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When a drop of fluid containing long, flexible polymers breaks up, it forms threads of almost constant thickness, whose size decreases exponentially in time. Using an Oldroyd-B fluid as a model, we show that the thread profile, rescaled by the thread thickness, converges to a similarity solution. Using the correspondence between viscoelastic fluids and nonlinear elasticity, we derive similarity equations for the full three-dimensional axisymmetric flow field in the limit that the viscosity of the solvent fluid can be neglected. Deriving a conservation law along the thread, we can calculate the stress inside the thread from a measurement of the thread thickness. The explicit form of the velocity and stress fields can be deduced from a solution of the similarity equations. Results are validated by detailed comparison with numerical simulations.
The Square Kilometre Array (SKA) is a planned large radio interferometer designed to operate over a wide range of frequencies, and with an order of magnitude greater sensitivity and survey speed than any current radio telescope. The SKA will address many important topics in astronomy, ranging from planet formation to distant galaxies. However, in this work, we consider the perspective of the SKA as a facility for studying physics. We review four areas in which the SKA is expected to make major contributions to our understanding of fundamental physics: cosmic dawn and reionisation; gravity and gravitational radiation; cosmology and dark energy; and dark matter and astroparticle physics. These discussions demonstrate that the SKA will be a spectacular physics machine, which will provide many new breakthroughs and novel insights on matter, energy, and spacetime.
Nutritional therapy is a cornerstone of burns management. The optimal macronutrient intake for wound healing after burn injury has not been identified, although high-energy, high-protein diets are favoured. This study aimed to identify the optimal macronutrient intake for burn wound healing. The Geometric Framework (GF) was used to analyse wound healing after a 10% TBSA contact burn in mice ad libitum fed one of 11 high-energy diets, varying in macronutrient composition with protein (P5%-60%), carbohydrate (C20%-75%) and fat (F20%-75%). In the GF study, the optimal ratio for wound healing was identified as a moderate-protein, high-carbohydrate diet with a protein:carbohydrate:fat (P:C:F) ratio of 1:4:2. High-carbohydrate intake was associated with lower mortality, improved body weight and a beneficial pattern of body fat reserves. Protein intake was essential to prevent weight loss and mortality, but a protein intake target of ~7 kJ/day (~15% of energy intake) was identified, above which no further benefit was gained. High-protein intake was associated with delayed wound healing and increased liver and spleen weight. As the GF study demonstrated that an initial very high-protein intake prevented mortality, a very high-protein, moderate-carbohydrate diet (P40:C42:F18) was specifically designed. The dynamic diet study was also designed to combine and validate the benefits of an initial very high-protein intake for mortality, and subsequent moderate-protein, high-carbohydrate intake for optimal wound healing. The dynamic feeding experiment showed switching from an initial very high-protein diet to the optimal moderate-protein, high-carbohydrate diet accelerated wound healing whilst preventing mortality and liver enlargement.
For their glucose supply, ruminants are highly dependent on the endogenous synthesis in the liver, but despite the numerous studies that evaluated hepatic glucose production, very few simultaneously measured hepatic glucose production and uptake of all precursors. As a result, the variability of precursor conversion into glucose in the liver is not known. The present study aimed at investigating by meta-analysis the relationships between hepatic glucose net release and uptake of precursors. We used the FLuxes of nutrients across Organs and tissues in Ruminant Animals database, which gathers international results on net nutrient fluxes at splanchnic level measured in catheterized animals. Response equations were developed for intakes up to 41 g DM intake/kg BW per day of diets varying from 0 to 100 g of concentrate/100 g DM in the absence of additives. The net hepatic uptake of propionate, α-amino-N and l-lactate was linearly and better related to their net portal appearance (NPA) than to their afferent hepatic flux. Blood flow data were corrected for lack of deacetylation of the para-aminohippuric acid, and this correction was shown to impact the response equations. To develop response equations between the availability of precursors (portal appearance and hepatic uptake) and net glucose hepatic release, missing data on precursor fluxes were predicted from dietary characteristics using previously developed response equations. Net hepatic release of glucose was curvilinearly related to hepatic supply and uptake of the sum of precursors, suggesting a lower conversion rate of precursors at high precursor supply. Factors of variation were explored for the linear portion of this relationship, which applied to NPA of precursors ranging from 0.99 to 9.60 mmol C/kg BW per h. Hepatic release of glucose was shown to be reduced by the portal absorption of glucose from diets containing bypass starch and to be increased by an increased uptake of β-hydroxybutyrate indicative of higher body tissue mobilization. These relationships were affected by the physiological status of the animals. In conclusion, we established equations that quantify the net release of glucose by the liver from the net availability of precursors. They provide a quantitative overview of factors regulating hepatic glucose synthesis in ruminants. These equations can be linked with the predictions of portal absorption of nutrients from intake and dietary characteristics, and provide indications of glucose synthesis from dietary characteristics.
