A randomised controlled trial investigating motor skill training as a function of attentional focus in old age

BACKGROUND: Motor learning research has had little impact on clinical applications and rarely extended to research about how older adults learn motor skills. There is consistent evidence that motor skill performance and learning can be enhanced by giving learners instructions that direct their attention. The aim of this study was to test whether elderly individuals that receive an external focus instruction during training of dynamic balance skills would learn in a different manner compared to individuals that received an internal focus instruction. METHODS: This randomised trial included 26 older persons (81 +/- 6 years) that were training functional balance twice a week for the duration of 5 weeks. Learning outcomes were recorded after every training session. Weight shifting score and dynamic balance parameters (Biodex Balance System), components of the Extended Timed-Get-Up-and-Go test, five chair rises, and falls efficacy (FES-I) was assessed at baseline and post-intervention. RESULTS: Participation for training sessions was 94%. No differences between groups were found following 5 weeks of training for weight shifting score, dynamic balance index and dynamic balance time (p < 0.95, p = 0.16, p < 0.50), implying no learning differences between training groups. Extended Timed-Get-Up-and-Go components Sit-to-stand, p = .036; Gait initiation, p = .039; Slow down, stop, turnaround, and sit down, p = 0.011 and the Fes-I (p = 0.014) showed improvements for the total group, indicating that function improved compared to baseline. CONCLUSION: A 5-week balance training improved weight shifting scores and dynamic balance parameters as well as functional abilities. The observed improvements were independent from the type of attentional focus instructions. The findings provide support for the proposition of different motor learning principles in older adults compared to younger adults

Effect of sampling effort and sampling frequency on the composition of the planktonic crustacean assemblage: a case study of the river Danube

Although numerous studies have focused on the seasonal dynamics of riverine zooplankton, little is known about its short-term variation. In order to examine the effects of sampling frequency and sampling effort, microcrustacean samples were collected at daily intervals between 13 June and 21 July of 2007 in a parapotamal side arm of the river Danube, Hungary. Samples were also taken at biweekly intervals from November 2006 to May 2008. After presenting the community dynamics, the effect of sampling effort was evaluated with two different methods; the minimal sample size was also estimated. We introduced a single index (potential dynamic information loss; to determine the potential loss of information when sampling frequency is reduced. The formula was calculated for the total abundance, densities of the dominant taxa, adult/larva ratios of copepods and for two different diversity measures. Results suggest that abundances may experience notable fluctuations even within 1 week, as do diversities and adult/larva ratios

Of risks and regulations: how leading U.S. nanoscientists form policy stances about nanotechnology

Even though there is a high degree of scientific uncertainty about the risks of nanotechnology, many scholars have argued that policy-making cannot be placed on hold until risk assessments are complete (Faunce, Med J Aust 186(4):189–191, 2007; Kuzma, J Nanopart Res 9(1):165–182, 2007; O’Brien and Cummins, Hum Ecol Risk Assess 14(3):568–592, 2008; Powell et al., Environ Manag 42(3):426–443, 2008). In the absence of risk assessment data, decision makers often rely on scientists’ input about risks and regulation to make policy decisions. The research we present here goes beyond the earlier descriptive studies about nanotechnology regulation to explore the heuristics that the leading U.S. nanoscientists use when they make policy decisions about regulating nanotechnology. In particular, we explore the relationship between nanoscientists’ risk and benefit perceptions and their support for nanotech regulation. We conclude that nanoscientists are more supportive of regulating nanotechnology when they perceive higher levels of risks; yet, their perceived benefits about nanotechnology do not significantly impact their support for nanotech regulation. We also find some gender and disciplinary differences among the nanoscientists. Males are less supportive of nanotech regulation than their female peers and materials scientists are more supportive of nanotechnology regulation than scientists in other fields. Lastly, our findings illustrate that the leading U.S. nanoscientists see the areas of surveillance/privacy, human enhancement, medicine, and environment as the nanotech application areas that are most in need of new regulations

