21 research outputs found
Impacting of droplets on moving surface and inclined surfaces
Drop impact onto inclined and moving surfaces are seen in various applications, for example, inkjet printing, spray coating, or in agriculture; droplets impact on either the surface that is moving, inclined, or a combination of both. Studies in the literature have examined the phenomenon of drop impact in isolation, either for a moving surface, or an inclined surface. Therefore, we conducted a comparative study for drop impact onto moving and inclined surfaces to see if they can be considered as equivalent systems. We used high speed imaging and examined the spreading and splashing of droplet impact onto both inclined and moving surfaces, having the same normal and tangential (in-plane) velocities. Various liquids with viscosities and surface tensions in the range of 1-5 cSt 17.4-72.8 mNm, respectively, were used. We demonstrated that both systems are equivalent to one another, considering either the initial spreading behavior of droplets, or splashing. Different types of splashing seen on inclined and moving surfaces are similar regardless of system. Finally, a new type of splashing named "split splashing"was also reported. This type of splashing is seen only when the normal velocity relative to tangential velocity is very low
First report of larval forms of Paragnathia sp. (Crustacea: Isopoda: Gnathidae) from Pakistani waters (Makri Creek)
The present report is based on the study of sample collected from Ghora
Bari (Makri Creek) on May 29, 2006 for the purpose of non-penaeid shrimps
exploitation. The sample, besides having shrimps have fishes belonging to several species
and isopod parasites in large numbers. The environmental parameters recorded are: water
temperature 31oC, Salinity 42 ppt and pH 8.7. Two larval stages of Paragnathia sp. are
described, illustrated and compared with the available descriptions of Paragnathia
formica pranizae larvae given earlier. The specimens are placed only tentatively in
Paragnathia sp. till the authors find adult specimens nevertheless this is the first report of
the genus and the larvae from the area
Probiotics, prematurity and neurodevelopment: Follow-up of a randomised trial
Objective: To determine the impact of one probiotics combination on the neurodevelopment of very preterm children at 2–5 years corrected gestational age (CA). Design: Follow-up study of survivors of a double-blinded, placebo-controlled, randomised trial of probiotic effects on late-onset sepsis in very preterm infants that found reduced necrotising enterocolitis. Setting: 10 tertiary perinatal centres in Australia and New Zealand. Patients: 1099 very preterm infants born <32 weeks’ gestation and weighing <1500 g. Intervention: Probiotics (Bifidobacterium infantis, Streptococcus thermophilus and Bifidobacterium lactis) or placebo administered from birth until discharge home or term CA, whichever came sooner. Main outcome measures: Major neurodevelopmental impairment comprised any of moderate/severe cerebral palsy (Gross Motor Function Classification System score 2–5), motor impairment (Bayley-III Motor Composite Scale <–2SD or Movement Assessment Battery for Children <15th centile if ≫42 months’ CA), cognitive impairment (Bayley-III Composite Cognitive or Language Scales <–2SD or Wechsler Preschool and Primary Scale of Intelligence Full Scale Intelligence Quotient <–2SD if ≫42 months’ CA), blindness or deafness. Results: Outcome data were available for 735 (67%) participants, with 71 deaths and 664/1028 survivors assessed at a mean age of 30 months. Survival free of major neurodevelopmental impairment was comparable between groups (probiotics 281 (75.3%) vs placebo 271 (74.9%); relative risk 1.01 (95% CI 0.93 to 1.09)). Rates of deafness were lower in probiotic-treated children (0.6% vs 3.4%). Conclusion: Administration of the probiotics combination Bifidobacterium infantis, Streptococcus thermophilus and Bifidobacterium lactis to very preterm babies from soon after birth until discharge home or term CA did not adversely affect neurodevelopment or behaviour in early childhood
Two-Year Outcomes After Minimally Invasive Surfactant Therapy in Preterm Infants: Follow-Up of the OPTIMIST-A Randomized Clinical Trial
Importance: The long-term effects of surfactant administration via a thin catheter (minimally invasive surfactant therapy [MIST]) in preterm infants with respiratory distress syndrome remain to be definitively clarified. /
Objective: To examine the effect of MIST on death or neurodevelopmental disability (NDD) at 2 years' corrected age.
/ Design, Setting, and Participants: Follow-up study of a randomized clinical trial with blinding of clinicians and outcome assessors conducted in 33 tertiary-level neonatal intensive care units in 11 countries. The trial included 486 infants with a gestational age of 25 to 28 weeks supported with continuous positive airway pressure (CPAP). Collection of follow-up data at 2 years' corrected age was completed on December 9, 2022.
/ Interventions: Infants assigned to MIST (n = 242) received exogenous surfactant (200 mg/kg poractant alfa) via a thin catheter; those assigned to the control group (n = 244) received sham treatment.
/ Main Outcomes and Measures: The key secondary outcome of death or moderate to severe NDD was assessed at 2 years' corrected age. Other secondary outcomes included components of this composite outcome, as well as hospitalizations for respiratory illness and parent-reported wheezing or breathing difficulty in the first 2 years.
/ Results: Among the 486 infants randomized, 453 had follow-up data available (median gestation, 27.3 weeks; 228 females [50.3%]); data on the key secondary outcome were available in 434 infants. Death or NDD occurred in 78 infants (36.3%) in the MIST group and 79 (36.1%) in the control group (risk difference, 0% [95% CI, -7.6% to 7.7%]; relative risk [RR], 1.0 [95% CI, 0.81-1.24]); components of this outcome did not differ significantly between groups. Secondary respiratory outcomes favored the MIST group. Hospitalization with respiratory illness occurred in 49 infants (25.1%) in the MIST group vs 78 (38.2%) in the control group (RR, 0.66 [95% CI, 0.54-0.81]) and parent-reported wheezing or breathing difficulty in 73 (40.6%) vs 104 (53.6%), respectively (RR, 0.76 [95% CI, 0.63-0.90]).