Understanding the pattern of middle-ear cholesteatoma becomes pertinent with the rise of endoscopic surgery as surgeons decide on the optimal approach to visualise and extirpate disease. With modifications to the Telmesani attic–tympanum–mastoid staging system, this study aimed to evaluate the commonest patterns of middle-ear cholesteatoma and their implications for surgical approach.
A retrospective study was conducted in a single tertiary institution in Singapore. All patients undergoing cholesteatoma surgery between January 2012 and June 2015 were included. Staging of cholesteatoma was based on clinical assessment corroborated by radiological findings.
Out of the 55 ears included, 98.2 per cent had cholesteatoma involving the attic. The disease extended into the mastoid antrum and beyond in 43 cases (78.2 per cent). The facial recess and/or sinus tympanum was affected in 26 cases (47.3 per cent).
The majority of cholesteatoma cases present with extensive attic disease and significant mastoid involvement. In these cases, endoscopes may be best suited to adjunctive rather than exclusive use in surgery.
To assess potential transmission of antibiotic-resistant organisms (AROs) using surrogate markers and bacterial cultures.
A 1,260-bed tertiary-care academic medical center.
The study included 25 patients (17 of whom were on contact precautions for AROs) and 77 healthcare personnel (HCP).
Fluorescent powder (FP) and MS2 bacteriophage were applied in patient rooms. HCP visits to each room were observed for 2–4 hours; hand hygiene (HH) compliance was recorded. Surfaces inside and outside the room and HCP skin and clothing were assessed for fluorescence, and swabs were collected for MS2 detection by polymerase chain reaction (PCR) and selective bacterial cultures.
Transfer of FP was observed for 20 rooms (80%) and 26 HCP (34%). Transfer of MS2 was detected for 10 rooms (40%) and 15 HCP (19%). Bacterial cultures were positive for 1 room and 8 HCP (10%). Interactions with patients on contact precautions resulted in fewer FP detections than interactions with patients not on precautions (P < .001); MS2 detections did not differ by patient isolation status. Fluorescent powder detections did not differ by HCP type, but MS2 was recovered more frequently from physicians than from nurses (P = .03). Overall, HH compliance was better among HCP caring for patients on contact precautions than among HCP caring for patients not on precautions (P = .003), among nurses than among other nonphysician HCP at room entry (P = .002), and among nurses than among physicians at room exit (P = .03). Moreover, HCP who performed HH prior to assessment had fewer fluorescence detections (P = .008).
Contact precautions were associated with greater HCP HH compliance and reduced detection of FP and MS2.
Defining the risk factors for Eustachian tube dysfunction can facilitate its prevention. It is hypothesised that Eustachian tube dysfunction as measured by the Eustachian Tube Dysfunction Questionnaire-7 is associated with obstructive sleep apnoea syndrome.
The questionnaire was systematically translated into Hebrew and validated in the accepted manner. This questionnaire was applied to obstructive sleep apnoea syndrome patients before and after expansion sphincter pharyngoplasty, in pre-set time intervals. The results were compared to those of controls from the general population.
Thirty-one patients (males:females = 19:12) were enrolled in the obstructive sleep apnoea syndrome group. Mean age was 43 years (range, 31–55 years) and mean body mass index was 28 kg/m2 (range, 27–30 kg/m2). Median apnoea-hypopnea index (pre-operatively) was 34 events per hour. The questionnaire scores in expansion sphincter pharyngoplasty candidates were significantly worse than in controls (p < 0.001). Expansion sphincter pharyngoplasty did not change Eustachian tube function in the long term, but was associated with additional self-limiting Eustachian tube dysfunction in the first two post-operative months.
