Separation of natural from laboratory-grown diamond using time-gated luminescence imaging

A technique that expands on the surface luminescence imaging used in the DiamondView instrument has been developed at De Beers Group Technology, Maidenhead, UK. This provides an additional level of imaging information by way of separating prompt and delayed surface luminescence. The technique has the added benefit of quickly and easily distinguishing colorless or near-colorless natural diamond from laboratory-grown diamond. It can be applied when the identification of natural diamond is required in the study of single stones, multiples in batches, set jewelry, or in a fully automated process. The prompt and delayed luminescence characteristics of natural diamond are compared with a range of chemical vapor deposition (CVD) and high-pressure, high-temperature (HPHT) synthetic diamonds. Of significant interest are some of the less common CVD synthetic samples that have been observed in recent years. This article will summarize the luminescence observed in different diamond types, discuss its spectral characteristics, and serve as a useful reference when interpreting such luminescence images

Nitrogen fertiliser interactions with urine deposit affect nitrous oxide emissions from grazed grasslands

Cattle excreta deposited on grazed pastures are responsible for one fifth of the global anthropogenic nitrous oxide (N2O) emissions. One of the key nitrogen (N) sources is urine deposited from grazing animals, which contributes to very large N loadings within small areas. The main objective of this plot study was to establish whether the application of N fertiliser and urine deposit from dairy cows synergistically interacts and thereby increases N2O emissions, and how such interaction is influenced by the timing of application. The combined application of fertiliser (calcium ammonium nitrate) and urine significantly increased the cumulative N2O emissions as well as the N2O emission factor (EF) from 0.35 to 0.74 % in spring and from 0.26 to 0.52 % in summer. By contrast, EFs were lower when only fertiliser (0.31 % in spring, 0.07 % in summer) or urine was applied (0.33 % in spring, 0.28 % in summer). In autumn, N2O emissions were larger than in other seasons and the emissions from the combined application were not statistically different to those from either the separately applied urine or N fertiliser (EF ranging from 0.72 to 0.83, p-value < 0.05). The absence of significant synergistic effect could be explained by weather conditions, particularly rainfall during the three days prior to and after application in autumn. This study implies that the interactive effects of N fertilisation and urine deposit, as well as the timing of the application on N2O emission need to be taken into account in greenhouse gas emission inventories

Impact of fertiliser nitrogen formulation, and N stabilisers on nitrous oxide emissions in spring barley

The application of nitrogen (N) fertilisers to agricultural soils is a major source of nitrous oxide (N2O) emissions. The Intergovernmental Panel on Climate Change (IPCC) has set a default emission factor of 1% (EF1) for N fertiliser applied to managed agricultural soils. This value does not differentiate between different N fertiliser formulations or rates of N application. The objective of this field study under spring barley was to determine N2O EF’s for different N fertiliser formulations including urea and urea stabilised with the nitrification inhibitor dicyandiamide (DCD) and/or the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) and to evaluate their N2O loss abatement potential relative to calcium ammonium nitrate (CAN). The highest EF1 measured was 0.49% for CAN which was less than half the IPCC default value of 1%. While the urease inhibitor did not reduce emissions relative to CAN; the nitrification inhibitor significantly reduced emissions compared to CAN with EF1 as low as 0.00% for a typical spring barley site. There was no significant impact of CAN or urea application rate on EF1 but there was a significant negative relationship observed for urea in 2013. The study highlights the importance of generating higher Tier emission factors in terms of fertiliser type for use in national inventories

Carbon monoxide fluxes measured using the eddy covariance method from an intensively managed grassland in Ireland

Carbon monoxide (CO) is classed as a secondary greenhouse gas (GHG) as it can extend the lifetime of GHGs such as methane and ozone by reacting with hydroxyl (OH) radicals and thus controlling the oxidizing capacity of the atmosphere. CO fluxes were measured from a fertilized and grazed temperate grassland in south-east Ireland using a high frequency quantum cascade laser (QCL) and the eddy covariance method. Measurements were carried out in 2019 (12 months) and 2020 (10 months). In both datasets, a diurnal pattern was observed where CO fluxes peaked between 8 am and 6 pm, and between 8 pm and 2 am during the colder months of the year. Quality controlled CO flux data was gap-filled using a general additive model (GAM) that incorporated photosynthetic photon flux density (PPFD), air temperature, water-filled pore space (WFPS) and month of the year. Modelled CO emissions showed less divergence with measured CO fluxes in 2020 compared to 2019, suggesting that the environmental variables in the GAM were the predominant driver of CO emissions in 2020 but not in 2019. Cumulative CO emissions in 2019 and 2020 were 39.7 ± 147.1 mgCO–C per m2 per month and 31.5 ± 75.2 mgCO–C per m2 per month, respectively. While soils are typically considered a sink of CO, our results show that managed pastures can act as a source of CO and thus warrant further investigation into the implications CO may have on GHG dynamics from agricultural landscapes

Borehole Geologic Data for the 216-Z Crib Facilities, A Status of Data Assembled through the Hanford Borehole Geologic Information System (HBGIS)

