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A theoretically based relationship for the Darcy–Weisbach friction factor
for rough-bed open-channel flows is derived and discussed. The derivation procedure is based on the double averaging (in time and space) of the Navier–Stokes equation followed by repeated integration across the flow. The obtained relationship explicitly shows that the friction factor can be split into at least five additive components, due to: (i) viscous stress; (ii) turbulent stress; (iii) dispersive stress (which in turn can be subdivided into two parts, due to bed roughness and secondary currents); (iv) flow unsteadiness and non-uniformity; and (v) spatial heterogeneity of fluid stresses in a bed-parallel plane. These constitutive components account for the roughness geometry effect and highlight the significance of the turbulent and dispersive stresses in the near-bed region where their values are largest. To explore the potential of the proposed relationship, an extensive data set has been assembled by employing specially designed large-eddy simulations and laboratory experiments for a wide range of Reynolds numbers. Flows over self-affine rough boundaries, which are representative of natural and man-made surfaces, are considered. The data analysis focuses on the effects of roughness geometry (i.e. spectral slope in the bed elevation spectra), relative submergence of roughness elements and flow and roughness Reynolds numbers, all of which are found to be substantial. It is revealed that at sufficiently high Reynolds numbers the roughness-induced and secondary-currents-induced dispersive stresses may play significant roles in generating bed friction, complementing the dominant turbulent stress contribution.
Gut cell losses contribute to overall feed efficiency due to the energy requirement for cell replenishment. Intestinal epithelial cells are sloughed into the intestinal lumen as digesta passes through the gastrointestinal tract, where cells are degraded by endonucleases. This leads to fragmented DNA being present in faeces, which may be an indicator of gut cell loss. Therefore, measuring host faecal DNA content could have potential as a non-invasive marker of gut cell loss and result in a novel technique for the assessment of how different feed ingredients impact upon gut health. Faecal calprotectin (CALP) is a marker of intestinal inflammation. This was a pilot study designed to test a methodology for extracting and quantifying DNA from pig faeces, and to assess whether any differences in host faecal DNA and CALP could be detected. An additional aim was to determine whether any differences in the above measures were related to the pig performance response to dietary yeast-enriched protein concentrate (YPC). Newly weaned (∼26.5 days of age) Large White × Landrace × Pietrain piglets (8.37 kg ±1.10, n = 180) were assigned to one of four treatment groups (nine replicates of five pigs), differing in dietary YPC content: 0% (control), 2.5%, 5% and 7.5% (w/w). Pooled faecal samples were collected on days 14 and 28 of the 36-day trial. Deoxyribonucleic acid was extracted and quantitative PCR was used to assess DNA composition. Pig genomic DNA was detected using primers specific for the pig cytochrome b (CYTB) gene, and bacterial DNA was detected using universal 16S primers. A pig CALP ELISA was used to assess gut inflammation. Dietary YPC significantly reduced feed conversion ratio (FCR) from weaning to day 14 (P<0.001), but not from day 14 to day 28 (P = 0.220). Pig faecal CYTB DNA content was significantly (P = 0.008) reduced in YPC-treated pigs, with no effect of time, whereas total faecal bacterial DNA content was unaffected by diet or time (P>0.05). Faecal CALP levels were significantly higher at day 14 compared with day 28, but there was no effect of YPC inclusion and no relationship with FCR. In conclusion, YPC reduced faecal CYTB DNA content and this correlated positively with FCR, but was unrelated to gut inflammation, suggesting that it could be a non-invasive marker of gut cell loss. However, further validation experiments by an independent method are required to verify the origin of pig faecal CYTB DNA as being from sloughed intestinal epithelial cells.
