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All data are spatial. Try to think of a piece of data that is not spatial, and we bet with a little more thought, you could come up with a spatial characteristic of those data! Perhaps the name of a historic figure? That name has a provenance … it was given in a particular place, and the person may have lived in one or more places, and moved about the surface of the Earth according to some pattern. And the name itself (if written) has a length measured in number of letters, and it has shapes and sizes that affect its perception by others, much like the spatial elements of a map communicate something to its audience.
Antibiotic-resistant organism (ARO) colonization rates in skilled nursing facilities (NFs) are high; hand hygiene is crucial to interrupt transmission. We aimed to determine factors associated with hand hygiene adherence in NFs and to assess rates of ARO acquisition among healthcare personnel (HCP).
HCP were observed during routine care at 6 NFs. We recorded hand hygiene adherence, glove use, activities, and time in room. HCP hands were cultured before and after patient care; patients and high-touch surfaces were cultured. HCP activities were categorized as high-versus low-risk for self-contamination. Multivariable regression was performed to identify predictors of hand hygiene adherence.
We recorded 385 HCP observations and paired them with cultures performed before and after patient care. Hand hygiene adherence occurred in 96 of 352 observations (27.3%) before patient care and 165 of 358 observations (46.1%) after patient care. Gloves were worn in 169 of 376 observations (44.9%). Higher adherence was associated with glove use before patient care (odds ratio [OR], 2.55; 95% confidence interval [CI], 1.44–4.54) and after patient care (OR, 3.11; 95% CI, 1.77–5.48). Compared with nurses, certified nurse assistants had lower hand hygiene adherence (OR, 0.31; 95% CI, 0.15–0.67) before patient care and physical/occupational therapists (OR, 0.22; 95% CI, 0.11–0.44) after patient care. Hand hygiene varied by activity performed and time in the room. HCP hands were contaminated with AROs in 35 of 385 cultures of hands before patient care (0.9%) and 22 of 350 cultures of hands after patient care (6.3%).
Hand hygiene adherence in NFs remain low; it is influenced by job title, type of care activity, and glove use. Hand hygiene programs should incorporate these unique care and staffing factors to reduce ARO transmission.
The modern antiquities market uses radiocarbon (14C) dating to screen for forged objects. Although this fact shows the potential and power of the method, the circumstances where it is applied can be questionable and call for our attention. Here we present an outline of a call to radiocarbon laboratories for due diligence and best practice approaches to the analysis of antique objects requested by non-research clients.
Although radiocarbon (14C) dating is commonly used for archeological music instruments, little research has been conducted on modern instruments (16th–19th centuries). New technology, based on the Mini Carbon Dating System (MICADAS), enables some of the recurring challenges (e.g. sampling size) to be circumvented and paves the way for a new field of investigation. We here address the Indian instrumentarium, about which very little is known. We investigate the making and the restoration phases of two vina, a kinnari vina (E.1444), and a rudra vina or bin (E.997.24.1). By comparing 14C measurements made on several samplings of elements of the instruments with museological information, we were able to specify a unique calibrated interval of ages [1666 AD–1690 AD] for the kinnari vina, with a restoration phase [1678 AD–1766 AD] for the upper nut. The bin is likely attributed to the [1650 AD–1683 AD] interval.
Manipulation of an array of surface droplets organised in an ordered structure turns out to be of immense consequence in a wide variety of applications ranging from photonics, near field imaging and inkjet printing on the one hand to bio-molecular analysis and DNA sequencing on the other. While evaporation of a single isolated sessile droplet has been well studied, the collective evaporative dynamics of an ordered array of droplets on a solid substrate remains elusive. Physically, the closed region between the centre and side droplets in the ordered array reduces the mobility of the diffusing vapour, resulting in its accumulation along with enhanced local concentration and a consequent increment in the lifetime of the centre droplet. Here, we present a theoretical model to account for evaporation lifetime scaling in closely placed ordered linear droplet arrays. In addition, the present theory predicts the limiting cases of droplet interaction; namely, critical droplet separation for which interfacial interaction ceases to exist and minimum possible droplet separation (droplets on the verge of coalescence) for which the droplet system achieves maximum lifetime scaling. Further experimental evidence demonstrates the applicability of the present scaling theory to extended dimensions of the droplet array, generalising our physical conjecture. It is also worth noting that the theoretical time scale is applicable across a wide variety of drop–substrate combinations and initial droplet volumes. We also highlight that the scaling law proposed here can be extended seamlessly to other forms of confinement such as an evaporating droplet inside a mini-channel, as encountered in countless applications ranging from biomedical engineering to surface patterning.
Novel approaches to improving disaster response have begun to include the use of big data and information and communication technology (ICT). However, there remains a dearth of literature on the use of these technologies in disasters. We have conducted an integrative literature review on the role of ICT and big data in disasters. Included in the review were 113 studies that met our predetermined inclusion criteria. Most studies used qualitative methods (39.8%, n=45) over mixed methods (31%, n=35) or quantitative methods (29.2%, n=33). Nearly 80% (n=88) covered only the response phase of disasters and only 15% (n=17) of the studies addressed disasters in low- and middle-income countries. The 4 most frequently mentioned tools were geographic information systems, social media, patient information, and disaster modeling. We suggest testing ICT and big data tools more widely, especially outside of high-income countries, as well as in nonresponse phases of disasters (eg, disaster recovery), to increase an understanding of the utility of ICT and big data in disasters. Future studies should also include descriptions of the intended users of the tools, as well as implementation challenges, to assist other disaster response professionals in adapting or creating similar tools. (Disaster Med Public Health Preparedness. 2019;13:353–367)
The purpose of the current study was to examine associations of individual and aggregated screen-based behaviours, and total sitting time, with healthy and unhealthy dietary intakes among adolescents.
