Symmetry-breaking-induced internal mixing enhancement of droplet collision

Binary droplet collision is a basic fluid phenomenon for many spray processes in nature and industry involving lots of discrete droplets. It exists an inherent mirror symmetry between two colliding droplets. For specific cases of the collision between two identical droplets, the head-on collision and the off-center collision, respectively, show the axisymmetric and rotational symmetry characteristics, which is useful for the simplification of droplet collision modeling. However, for more general cases of the collision between two droplets involving the disparities of size ratio, surface tension, viscosity, and self-spin motions, the axisymmetric and rotational symmetry droplet deformation and inner flow tend to be broken, leading to many distinct phenomena that cannot occur for the collision between two identical droplets owing to the mirror symmetry. This review focused on interpreting the asymmetric droplet deformation and the collision-induced internal mixing that was affected by those symmetry breaking factors, such as size ratio effects, Marangoni Effects, non-Newtonian effects, and droplet self-spin motion. It helps to understand the droplet internal mixing for hypergolic propellants in the rocket engineering and microscale droplet reactors in the biological engineering, and the modeling of droplet collision in real combustion spray processes

In-flame soot quantification of diesel sprays under sooting/non-sooting critical conditions in an optical engine

[EN] Because of the challenge of meeting stringent emissions regulations for internal combustion engines, some advanced low temperature combustion modes have been raised in recent decades to improve combustion efficiency. Therefore, detailed understanding and capability for accurate prediction of in-flame soot processes under such low sooting conditions are becoming necessary. Nowadays, a lot of investigations have been carried out to quantify in-flame soot in Diesel sprays under high sooting conditions by means of different optical techniques. However, no information of soot quantification can be found for sooting/non-sooting critical conditions. In current study, the instantaneous soot production in a two-stroke optical engine under low sooting conditions has been measured by means of a Diffused back-illumination extinction technique (DBI) and two-color method (2C) simultaneously. The fuels used were n-dodecane and n-heptane, which have been injected separately though two different injectors equipped with single-hole nozzles. A large cycle-to-cycle variation on soot production can be observed under such operating conditions, however the in-cylinder heat release traces were quite repeatable. It is the same with the well-known trends of soot amount to operating conditions that the probability of sooting cycles increases with higher ambient temperature, higher ambient density and lower injection pressure. Both techniques present a pretty good agreement on soot amount when the peak of KL value is close to 1. However, the KL value of two-color method becomes bigger than that of DBI and the difference increases with lower sooting conditions.This study was partially funded by the Natural Science Foundation of China (No. 51876083), China Postdoctoral Science Foundation (2018M642176) and High-tech Research Key laboratory of Zhenjiang (SS2018002)Xuan, T.; Pastor, JV.; García-Oliver, JM.; García Martínez, A.; He, Z.; Wang, Q.; Reyes, M. (2019). In-flame soot quantification of diesel sprays under sooting/non-sooting critical conditions in an optical engine. Applied Thermal Engineering. 149:1-10. https://doi.org/10.1016/j.applthermaleng.2018.11.112S11014

Septin 9 isoform expression, localization and epigenetic changes during human and mouse breast cancer progression

International audienceABSTRACT: INTRODUCTION: Altered expression of Septin 9 (SEPT9), a septin coding for multiple isoform variants, has been observed in several carcinomas including colorectal, head and neck, ovarian and breast, compared to normal tissue. Mechanisms regulating its expression during tumor initiation and progression in vivo and the oncogenic function of its different isoforms remain elusive. METHODS: Using an integrative approach, we investigated SEPT9 at the genetic, epigenetic, mRNA, and protein levels in breast cancer. We analyzed a panel of breast cancer cell lines, human primary tumors and corresponding tumor-free areas, normal breast from reduction mammoplasty patients, as well as primary mammary gland adenocarcinomas derived from the Polyoma Virus Middle T antigen mouse model (PyMT). MCF7 clones expressing individual GFP-tagged SEPT9 isoforms were used to determine their respective intracellular distribution and affect on cell migration. RESULTS: An overall increase in gene amplification and altered expression of SEPT9 was observed during breast tumorigenesis. We identified an intragenic alternative promoter whose methylation regulates SEPT9_v3 expression. Transfection of specific GFP-SEPT9 isoforms in MCF7 cells indicates that these isoforms exhibit differential localization and affect migration rates. Additionally, the loss of an uncharacterized SEPT9 nucleolar localization is observed during tumorigenesis. CONCLUSIONS: In this study we found conserved in vivo changes of SEPT9 gene amplification and overexpression during human and mouse breast tumorigenesis. We show that DNA methylation is a prominent mechanism responsible for regulating differential SEPT9 isoform expression and that breast tumor samples exhibit distinctive SEPT9 intracellular localization. Together, these findings support the significance of SEPT9 as a promising tool in breast cancer detection and further emphasize the importance of analyzing and targeting SEPT9 isoform specific expression and function

A reference-grade wild soybean genome

Wild relatives of crop plants are invaluable germplasm for genetic improvement. Here, Xie et al. report a reference-grade wild soybean genome and show that it can be used to identify structural variation and refine quantitative trait loci

A reference-grade wild soybean genome

Efficient crop improvement depends on the application of accurate genetic information contained in diverse germplasm resources. Here we report a reference-grade genome of wild soybean accession W05, with a final assembled genome size of 1013.2 Mb and a contig N50 of 3.3 Mb. The analytical power of the W05 genome is demonstrated by several examples. First, we identify an inversion at the locus determining seed coat color during domestication. Second, a translocation event between chromosomes 11 and 13 of some genotypes is shown to interfere with the assignment of QTLs. Third, we find a region containing copy number variations of the Kunitz trypsin inhibitor (KTI) genes. Such findings illustrate the power of this assembly in the analysis of large structural variations in soybean germplasm collections. The wild soybean genome assembly has wide applications in comparative genomic and evolutionary studies, as well as in crop breeding and improvement programs

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Grey Prediction Analysis on the Scale of Cross-Border E-Commerce Retail Import Transaction in Hainan

Combined with the policy of Hainan free trade port, the advantages of cross-border e-commerce enable the retail import cross-border e-commerce of Hainan free trade port develop rapidly, but Hainan cross-border e-commerce started late, and the data is very limited, so there is almost no reference econometric model. Therefore, this paper used the grey prediction GM (1,1) model to make a short-term prediction analysis of Hainan cross-border e-commerce retail import transaction scale, and used the residual correction model to improve the prediction accuracy, hoping to provide data reference and relevant policy basis for subsequent researchers and managers by analyzing the results in many aspects

Effect of nozzle hole size coupling with exhaust gas re-circulation on the engine emission perfomance based on KH-ACT spray model

To research an effective measure of reducing the Soot and NOx in engine at the same time, different nozzle hole diameters coupled with exhaust gas recirculation (EGR) were adopted in this study based on KH-ACT spray breakup model, which takes the aerodynamic-induced ,cavitation-induced and turbulence-induced breakup into account. The SAGE detailed chemistry combustion and the new atomization model used in the simulation have been verified with the experiment data from a YN4100QBZL engine. Different diesel nozzles was adopted in the study combined with different EGR rates ranging from 0% to 40%. The simulation results show that the NOx emission could be reduced effectively for both small(0.1mm) and large(0.15mm) diesel nozzle when increasing EGR ratio. The soot emission increases for the small nozzle hole size as the EGR increasing. However, when it comes to the large diesel nozzle, the emission increases slightly first and decrease quickly when the EGR rate above 20%