Flexible, photonic films of surfactant-functionalized cellulose nanocrystals for pressure and humidity sensing

Most paints contain pigments that absorb light and fade over time. A robust alternative can be found in nature, where structural coloration arises from the interference of light with submicron features. Plant-derived, cellulose nanocrystals (CNCs) mimic these features by self-assembling into a cholesteric liquid crystal that exhibits structural coloration when dried. While much research has been done on CNCs in aqueous solutions, less is known about transferring CNCs to apolar solvents that are widely employed in paints. This study uses a common surfactant in agricultural and industrial products to suspend CNCs in toluene that are then dried into structurally colored films. Surprisingly, a stable liquid crystal phase is formed within hours, even with concentrations of up to 50 wt.-%. Evaporating the apolar CNC suspensions results in photonic films with peak wavelengths ranging from 660 to 920 nm. The resulting flexible films show increased mechanical strength, enabling a blue-shift into the visible spectrum with applied force. The films also act as humidity sensors, with increasing relative humidity yielding a red-shift. With the addition of a single surfactant, CNCs can be made compatible with existing production methods of industrial coatings, while improving the strength and responsiveness of structurally-colored films to external stimuli.Comment: 11 pages, 4 figure

Pathological and Immunocytochemical Changes in Chronic Calcium Oxalate Nephrolithiasis in the Rat

In the present study, we exposed rats to a crystal-inducing diet (CID) consisting of vitamin D3 and 0.5% ethylene glycol (EG), and we investigated histologically the kidney damage induced by the deposition of calcium oxalate (CaOx) crystals. After 28 days, 50 % of the animals had renal CaOx crystals, of which 60% also had small papillary stones. Most crystals were present in the cortex. The occurrence of these crystals coincided with morphological and cytochemical changes: glomerular damage, tubular dilatation and necrosis, and an enlargement of the interstitium. The number of epithelial and interstitial cells positive for the proliferating cell nuclear antigen (PCNA) was increased. Tamm-Horsfall protein (THP) was not only demonstrable in the thick ascending limb of the loop of Henle (TAL), but also frequently in glomeruli, in the proximal tubular epithelium, and in the papilla. In the lumen of the tubular system, it was associated with urinary casts. Reflection contrast microscopy (RCM) showed that the crystals were coated with a thin layer of THP. In spite of the high urinary oxalate concentrations, the above described cellular changes were not observed in CID-fed rats without renal crystals. We conclude, therefore, that in the kidney, the retained CaOx crystals rather than the urinary oxalate ions are responsible for the observed morphological and immunocytochemical changes

A systematic review of the quality and scope of economic evaluations in child oral health research

Background Economic evaluations provide policy makers with information to facilitate efficient resource allocation. To date, the quality and scope of economic evaluations in the field of child oral health has not been evaluated. Furthermore, whilst the involvement of children in research has been actively encouraged in recent years, the success of this movement in dental health economics has not yet been explored. This review aimed to determine the quality and scope of published economic evaluations applied to children’s oral health and to consider the extent of children’s involvement. Methods The following databases were searched: CINAHL, Cochrane Library, Econlit, EThOS, MEDLINE, NHS EED, OpenGrey, Scopus, Web of Science. Full economic evaluations, relating to any aspect of child oral health, published after 1997 were included and appraised against the Drummond checklist and the Consolidated Health Economic Evaluation Reporting Standards by a team of four calibrated reviewers. Data were also extracted regarding children’s involvement and the outcome measures used. Results Two thousand seven hundred fifteen studies were identified, of which 46 met the inclusion criteria. The majority (n = 38, 82%) were cost-effectiveness studies, with most focusing on the prevention or management of dental caries (n = 42, 91%). One study quantified outcomes in Quality Adjusted Life Years (QALYs), and one study utilised a child-reported outcome measure. The mean percentage of applicable Drummond checklist criteria met by the studies in this review was 48% (median = 50%, range = 0–100%) with key methodological weaknesses noted in relation to discounting of costs and outcomes. The mean percentage of applicable CHEERS criteria met by each study was 77% (median = 83%, range = 33–100%), with limited reporting of conflicts of interest. Children’s engagement was largely overlooked. Conclusions There is a paucity of high-quality economic evaluations in the field of child oral health. This deficiency could be addressed through the endorsement of standardised economic evaluation guidelines by dental journals. The development of a child-centred utility measure for use in paediatric oral health would enable researchers to quantify outcomes in terms of quality adjusted life years (QALYs) whilst promoting child-centred research