Conventional selected area diffraction patterns as obtained in the TEM present difficulties for identification of materials such as asbestifonn minerals, although diffraction data is considered to be one of the preferred methods for making this identification. The preferred orientation of the fibers in each field of measurement, and the spotty patterns that are obtained, do not readily lend themselves to measurement of the integrated intensity values for each dspacing, and even the d-spacings may be hard to determine precisely because the true center location for the broken rings requires estimation. To overcome these problems, we have implemented an automatic method for diffraction pattern measurement. It automatically locates the center of patterns with high precision, measures the radius of each ring of spots in the pattern, and integrates the density of spots in that ring.
OBJECTIVES/SPECIFIC AIMS: The Life’s Simple 7 (LS7) metric was created by the American Heart Association with the goal of educating the public on seven modifiable factors that contribute to heart health. While it is well documented that these ideal health behaviors lower risk of cardiovascular disease (CVD) in the general population, the association between the LS7 ideal health metrics and end stage renal disease (ESRD) risk has not been examined in a lower socioeconomic population at high risk for both ESRD and CVD. Our objective is to examine the association between the LS7 score and incident ESRD in a cohort of white and black men and women in the southeastern US, where rates of CVD and ESRD are high. METHODS/STUDY POPULATION: The Southern Community Cohort Study recruited ~86,000 low-income blacks and whites in the southeastern US (2002-2009). Utilizing a nested case-control design, our analysis included 1628 incident cases of ESRD identified via linkage of the cohort with the United States Renal Data System (USRDS) from January 1, 2002 to March 31, 2015. Controls (n = 4884) were individually matched 3:1 with ESRD cases based on age, sex, and race. Demographic, medical, and lifestyle information were obtained via baseline questionnaire. The AHA definitions for ideal health were used for non-smoking (never or quit >12 months), body mass index (BMI<25kg/m2) and physical activity (>75 min/week of vigorous physical activity or >150min/week of moderate/vigorous activity). Modified definitions were used for consuming a healthy diet [Healthy Eating Index (HEI10) score>70] and for blood pressure, fasting plasma glucose, and total cholesterol, based on self-reported no history of diagnosis of hypertension, diabetes, and hypercholesterolemia, respectively. The number of ideal health parameters were summed to generate the LS7 score, which ranged from 0-7 with higher scores indicating more ideal health. Adjusted odds ratios (95% confidence intervals) for incident ESRD associated with LS7 score were calculated using conditional logistic regression models, adjusting for income and education. The SCCS ESRD case-cohort dataset will be available by TS 2019 and analyses will be completed to adjust for baseline estimated glomerular filtration rate (eGFR) as a marker of kidney function and to examine whether eGFR modifies the relationship between LS7 and incident ESRD. RESULTS/ANTICIPATED RESULTS: At baseline, mean age was 54 years, 55% (3600) of participants were women, and 87% (5656) were black. A total of 58% (943) of ESRD cases were non-smokers compared to 54% (2633) of controls. ESRD cases had higher prevalence of BMI>25 kg/m2 (81% vs. 74%), hypertension (84% vs. 59%), hypercholesterolemia (48% vs. 34%), and diabetes (66% vs. 22%) compared to controls. A total of 18% (839) of controls and 12% (194) of ESRD cases met ideal exercise recommendations, and 20% of either cases (302) or controls (916) had a HEI10 score above 70. The median LS7 score for controls and ESRD cases was 3 and 2, respectively, and 17% (983) of participants had a low score (0-1) while 2% (105) met 6 or 7 ideal health metrics. Higher LS7 score was associated with lower odds of ESRD (P-trend<0.001). Participants with LS7 score >3 (above median) had 75% reduced odds of ESRD (OR 0.25; 95% CI 0.22, 0.29) compared to those with a score of 2 or less. DISCUSSION/SIGNIFICANCE OF IMPACT: In the SCCS population, the presence of any 3 or more ideal health behaviors is associated with reduced odds of developing ESRD. The components of the LS7 represent important modifiable risk factors that may be targets for future interventions driven by the patient. The attributable risk due to each factor is needed to dissect which ideal behaviors are the most beneficial.