The Pacific Northwest National Laboratory (PNNL) is assembling existing borehole geologic information to aid in determining the distribution and potential movement of contaminants released to the environment and to aid selection of remedial alternatives. This information is being assembled via the Hanford Borehole Geologic Information System (HBGIS), which is being developed as part of the Characterization of Systems Project, managed by PNNL, and the Remediation Decision Support Task of the Groundwater Remediation Project, managed by Fluor Hanford, Inc. The purpose of this particular study was to assemble the existing borehole geologic data pertaining to sediments underlying the 216-Z Crib Facilities and the Plutonium Finishing Plant Closure Zone. The primary objective for Fiscal Year 2006 was to assemble the data, complete log plots, and interpret the location of major geologic contacts for each major borehole in and around the primary disposal facilities that received carbon tetrachloride. To date, 154 boreholes located within or immediately adjacent to 19 of the 216-Z crib facilities have been incorporated into HBGIS. Borehole geologic information for the remaining three Z-crib facilities is either lacking (e.g. 216-Z-13, -14, and -15), or has been identified as a lesser priority to be incorporated at a later date

Mapping the rotational diffusion of fluorophores in cells with time-resolved wide-field fluorescence anisotropy imaging

CLEO/EUROPE ; EQEC European Quantum Electronics Conference, Munich ICM, Germany, 22-27 June, 2003N

Nutrition support practices and opinions toward gastrostomy use in pediatric bone marrow transplant centers : a national survey

Objective: Previous surveys have shown deviations in nutritional practices from international guidelines during bone marrow transplant (BMT). Guidelines recommend enteral nutrition first-line and nasogastric tubes are the mainstay for its provision. Gastrostomies provide an alternative, yet their use is less common. This national survey investigated nutrition support practices in pediatric allogeneic BMT centers and compared clinicians’ opinions on gastrostomy use. The aim of this study was to identify the national picture of nutritional support practices across pediatric allogeneic BMT centers, including use and opinions of dietitians, clinical nurse specialists, and physicians, toward gastrostomy feeding. Methods: An online survey was administered to 12 centers. The lead dietitian answered questions regarding nutritional counseling, screening, assessment, and interventions. Questions regarding current use, perceived advantages, and problems of gastrostomies were answered by the dietitian, lead clinical nurse specialist, and physician. Results: A 100% response rate was achieved from 12 centers (N = 36 clinicians). Nutritional counseling was provided in 92% of centers before and routinely throughout admission, 83% screened on and regularly throughout admission, 83% assessed nutritional status before transplant, and 92% used enteral nutrition first-line. Forty-two percent of the centers used gastrostomies. In those not using gastrostomies, 76% of clinicians felt some children should be offered a gastrostomy. Clinicians perceived less displacements (78%) and cosmetic appearance (69%) as the most common advantages of gastrostomies over nasogastric tubes. Risks associated with surgery (92%) and tube/stoma complications (58%) were the most common perceived problems. Conclusions: A similar approach was shown on many aspects of nutritional support. Gastrostomy use divided opinion with differences in use and perceived advantages, but agreement on potential complications. Despite their risks, clinicians wanted to use gastrostomies more. Placement requires careful consideration of the risks, benefits, and family preferences

Bifidobacterial biofilm formation is a multifactorial adaptive phenomenon in response to bile exposure

In the current study, we show that biofilm formation by various strains and species belonging to Bifidobacterium, a genus that includes gut commensals with reported health-promoting activities, is induced by high concentrations of bile (0.5% (w/v) or higher) and individual bile salts (20&nbsp;mM or higher), rather than by acid or osmotic stress. The transcriptomic response of a bifidobacterial prototype Bifidobacterium breve UCC2003 to such high bile concentrations was investigated and a random transposon bank of B. breve UCC2003 was screened for mutants that affect biofilm formation in order to identify genes involved in this adaptive process. Eleven mutants affected in their ability to form a biofilm were identified, while biofilm formation capacity of an insertional mutation in luxS and an exopolysaccharide (EPS) negative B. breve UCC2003 was also studied. Reduced capacity to form biofilm also caused reduced viability when exposed to porcine bile. We propose that bifidobacterial biofilm formation is an adaptive response to high concentrations of bile in order to avoid bactericidal effects of high bile concentrations in the gastrointestinal environment. Biofilm formation appears to be a multi-factorial process involving EPS production, proteins and extracellular DNA release, representing a crucial strategy in response to bile stress in order to enhance fitness in the gut environment

Systematic review of gastrostomy complications and outcomes in pediatric cancer and bone marrow transplant

Background Nutrition support is essential in children with cancer, including those undergoing bone marrow transplant (BMT), to reduce the risk of malnutrition and associated deleterious outcomes. Enteral nutrition is more commonly provided via nasogastric than gastrostomy tubes because of safety concerns with the latter in immunocompromised children. This systematic review investigated the incidence and type of complications and outcomes in pediatric cancer patients fed by gastrostomy. Methods Databases were searched for randomized and observational studies investigating the use of any gastrostomy device in children aged <18 years with any cancer diagnosis, including those undergoing BMT. Five cohort and 11 case series studies were included. Owing to clinical heterogeneity, meta-analyses were not performed. Results Quality of evidence varied, with five studies judged at serious risk of bias and poor quality; however, the remaining 11 were considered to range from moderate to good quality. Across studies, 54.6% of children developed one or more complications, of which 76.6% were classified as minor, 23.4% major. The most frequent complications included inflammation (52% of episodes), infection (42.1%), leakage (22.3%), and granuloma (21%). Evidence regarding infection rates in cancer/BMT patients compared with other disease states was inconclusive. Gastrostomy feeding was associated with improvement or stabilization of nutrition status in 77%–92.7% of children. Conclusion Gastrostomy feeding in this population is relatively safe and effective in stabilizing or improving nutrition status throughout treatment. Complications are frequent but mostly minor. Placement requires careful consideration of the complications, benefits, nutrition risk and status at diagnosis, and quality of life