Lectin-Cytochemistry of Experimental Rat Nephrolithiasis

Lectin reactivity in epithelial apical cell coats of normal rat kidneys was compared to that from animals subjected to crystal inducing diets (CID). The aim was to see whether the absence of lectin reactivity in cell coats is related to intratubular calcium oxalate crystal retention. In normal rat kidneys, after a pre-embedding procedure, it was observed that at the ultrastructural level, reactivity was present but that the lectin specificity for the various parts of the nephron might have to be reconsidered. There was heterogeneity between the epithelial cells with respect to the presence of coat material in the tubular cell apices. Tubular epithelial cell apices from CID rats showed no obvious changes in lectin reactivity pattern. Lectin reactivity was present at the periphery of intratubular crystals but undetectable at true crystal attachment sites or reduced at cell apices in the vicinity of recently attached crystals or agglomerates. After a post-embedding reaction procedure, wheat-germ agglutinin (WGA)-lectin reactivity confirmed the presence of coat material in the cleft between cell apex and retained crystal at crystal-attachment sites. The WGA/Au-10 nm reaction products were also seen inside epithelial cells. WGA/Au-10 nm reaction products mark a crystal matrix component inside intratubular and re-tained crystals. A similar matrix was also marked by an α-osteopontin ( αOPN/Au-10 nm) reaction product

Can we detect ecosystem critical transitions and signals of changing resilience from paleo-ecological records?

Nonlinear responses to changing external pressures are increasingly studied in real-world ecosystems. However, as many of the changes observed by ecologists extend beyond the monitoring record, the occurrence of critical transitions, where the system is pushed from one equilibrium state to another, remains difficult to detect. Paleo-ecological records thus represent a unique opportunity to expand our temporal perspective to consider regime shifts and critical transitions, and whether such events are the exception rather than the rule. Yet, sediment core records can be affected by their own biases, such as sediment mixing or compression, with unknown consequences for the statistics commonly used to assess regime shifts, resilience, or critical transitions. To address this shortcoming, we developed a protocol to simulate paleolimnological records undergoing regime shifts or critical transitions to alternate states and tested, using both simulated and real core records, how mixing and compression affected our ability to detect past abrupt shifts. The smoothing that is built into paleolimnological data sets apparently interfered with the signal of rolling window indicators, especially autocorrelation. We thus turned to time-varying autoregressions (online dynamic linear models, DLMs; and time-varying autoregressive state-space models, TVARSS) to evaluate the possibility of detecting regime shifts and critical transitions in simulated and real core records. For the real cores, we examined both varved (annually laminated sediments) and non-varved cores, as the former have limited mixing issues. Our results show that state-space models can be used to detect regime shifts and critical transitions in some paleolimnological data, especially when the signal-to-noise ratio is strong. However, if the records are noisy, the online DLM and TVARSS have limitations for detecting critical transitions in sediment records

Reconceptualizing conservation

Early definitions of conservation focused largely on the end goals of protection or restoration of nature, and the various disciplinary domains that contribute to these ends. Conservation science and practice has evolved beyond being focused on just issues of scarcity and biodiversity decline. To better recognize the inherent links between human behaviour and conservation, “success” in conservation is now being defined in terms that include human rights and needs. We also know that who engages in conservation, and how, dictates the likelihood that conservation science will be embraced and applied to yield conservation gains. Here we present ideas for reconceptualizing conservation. We emphasize the HOW in an attempt to reorient and repurpose the term in ways that better reflect what contemporary conservation is or might aspire to be. To do so, we developed an acrostic using the letters in the term “CONSERVATION” with each serving as an adjective where C = co-produced, O = open, N = nimble, S = solutions-oriented, E = empowering, R = relational, V = values-based, A = actionable, T = transdisciplinary, I = inclusive, O = optimistic, and N = nurturing. For each adjective, we briefly describe our reasoning for its selection and describe how it contributes to our vision of conservation. By reconceptualizing conservation we have the potential to center how we do conservation in ways that are more likely to result in outcomes that benefit biodiversity while also being just, equitable, inclusive, and respectful of diverse rights holders, knowledge holders, and other actors. We hope that this acrostic will be widely adopted in training to help the next generation of conservation researchers and practitioners keep in mind what it will take to make their contributions effective and salient

The Canadian context for evidence-based conservation and environmental management