1. Introduction. On recent occasions papers have been presented concerned with the problem of solving a system of linear congruences. Apparently the authors were not aware that this problem was solved very neatly and completely a long time ago by H. J. S. Smith (5; 6).
Objectives: To examine academic performance in dystrophinopathy as a function of dystrophin gene mutation position as well as intellectual function, executive skills, socioeconomic status (SES), behavior, and physical ability. Methods: In a cross-sectional study, boys with dystrophinopathy (ages 5–17; n=50) completed tests of academics (Woodcock-Johnson-III: spelling, reading, calculation and total scores), executive functioning (selective attention/inhibitory control, set shifting, working memory, and processing speed), single word comprehension and nonverbal reasoning. Motor skills were assessed and parents provided demographic information and child behavioral assessments. Dystrophin gene mutation positions were dichotomized into groups (upstream versus downstream of exon 43, location of isoforms previously linked to intellectual impairment). Genetic mutation groups were compared on measures of academic achievement, and multiple regression analyses examined unique and joint contributions of executive skills, intelligence quotient (IQ), SES, motor abilities, behavior, and mutation positions to academic outcomes. Results: Academic performance was slightly, yet significantly, lower than IQ and varied as a function of dystrophin gene position, wherein boys possessing the downstream mutation exhibited greater impairment than boys with the upstream mutation. Digit span forward (indexing verbal span), but no other measure of executive function, contributed significant variance to total academic achievement, spelling and calculation. Conclusions: Weak academic performance is associated with dystrophinopathy and is more common in downstream mutations. A specific deficit in verbal span may underlie inefficiencies observed in children with dystrophinopathy and may drive deficits impacting academic abilities. (JINS, 2018, 24, 928–938)
The majority of lambs in the United States are born from late winter to early spring and pregnant ewes are generally sheared in the last third of pregnancy. Although there are benefits to shearing before parturition, shorn animals may be more vulnerable to the cold, highly variable climatic conditions associated with these seasons. The objective of this study was to determine if late gestation shearing induces differences in individual BW, dry matter intake (DMI) and plasma metabolite concentration of finewool ewes managed outdoors during winter. Thirty-six mature, pregnant Rambouillet ewes (3.8±0.45 years; 76.8±11.4 kg) were managed in a drylot with ad libitum access to pelleted alfalfa in bunks capable of measuring individual daily DMI. The treatment group consisted of ewes sheared at ~5 weeks before the estimated parturition date (shorn; n=18). Unshorn ewes (n=18) remained in full fleece throughout the experiment and were shorn on the last day of the experiment ~2 weeks before the estimated parturition date. Blood was collected on days 0 (before shearing shorn group), 7, 14 and 21 (before shearing unshorn group) of the trial, and plasma was isolated and analyzed for non-esterified fatty acid (NEFA), β-hydroxybutyrate (BHB) and glucose (GLU) concentrations. There was no effect of shearing on ewe DMI or BW during the trial (P⩾0.35). Plasma NEFA and GLU concentrations were similar (P⩾0.36) between shearing groups, though plasma BHB concentration was 103.7 μmol/l greater (24.1%; P<0.01) in unshorn ewes. Lamb BW at birth was not affected (P=0.30) by ewe shearing treatment. Under conditions of this study, no differences in economically important aspects of sheep production were observed between shorn and unshorn pregnant ewes.
The aim of this paper is to examine Canadian key informants’ perceptions of intrapersonal (within an individual) and interpersonal (among individuals) factors that influence successful primary care and public health collaboration.
Primary health care systems can be strengthened by building stronger collaborations between primary care and public health. Although there is literature that explores interpersonal factors that can influence successful inter-organizational collaborations, a few of them have specifically explored primary care and public health collaboration. Furthermore, no papers were found that considered factors at the intrapersonal level. This paper aims to explore these gaps in a Canadian context.
This interpretative descriptive study involved key informants (service providers, managers, directors, and policy makers) who participated in one h telephone interviews to explore their perceptions of influences on successful primary care and public health collaboration. Transcripts were analyzed using NVivo 9.