Evidence of Weak Habitat Specialisation in Microscopic Animals

Macroecology and biogeography of microscopic organisms (any living organism smaller than 2 mm) are quickly developing into fruitful research areas. Microscopic organisms also offer the potential for testing predictions and models derived from observations on larger organisms due to the feasibility of performing lab and mesocosm experiments. However, more empirical knowledge on the similarities and differences between micro- and macro-organisms is needed to ascertain how much of the results obtained from the former can be generalised to the latter. One potential misconception, based mostly on anedoctal evidence rather than explicit tests, is that microscopic organisms may have wider ecological tolerance and a lower degree of habitat specialisation than large organisms. Here we explicitly test this hypothesis within the framework of metacommunity theory, by studying host specificify in the assemblages of bdelloid rotifers (animals about 350 µm in body length) living in different species of lichens in Sweden. Using several regression-based and ANOVA analyses and controlling for both spatial structure and the kind of substrate the lichen grow over (bark vs rock), we found evidence of significant but weak species-specific associations between bdelloids and lichens, a wide overlap in species composition between lichens, and wide ecological tolerance for most bdelloid species. This confirms that microscopic organisms such as bdelloids have a lower degree of habitat specialisation than larger organisms, although this happens in a complex scenario of ecological processes, where source-sink dynamics and geographic distances seem to have no effect on species composition at the analysed scale

Association of waterpipe smoking and road traffic crashes

<p>Abstract</p> <p>Background</p> <p>The purpose of this research was to examine whether waterpipe smokers experience increased risk of motor vehicle crashes.</p> <p>Methods</p> <p>In a telephone survey, a random sample of Iranian drivers were asked to report their age, gender, vehicle age, whether their vehicles were equipped with anti-lock braking system (ABS), average daily drive time (DDT), whether they smoked cigarette or waterpipe, whether they had diabetes mellitus (DM), number of traffic crashes during the last calendar year and whether the crash involved a pedestrian or another vehicle.</p> <p>Results</p> <p>A total of 2070 motor vehicle owners with the mean age of 41.6 ± 11.45 were interviewed. The annual incidence of Road Traffic Crashes (RTC) was 14.9%; 14.0% involved a collision/s with other vehicles and 0.9% with pedestrians. There was an association between the RTC and male gender, DDT, being a cigarette smoker, being a waterpipe smoker and DM in univariable analysis. The association between RTC and being a waterpipe smoker and also cigarette smoker was significant in multivariable analysis after adjustment for DDT.</p> <p>Conclusions</p> <p>Being waterpipe and/or cigarette smoker and DDT were the independent predictors of the number of traffic crashes in Poisson regression model. If the increased risk of RTC among waterpipe or cigarette smokers is seen in other studies, it would be beneficial to promote tobacco cessation and control strategies through injury prevention initiatives.</p

Sh3pxd2b Mice Are a Model for Craniofacial Dysmorphology and Otitis Media

Craniofacial defects that occur through gene mutation during development increase vulnerability to eustachian tube dysfunction. These defects can lead to an increased incidence of otitis media. We examined the effects of a mutation in the Sh3pxd2b gene (Sh3pxd2bnee) on the progression of otitis media and hearing impairment at various developmental stages. We found that all mice that had the Sh3pxd2bnee mutation went on to develop craniofacial dysmorphologies and subsequently otitis media, by as early as 11 days of age. We found noteworthy changes in cilia and goblet cells of the middle ear mucosa in Sh3pxd2bnee mutant mice using scanning electronic microscopy. By measuring craniofacial dimensions, we determined for the first time in an animal model that this mouse has altered eustachian tube morphology consistent with a more horizontal position of the eustachian tube. All mutants were found to have hearing impairment. Expression of TNF-α and TLR2, which correlates with inflammation in otitis media, was up-regulated in the ears of mutant mice when examined by immunohistochemistry and semi-quantitative RT-PCR. The mouse model with a mutation in the Sh3pxd2b gene (Sh3pxd2bnee) mirrors craniofacial dysmorphology and otitis media in humans