Eustachian tube dysfunction is significantly worse in patients with obstructive sleep apnoea syndrome compared to controls. Expansion sphincter pharyngoplasty is not associated with Eustachian tube function improvement.
Evidence suggests that early trauma may have a negative effect on cognitive functioning in individuals with psychosis, yet the relationship between childhood trauma and cognition among those at clinical high risk (CHR) for psychosis remains unexplored. Our sample consisted of 626 CHR children and 279 healthy controls who were recruited as part of the North American Prodrome Longitudinal Study 2. Childhood trauma up to the age of 16 (psychological, physical, and sexual abuse, emotional neglect, and bullying) was assessed by using the Childhood Trauma and Abuse Scale. Multiple domains of cognition were measured at baseline and at the time of psychosis conversion, using standardized assessments. In the CHR group, there was a trend for better performance in individuals who reported a history of multiple types of childhood trauma compared with those with no/one type of trauma (Cohen d = 0.16). A history of multiple trauma types was not associated with greater cognitive change in CHR converters over time. Our findings tentatively suggest there may be different mechanisms that lead to CHR states. Individuals who are at clinical high risk who have experienced multiple types of childhood trauma may have more typically developing premorbid cognitive functioning than those who reported minimal trauma do. Further research is needed to unravel the complexity of factors underlying the development of at-risk states.
Light Detection and Ranging (LiDAR) is a primary sensor for autonomous vehicles to recognize surroundings. It detects near-infrared (NIR) light pulses, typically at 905nm, which is emitted and reflected by surrounding objects. Here, the fact of the matter is that conventional black or dark-tone cars with extremely low NIR reflection are hard to be detected by LiDAR and endanger the future highway. In this work, we propose to use platelet-shaped effect pigments with visible absorption and NIR reflectivity. Copper(Ⅱ) oxide and Silicon dioxide multilayer are theoretically investigated with different numbers of layers and thicknesses. The optimized structures appear various dark-tone colors with high NIR-reflectivity over 90%.
Potential yield losses in grain sorghum due to weed interference based on quantitative data from the major grain sorghum growing areas of the United States of America are reported by the WSSA Weed Loss Committee. Weed scientists and extension specialists who researched weed control in grain sorghum provided data on grain sorghum yield loss due to weed interference in their region. Data were requested from up to 10 individual experiments per calendar year over 10 years between 2007 and 2016. Based on the summarized information, farmers in Arkansas, Kansas, Missouri, Nebraska, South Dakota, and Texas would potentially lose an average of 37, 38, 30, 56, 61, and 60% of their grain sorghum yield with no weed control, and have a corresponding annual monetary loss of US$ 19, 302, 7, 32, 25, and 314 million, respectively. The overall average yield loss due to weed interference was estimated to be 47% for this grain sorghum growing region. Thus, farmers in the USA would lose approximately 5.7 million tonnes of grain sorghum valued at approximately US$ 953 million annually if weeds are not controlled. With each dollar invested in weed management (based on estimated weed control cost of US$ 100 ha-1), there would be a return of US$ 3.80, highlighting the return on investment in weed management and the importance of continued weed science research for sustaining high grain sorghum yield and profitability in the USA.
Ocean warming and acidification are expected to influence the biology of the ecologically and economically important red king crab, Paralithodes camtschaticus. We investigated transcriptome responses of adult, larval and juvenile red king crab to assess sensitivity to reduced pH and elevated temperature. In adults, gill tissue (but not heart or cuticle) responded to reduced pH by differentially regulating many genes involved in metabolic, membrane and cuticular processes, but not ionic or acid/base regulation. In larval crabs, we found little evidence for a strong transcriptomic response to pH, but did observe large differences in the transcriptomes of newly hatched and one-week old larvae. In juvenile crabs, we found that there was a strong transcriptomic response to temperature across all pH conditions, but that only extreme low pH caused transcriptomic shifts. Most of the genes in juveniles that were differentially expressed were for cuticular and calcification processes. While inferences regarding the specific biological responses associated with changes in gene expression are likely to change as resources for red king crab genomics enabled studies continue to improve (i.e. better assemblies and annotation), our inferences about general sensitivities to temperature and pH across the life stages of red king crab are robust and unlikely to shift. Overall, our data suggest that red king crab are more sensitive to warming than acidification, and that responses to acidification at the transcriptomic level occur at different levels of pH across life stages, with juveniles being less pH sensitive than adults.