A total of 74 participants [from the provinces of British Columbia (n=20); Ontario (n=19); Nova Scotia (n=21), and representatives from other provinces or national organizations (n=14)] participated. Five interpersonal factors were found that influenced public health and primary care collaborations including: (1) trusting and inclusive relationships; (2) shared values, beliefs and attitudes; (3) role clarity; (4) effective communication; and (5) decision processes. There were two influencing factors found at the intrapersonal level: (1) personal qualities, skills and knowledge; and (2) personal values, beliefs, and attitudes. A few differences were found across the three core provinces involved. There were several complex interactions identified among all inter and intra personal influencing factors: One key factor – effective communication – interacted with all of them. Results support and extend our understanding of what influences successful primary care and public health collaboration at these levels and are important considerations in building and sustaining primary care and public health collaborations.
The amount and nutrient content of small ruminant manure and its consequent value as a soil ameliorant will be largely determined by their diet (chemical composition of the plants consumed and their digestibility), and the efficiency of digestion, and will vary accordingly (Delve et al, 2001). This comparative study set out to evaluate the current and potential contribution of sheep and goats to soil fertility management in two villages located in different ecological zones in Ghana.
We concentrate on the application of centimeter wavelength observational data to the coronae of rapidly rotating active dwarf stars. In particular we seek insight into coronal loop geometries, and their possible relevance to the magnetic braking mechanism, which must play a key role in binary evolution scenarios for such stars.
Long-duration particle image velocimetry measurements in rough-bed open-channel flows (OCFs) reveal that the pre-multiplied spectra of the streamwise velocity have a bimodal distribution due to the presence of large- and very-large-scale motions (LSMs and VLSMs, respectively). The existence of VLSMs in boundary layers, pipes and closed channels has been acknowledged for some time, but strong supporting evidence for their presence in OCF has been lacking. The data reported in this paper fill this gap. Length scales of the LSMs and VLSMs in OCF exhibit different scaling properties; whereas the streamwise length of the LSM scales with the flow depth, the VLSM streamwise length does not scale purely with flow depth and may additionally depend on other scales such as the channel width, roughness height or viscous length. The transverse extent of the LSMs was found to increase with increasing elevation, but the VLSM transverse scale is anchored around two flow depths. The origin and nature of LSMs and VLSMs are still to be resolved, but differences in their scaling suggest that VLSMs in rough-bed OCFs form independently rather than as a spatial alignment of LSMs.
This study aimed to document the growth and challenges encountered in the decade since inception of the National Ambulance Service (NAS) in Ghana, West Africa. By doing so, potentially instructive examples for other low- and middle-income countries (LMICs) planning a formal prehospital care system or attempting to identify ways to improve existing emergency services could be identified.
Data routinely collected by the Ghana NAS from 2004-2014 were described, including: patient demographics, reason for the call, response location, target destination, and ti1mes of service. Additionally, the organizational structure and challenges encountered during the development and maturation of the NAS were reported.
In 2004, the NAS piloted operations with 69 newly trained emergency medical technicians (EMTs), nine ambulances, and seven stations. The NAS expanded service delivery with 199 ambulances at 128 stations operated by 1,651 EMTs and 47 administrative and maintenance staff in 2014. In 2004, nine percent of the country was covered by NAS services; in 2014, 81% of Ghana was covered. Health care transfers and roadside responses comprised the majority of services (43%-80% and 10%-57% by year, respectively). Increased mean response time, stable case holding time, and shorter vehicle engaged time reflect greater response ranges due to increased service uptake and improved efficiency of ambulance usage. Specific internal and external challenges with regard to NAS operations also were described.
The steady growth of the NAS is evidence of the need for Emergency Medical Services and the effects of sound planning and timely responses to changes in program indicators. The way forward includes further capacity building to increase the number of scene responses, strengthening ties with local health facilities to ensure timely emergency medical care and appropriateness of transfers, assuring a more stable funding stream, and improving public awareness of NAS services.