/ Conclusions and Relevance: In this follow-up study of a randomized clinical trial of preterm infants with respiratory distress syndrome supported with CPAP, MIST compared with sham treatment did not reduce the incidence of death or NDD by 2 years of age. However, infants who received MIST had lower rates of adverse respiratory outcomes during their first 2 years of life.
/ Trial Registration: anzctr.org.au Identifier: ACTRN12611000916943
Trends in Outcomes for Neonates Born Very Preterm and Very Low Birth Weight in 11 High-Income Countries
Objective
To evaluate outcome trends of neonates born very preterm in 11 high-income countries participating in the International Network for Evaluating Outcomes of neonates. Study design In a retrospective cohort study, we included 154 233 neonates admitted to 529 neonatal units between January 1, 2007, and December 31, 2015, at 24(0/7) to 31(6/7) weeks of gestational age and birth weight <1500 g. Composite outcomes were in-hospital mortality or any of severe neurologic injury, treated retinopathy of prematurity, and bronchopulmonary dysplasia (BPD); and same composite outcome excluding BPD. Secondary outcomes were mortality and individual morbidities. For each country, annual outcome trends and adjusted relative risks comparing epoch 2 (2012-2015) to epoch 1 (2007-2011) were analyzed.
Results
For composite outcome including BPD, the trend decreased in Canada and Israel but increased in Australia and New Zealand, Japan, Spain, Sweden, and the United Kingdom. For composite outcome excluding BPD, the trend decreased in all countries except Spain, Sweden, Tuscany, and the United Kingdom. The risk of composite outcome was lower in epoch 2 than epoch 1 in Canada (adjusted relative risks 0.78; 95% CI 0.74-0.82) only. The risk of composite outcome excluding BPD was significantly lower in epoch 2 compared with epoch 1 in Australia and New Zealand, Canada, Finland, Japan, and Switzerland. Mortality rates reduced in most countries in epoch 2. BPD rates increased significantly in all countries except Canada, Israel, Finland, and Tuscany.
Conclusions
In most countries, mortality decreased whereas BPD increased for neonates born very preterm
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PANC Study (Pancreatitis: A National Cohort Study): national cohort study examining the first 30 days from presentation of acute pancreatitis in the UK
Background
Acute pancreatitis is a common, yet complex, emergency surgical presentation. Multiple guidelines exist and management can vary significantly. The aim of this first UK, multicentre, prospective cohort study was to assess the variation in management of acute pancreatitis to guide resource planning and optimize treatment.
Methods
All patients aged greater than or equal to 18 years presenting with acute pancreatitis, as per the Atlanta criteria, from March to April 2021 were eligible for inclusion and followed up for 30 days. Anonymized data were uploaded to a secure electronic database in line with local governance approvals.
Results
A total of 113 hospitals contributed data on 2580 patients, with an equal sex distribution and a mean age of 57 years. The aetiology was gallstones in 50.6 per cent, with idiopathic the next most common (22.4 per cent). In addition to the 7.6 per cent with a diagnosis of chronic pancreatitis, 20.1 per cent of patients had a previous episode of acute pancreatitis. One in 20 patients were classed as having severe pancreatitis, as per the Atlanta criteria. The overall mortality rate was 2.3 per cent at 30 days, but rose to one in three in the severe group. Predictors of death included male sex, increased age, and frailty; previous acute pancreatitis and gallstones as aetiologies were protective. Smoking status and body mass index did not affect death.
Conclusion
Most patients presenting with acute pancreatitis have a mild, self-limiting disease. Rates of patients with idiopathic pancreatitis are high. Recurrent attacks of pancreatitis are common, but are likely to have reduced risk of death on subsequent admissions
Spreading of low-viscous liquids on a stationary and a moving surface
Abstract: This paper examines the time evolution for spreading of low surface tension liquids upon impact onto a surface, and highlights the differences with the same, for high surface tension liquids. Furthermore, it examines the role of the in-plane velocity (V P ) on the time evolution of spreading phase of the impact phenomena; V P is seen when the surface is inclined, or when the surface is moving in the horizontal direction, for impact of a free-falling droplet. High-speed imaging was used to capture the spreading phenomenon from side and overhead views. It was observed that low and high surface tension liquids spread in a different manner on both stationary and moving surfaces with different outcomes regarding the time to the maximum spreading diameter, and the maximum spreading factor. Also, compared to high surface tension liquids, the stretching of lamella in the direction of the in-plane velocity vector, is more pronounced for low surface tension liquids. We observed that on a moving surface, the position of the maximum width shifts more to the center of the lamella for low surface tension liquids, compared to that of high surface tension liquids, and this shifting increases with an increase in in-plane velocity. We developed a method and related equations to describe the time evolution of the lamella as drop spreads on a hydrophilic surface. Using our method, one can predict the spreading of both low and high surface tension liquids over stationary and moving surfaces (i.e., when in-plane velocity exists). Graphical abstract: [Figure not available: see fulltext.] Top view of droplets impacting a moving surface: Same Impact Conditions, but different shapes for spreading, and time to max spreading seen, and explained