Studies suggest that alcohol consumption and alcohol use disorders have distinct genetic backgrounds.
We examined whether polygenic risk scores (PRS) for consumption and problem subscales of the Alcohol Use Disorders Identification Test (AUDIT-C, AUDIT-P) in the UK Biobank (UKB; N = 121 630) correlate with alcohol outcomes in four independent samples: an ascertained cohort, the Collaborative Study on the Genetics of Alcoholism (COGA; N = 6850), and population-based cohorts: Avon Longitudinal Study of Parents and Children (ALSPAC; N = 5911), Generation Scotland (GS; N = 17 461), and an independent subset of UKB (N = 245 947). Regression models and survival analyses tested whether the PRS were associated with the alcohol-related outcomes.
In COGA, AUDIT-P PRS was associated with alcohol dependence, AUD symptom count, maximum drinks (R2 = 0.47–0.68%, p = 2.0 × 10−8–1.0 × 10−10), and increased likelihood of onset of alcohol dependence (hazard ratio = 1.15, p = 4.7 × 10−8); AUDIT-C PRS was not an independent predictor of any phenotype. In ALSPAC, the AUDIT-C PRS was associated with alcohol dependence (R2 = 0.96%, p = 4.8 × 10−6). In GS, AUDIT-C PRS was a better predictor of weekly alcohol use (R2 = 0.27%, p = 5.5 × 10−11), while AUDIT-P PRS was more associated with problem drinking (R2 = 0.40%, p = 9.0 × 10−7). Lastly, AUDIT-P PRS was associated with ICD-based alcohol-related disorders in the UKB subset (R2 = 0.18%, p < 2.0 × 10−16).
AUDIT-P PRS was associated with a range of alcohol-related phenotypes across population-based and ascertained cohorts, while AUDIT-C PRS showed less utility in the ascertained cohort. We show that AUDIT-P is genetically correlated with both use and misuse and demonstrate the influence of ascertainment schemes on PRS analyses.
Quality improvement and patient safety (QIPS) competencies are increasingly important in emergency medicine (EM) and are now included in the CanMEDS framework. We conducted a survey aimed at determining the Canadian EM residents’ perspectives on the level of QIPS education and support available to them.
An electronic survey was distributed to all Canadian EM residents from the Royal College and Family Medicine training streams. The survey consisted of multiple-choice, Likert, and free-text entry questions aimed at understanding familiarity with QIPS, local opportunities for QIPS projects and mentorship, and the desire for further QIPS education and involvement.
Of 535 EM residents, 189 (35.3%) completed the survey, representing all 17 medical schools; 77.2% of respondents were from the Royal College stream; 17.5% of respondents reported that QIPS methodologies were formally taught in their residency program; 54.7% of respondents reported being “somewhat” or “very” familiar with QIPS; 47.2% and 51.5% of respondents reported either “not knowing” or “not having readily available” opportunities for QIPS projects and QIPS mentorship, respectively; 66.9% of respondents indicated a desire for increased QIPS teaching; and 70.4% were interested in becoming involved with QIPS training and initiatives.
Many Canadian EM residents perceive a lack of QIPS educational opportunities and support in their local setting. They are interested in receiving more QIPS education, as well as project and mentorship opportunities. Supporting residents with a robust QIPS educational and mentorship framework may build a cohort of providers who can enhance the local delivery of care.
An adaptive neural stress response is essential to adequately cope with a changing environment. It was previously argued that sympathetic/noradrenergic activity during acute stress increases salience network (SN) connectivity and reduces executive control network (ECN) connectivity in healthy controls, with opposing effects in the late aftermath of stress. Altered temporal dynamics of these networks in response to stress are thought to play a role in the development of psychopathology in vulnerable individuals.