ZakariahA, StewartBT, BoatengE, AchenaC, TansleyG, MockC. The Birth and Growth of the National Ambulance Service in Ghana. Prehosp Disaster Med. 2017;32(1):83–93.
Shifting prey distributions due to global warming are expected to generate dramatic ecosystem-wide changes in trophic structure within Arctic marine ecosystems. Yet a relatively poor understanding of contemporary Arctic food webs makes it difficult to predict the consequences of such changes for Arctic predators. Doing so requires quantitative approaches that can track contemporary changes in predator diets through time, using accurate, well-defined methods. Here we use fatty acids (FA) to quantify differences in consumer diet using permutational multivariate analysis of variance tests that characterize spatial and temporal changes in consumer FA signatures. Specifically we explore differences in Greenland shark (Somniosus microcephalus) FA to differentiate their potential trophic role between Svalbard, Norway and Cumberland Sound, Canada. Greenland shark FA signatures revealed significant inter-annual differences, probably driven by varying seal and Greenland halibut responses to environmental conditions such as the NAO, bottom temperature, and annual sea-ice extent. Uncommon FA were also found to play an important role in driving spatial and temporal differences in Greenland shark FA profiles. Our statistical approach should facilitate quantification of changing consumer diets across a range of marine ecosystems.
Recent progress in graphite target production for sub-milligram environmental samples in our facility is presented. We describe an optimized hydrolysis procedure now routinely used for the preparation of CO2 from inorganic samples, a new high-vacuum line dedicated to small sample processing (combining sample distillation and graphitization units), as well as a modified graphitization procedure. Although measurements of graphite targets as small as 35 μg C have been achieved, system background and measurement uncertainties increase significantly below 150 μg C. As target lifetime can become critically short for targets <150 μg C, the facility currently only processes inorganic samples down to 150 μg C. All radiocarbon measurements are made at the Scottish Universities Environmental Research Centre (SUERC) accelerator mass spectrometry (AMS) facility. Sample processing and analysis are labor-intensive, taking approximately 3 times longer than samples ≥ 500 μg C. The technical details of the new system, graphitization yield, fractionation introduced during the process, and the system blank are discussed in detail.
Recent progress in preparation/combustion of submilligram organic samples at our laboratories is presented. Routine methods had to be modified/refined to achieve acceptable and consistent procedural blanks for organic samples smaller than 1000 μg C. A description of the process leading to a modified combustion method for smaller organic samples is given in detail. In addition to analyzing different background materials, the influence of different chemical reagents on the overall radiocarbon background level was investigated, such as carbon contamination arising from copper oxide of different purities and from different suppliers. Using the modified combustion method, small amounts of background materials and known-age standard IAEA-C5 were individually combusted to CO2. Below 1000 μg C, organic background levels follow an inverse mass dependency when combusted with the modified method, increasing from 0.13 ± 0.05 pMC up to 1.20 ± 0.04 pMC for 80 μg C. Results for a given carbon mass were lower for combustion of etched Iceland spar calcite mineral, indicating that part of the observed background of bituminous coal was probably introduced by handling the material in atmosphere prior to combustion. Using the modified combustion method, the background-corrected activity of IAEA-C5 agreed to within 2 σ of the consensus value of 23.05 pMC down to a sample mass of 55 μg C.
It is now almost 10 yr since radiocarbon dating of cremated bone was first developed using the small carbonate component contained within the hydroxyapatite-based inorganic fraction. Currently, a significant number of 14C laboratories date cremated bone as part of their routine dating service. As a general investigation of cremated bone dating since this initial development, a small, cremated bone intercomparison study took place in 2005, involving 6 laboratories. Six cremated bone samples (including 2 sets of duplicates), with ages spanning approximately 1500–2800 BP, were sent to the laboratories. The results, which showed relatively good agreement amongst the laboratories and between the duplicate samples, are discussed in detail.