Canada has strong institutional capacity for science-based decision-making related to natural resource conservation and environmental management. Yet, the concept of using systematic reviews (conducted in accordance with established guidelines) to support evidence-based conservation and environmental management in Canada is in its infancy. Here we discuss the Canadian context for implementing more rigorous evidence-based approaches using systematic reviews. Of particular relevance to Canada is its vast size, broad diversity of ecosystems and heavy economic reliance on natural resources that vary widely in the type and scale of their environmental effects. These factors result in a wide variety of environmental monitoring needs over an extensive area that pose challenges to the scientific community charged with overseeing wise use of the environment. In addition, there are diverse and engaged user groups (e.g., hunters, trappers, fishers, bird watchers, foresters) and indigenous peoples that have constitutional rights to their natural resources. Traditional environmental knowledge is a complementary source of evidence in the Canadian environmental impact assessment process and therefore must be a part of evidence synthesis. Systematic reviews are not intended to replace local field studies, but rather have the opportunity to draw upon a broader suite of evidence that can be interfaced with local perspectives. The existing institutional structures in Canada could easily incorporate systematic reviews into their science advice and decision-making frameworks but to date, there are few examples of where this has occurred. Drawing on the expertise of a growing global collaboration for environmental evidence synthesis, Canadian institutions (federal, provincial and NGO) are poised to more broadly incorporate systematic reviews once their benefits are fully realized and the capacity to undertake such systematic reviews is fully developed. Systematic reviews offer a consolidated view of the available scientific literature on a given question. The results may offer significant value when working with stakeholders and decision makers contributing other sources of information to the question. For example, mechanisms to capture and integrate scientific knowledge with stakeholder and traditional knowledge may benefit from the scientific sources being filtered, interpreted and summarized for discussion. In other cases, wher

The estimation of patients' views on organizational aspects of a general dental practice by general dental practitioners: a survey study

Contains fulltext : 96429.pdf (publisher's version ) (Open Access)ABSTRACT: BACKGROUND: Considering the changes in dental healthcare, such as the increasing assertiveness of patients, the introduction of new dental professionals, and regulated competition, it becomes more important that general dental practitioners (GDPs) take patients' views into account. The aim of the study was to compare patients' views on organizational aspects of general dental practices with those of GDPs and with GDPs' estimation of patients' views. METHODS: In a survey study, patients and GDPs provided their views on organizational aspects of a general dental practice. In a second, separate survey, GDPs were invited to estimate patients' views on 22 organizational aspects of a general dental practice. RESULTS: For 4 of the 22 aspects, patients and GDPs had the same views, and GDPs estimated patients' views reasonably well: 'Dutch-speaking GDP', 'guarantee on treatment', 'treatment by the same GDP', and 'reminder of routine oral examination'. For 2 aspects ('quality assessment' and 'accessibility for disabled patients') patients and GDPs had the same standards, although the GDPs underestimated the patients' standards. Patients had higher standards than GDPs for 7 aspects and lower standards than GDPs for 8 aspects. CONCLUSION: On most aspects GDPs and patient have different views, except for social desirable aspects. Given the increasing assertiveness of patients, it is startling the GDP's estimated only half of the patients' views correctly. The findings of the study can assist GDPs in adapting their organizational services to better meet the preferences of their patients and to improve the communication towards patients

Recurrent respiratory tract infections (RRTI) in the elderly: A late onset mild immunodeficiency?

Transplantation and immunomodulatio

Long-term environmental change and shifts in the aquatic plant community of Jones Creek, Thousand Islands National Park, Ontario, Canada based on plant macrofossil analysis

Plant macrofossils and pollen were analyzed from sediment cores to identify long-term changes in the aquatic plant community of Jones Creek, Thousand Islands National Park, Ontario, Canada. Six sediment cores were recovered from Jones Creek in February 2014. One complete core and five top/bottom samples were analyzed for plant macrofossil abundance and diversity. Sediment analysis and 210Pb dating confirmed a productive wetland throughout the core, dating back beyond 1883 AD. Jones Creek is currently dominated by thick stands of cattails, particularly the hybrid white cattail (Typha x glauca Godr). The relative abundance of Typha pollen began to increase in the late nineteenth and early twentieth century, reaching a relative abundance of nearly 40% in the modern day surface sediment. Common macrofossils recovered from the sediment record included seeds of Carex, Schoenoplectus, Najas, and Eleocharis. There is evidence that community composition, as recorded by the macrofossil record, has shifted in Jones Creek in response to human activities. In particular there has been a reduction in sedge species between historical and present day conditions as the wetland shifted from a sedge dominated wet-meadow wetland to a cattail dominated system. The results of our study indicate that future restoration efforts should be directed towards reintroducing native sedge species that were present prior to major changes in land-use that occurred in the St. Lawrence region throughout the nineteenth and twentieth centuries