We exposed male healthy controls (n = 40, mean age = 33.9) and unaffected siblings of schizophrenia patients (n = 39, mean age = 33.2) to the stress or control condition of the trier social stress test and subsequently investigated resting state functional connectivity of the SN and ECN directly after and 1.5 h after stress.
Acute stress resulted in increased functional connectivity within the SN in healthy controls, but not in siblings (group × stress interaction pfwe < 0.05). In the late aftermath of stress, stress reduced functional connectivity within the SN in both groups. Moreover, we found increased functional connectivity between the ECN and the cerebellum in the aftermath of stress in both healthy controls and siblings of schizophrenia patients.
The results show profound differences between siblings of schizophrenia patients and controls during acute stress. Siblings lacked the upregulation of neural resources necessary to quickly and adequately cope with a stressor. This points to a reduced dynamic range in the sympathetic response, and may constitute a vulnerability factor for the development of psychopathology in this at-risk group.
In the Netherlands, the bulk of the Miocene to lowest Pliocene sedimentary succession is currently assigned to a single lithostratigraphical unit, the Breda Formation. Although the formation was introduced over 40 years ago, the definition of its lower and upper boundaries is still problematic. Well-log correlations show that the improved lecto-stratotype for the Breda Formation in well Groote Heide partly overlaps with the additional reference section of the older Veldhoven Formation in the nearby well Broekhuizenvorst. The distinction between the Breda and the overlying Oosterhout Formation, which was mainly based on quantitative differences in glauconite and molluscs, gives rise to ongoing discussion, in particular due to the varying concentrations of glauconitic content that occur within both formations. In addition, the Breda Formation lacks a regional-scale stratigraphic framework which relates its various regionally to locally defined shallow marine to continental members.
In order to resolve these issues, we performed renewed analyses of material from several archived cores. The results of archived and new dinocyst analyses were combined with lithological descriptions and wire-line log correlations of multiple wells, including the wells Groote Heide and Broekhuizenvorst. In this process, the updated dinocyst zonation of Munsterman & Brinkhuis (2004), recalibrated to the Geological Time Scale of Ogg et al. (2016), was used. To establish regionally consistent lithostratigraphic boundaries, additional data was used along a transect across the Roer Valley Graben running from its central part (well St-Michielsgestel-1) towards the southern rift shoulders (well Goirle-1). Along this transect, chronostratigraphic and lithostratigraphic analyses were integrated with well-log correlation and the analyses of seismic reflection data to constrain geometrical/structural relationships as well.
The results led to the differentiation of two distinct seismic sequences distinguished by three recognisable unconformities: the Early Miocene Unconformity (EMU), the Mid-Miocene Unconformity (MMU) and the Late Miocene Unconformity (LMU). The major regional hiatus, referred to as the Mid-Miocene Unconformity, occurs intercalated within the present Breda Formation and compels subdivision of this unit into two formations, viz. the here newly established Groote Heide and the younger Diessen formations. Pending further studies, the former Breda Formation will be temporally raised in rank to the newly established Hilvarenbeek subgroup, which comprises both the Groote Heide and Diessen formations. Whereas these two sequences were already locally defined, a third sequence overlying the LMU represents two newly defined lithostratigraphical units, named the Goirle and the Tilburg members, positioned in this study at the base of the Oosterhout Formation. Besides their unique lithological characteristics, in seismic reflection profiles the Goirle and the Tilburg members stand out because of their distinct seismic facies.
Use of an integrated, multidisciplinary and regional approach, an improved southern North Sea framework and more comprehensive lithostratigraphic subdivision of Neogene successions is proposed for the Netherlands, to make (cross-border) correlations more straightforward in the future.