Cross-sectional study of adolescents. Participants self-reported durations of television viewing, computer use, playing electronic games (e-games), total sitting time, daily servings of fruits and vegetables, and frequency of consumption of sugar-sweetened beverages (SSB), diet beverages, fast foods and discretionary snacks. Logistic regression models were conducted to identify associations of screen-based behaviours, total screen time and total sitting time with dietary intakes.
Adolescents (n 939) in School Year 11 (mean age 16·8 years).
The results showed that watching television (≥2 h/d) was positively associated with consuming SSB and diet beverages each week and consuming discretionary snacks at least once daily, whereas computer use (≥2 h/d) was inversely associated with daily fruit and vegetable intake and positively associated with weekly fast-food consumption. Playing e-games (any) was inversely associated with daily vegetable intake and positively associated with weekly SSB consumption. Total screen (≥2 h/d) and sitting (h/d) times were inversely associated with daily fruit and vegetable consumption, with total screen time also positively associated with daily discretionary snack consumption and weekly consumption of SSB and fast foods.
Individual and aggregated screen-based behaviours, as well as total sitting time, are associated with a number of indicators of healthy and unhealthy dietary intake. Future research should explore whether reducing recreational screen time improves adolescents’ diets.
Nitrogenous compounds of soil organic matter constitute a major N reservoir on Earth. Both the world food protein supply produced by agriculture and the global contamination by reactive nitrogen species rely on the dynamics of these compounds. To investigate their dynamics, we used both natural 13C labeling and accelerator mass spectrometry (AMS) 14C dating of the α-carboxyl amino carbon, which is specific of the amino acid fraction that was extracted from bulk soil organic matter by ninhydrin hydrolysis. We applied this isotopic approach to investigate the age of carboxyl carbon in a maize-cultivated Cambisol chronosequence. Based on a few measurements, we demonstrate the feasibility of this new compound-specific method of investigation of soil carbon dynamics. We show that soil organic matter amino acids can be split into two very distinct dynamic compartments: the majority having a mean age of a few years and a minority having a mean carbon age of several millennia. The latter fraction can be either strongly stabilized in soils, or can arise from microbial utilization of old carbon resources, as predicted by the priming effect theory.
The IntCal09 and Marine09 radiocarbon calibration curves have been revised utilizing newly available and updated data sets from 14C measurements on tree rings, plant macrofossils, speleothems, corals, and foraminifera. The calibration curves were derived from the data using the random walk model (RWM) used to generate IntCal09 and Marine09, which has been revised to account for additional uncertainties and error structures. The new curves were ratified at the 21st International Radiocarbon conference in July 2012 and are available as Supplemental Material at www.radiocarbon.org. The database can be accessed at http://intcal.qub.ac.uk/intcal13/.
Dating sedimentary series spanning the past few tens of thousands of years is often problematic due to the quality of radiocarbon data obtained from organic matter (OM), including bulk OM. This problem recently arose when establishing the chronology of a sediment infill at the Sarliève paleolake (French Massif Central). In the studied section of the cores that covers the Neolithic, Ruppia seeds yielded consistent ages for the lower part (7195 ± 75 to 6050 ± 60 yr BP). A reservoir age of 82 ± 42 14C yr was estimated through the comparison of ages derived from charcoal, Ruppia seeds, and charophyte oogonia sampled on a single level. The upper part of the cores lacks macrofossils and bulk OM dating yields unusable data because of a significant contribution of aged OM derived from the Oligocene substratum in the catchment. We therefore performed dating of lipids extracted from the sediments. The age of the lipids was 2880 ± 30 yr BP near the top of the section, i.e. much younger than the age estimated from previous correlations based on pollen assemblages. These new data call into question previous paleoenvironmental interpretations. The combined dating methodology used for the Neolithic series of Sarliève is a rather uncommon approach that may help to refine chronologies of Holocene sedimentary series.
Microbial mats (kopara in Polynesian) that develop in shallow brackish to hypersaline ponds on the rims of atolls were investigated for their accumulation process and rate. Two sequences of ∼30-cm-deep kopara, composed of 7 and 5 layers distinguished by their colors and sedimentological facies were collected in 1996 from the Tetiaroa atoll, French Polynesia. The combination of radiocarbon activity measurements on both organic and carbonate constituents, reservoir effect estimation, and comparison with the Southern Hemisphere atmospheric bomb-peak 14C record allowed us to establish a fine chronology of the layer successions documenting the mode of formation, erosion, and restoration of these microbial mat deposits.
The aim of this study is to directly radiocarbon date pottery from prehistoric rock-art shelters in the Tassili n'Ajjer (central Sahara). We used a combined geochemical and microscopic approach to determine plant material in the pottery prior to direct 14C dating. The ages obtained range from 5270 ± 35 BP (6276–5948 cal BP) to 8160 ± 45 BP (9190–9015 cal BP), and correlate with the chronology derived from pottery typology. Our results document the transition from pre-Pastoral to Pastoral contexts, dated to the early-mid Holocene transition, and confirm that vegetal temper in pottery can provide reliable 14C ages within Saharan contexts.
High-quality data from appropriate archives are needed for the continuing improvement of radiocarbon calibration curves. We discuss here the basic assumptions behind 14C dating that necessitate calibration and the relative strengths and weaknesses of archives from which calibration data are obtained. We also highlight the procedures, problems, and uncertainties involved in determining atmospheric and surface ocean 14C/12C in these archives, including a discussion of the various methods used to derive an independent absolute timescale and uncertainty. The types of data required for the current IntCal database and calibration curve model are tabulated with examples.