Glyphosate-resistant (GR) canola is a widely grown crop across western Canada and has quickly become a prolific volunteer weed. Glyphosate-resistant soybean is rapidly gaining acreage in western Canada. Thus, there is a need to evaluate herbicide options to manage volunteer GR canola in GR soybean crops. The present experiment was conducted to evaluate the efficacy of various PRE- and POST- emergence herbicides applied sequentially to volunteer GR canola, and to evaluate soybean injury caused by these herbicides. Trials were conducted across Saskatchewan and Manitoba in 2014 and 2015. All treatments provided a range of suppression (>70%) to control (>80%) of volunteer canola. All treatments with the exception of the glyphosate treated control reduced aboveground canola biomass by 96% (on average). As well, canola seed contamination was reduced from 36% to less than 5% when a PRE and POST herbicide were both used. Moreover, all combinations of herbicides used had excellent crop safety (<10%). All Pre and Post herbicide combinations provided better control of volunteer canola compared to the glyphosate only control, but tribenuron fb bentazon and tribenuron fb imazamox+bentazon provided solutions that were low cost, currently available (registered in western Canada) and had the potential to minimize development of herbicide resistance in other weeds.
In order to map quantitative trait loci (QTLs) for allometries of body compositions and metabolic traits in chicken, we phenotypically characterize the allometric growths of multiple body components and metabolic traits relative to BWs using joint allometric scaling models and then establish random regression models (RRMs) to fit genetic effects of markers and minor polygenes derived from the pedigree on the allometric scalings. Prior to statistically inferring the QTLs for the allometric scalings by solving the RRMs, the LASSO technique is adopted to rapidly shrink most of marker genetic effects to zero. Computer simulation analysis confirms the reliability and adaptability of the so-called LASSO-RRM mapping method. In the F2 population constructed by multiple families, we formulate two joint allometric scaling models of body compositions and metabolic traits, in which six of nine body compositions are tested as significant, while six of eight metabolic traits are as significant. For body compositions, a total of 14 QTLs, of which 9 dominant, were detected to be associated with the allometric scalings of drumstick, fat, heart, shank, liver and spleen to BWs; while for metabolic traits, a total of 19 QTLs also including 9 dominant be responsible for the allometries of T4, IGFI, IGFII, GLC, INS, IGR to BWs. The detectable QTLs or highly linked markers can be used to regulate relative growths of the body components and metabolic traits to BWs in marker-assisted breeding of chickens.
Temperate pasture species constitute a source of protein for dairy cattle. On the other hand, from an environmental perspective, their high N content can increase N excretion and nitrogenous gas emissions by livestock. This work explores the effect of energy supplementation on N use efficiency (NUE) and nitrogenous gas emissions from the excreta of dairy cows grazing a pasture of oat and ryegrass. The study was divided into two experiments: an evaluation of NUE in grazing dairy cows, and an evaluation of N-NH3 and N-N2O volatilizations from dairy cow excreta. In the first experiment, 12 lactating Holstein × Jersey F1 cows were allocated to a double 3 × 3 Latin square (three experimental periods of 17 days each) and subjected to three treatments: cows without supplementation (WS), cows supplemented at 4.2 kg DM of corn silage (CS) per day, and cows supplemented at 3.6 kg DM of ground corn (GC) per day. In the second experiment, samples of excreta were collected from the cows distributed among the treatments. Aliquots of dung and urine of each treatment plus one blank (control – no excreta) were allotted to a randomized block design to evaluate N-NH3 and N-N2O volatilization. Measurements were performed until day 25 for N-NH3 and until day 94 for N-N2O. Dietary N content in the supplemented cows was reduced by 20% (P < 0.001) compared with WS cows, regardless of the supplement. Corn silage cows had lower N intake (P < 0.001) than WS and GC cows (366 v. 426 g/day, respectively). Ground corn supplementation allowed cows to partition more N towards milk protein compared with the average milk protein of WS cows or those supplemented with corn silage (117 v. 108 g/day, respectively; P < 0.01). Thus, even though they were in different forms, both supplements were able to increase (P < 0.01) NUE from 27% in WS cows to 32% in supplemented cows. Supplementation was also effective in reducing N excretion (761 v. 694 g/kg of Nintake; P < 0.001), N-NH3 emission (478 v. 374 g/kg of Nmilk; P < 0.01) and N-N2O emission (11 v. 8 g/kg of Nmilk; P < 0.001). Corn silage and ground corn can be strategically used as feed supplements to improve NUE, and they have the potential to mitigate N-NH3 and N-N2O emissions from the excreta of dairy cows grazing high-protein pastures.