Experimental understanding on the dynamics of micro-explosion and puffing in ternary emulsion droplets

Dynamics of puffing and micro-explosion phenomena occurring in ternary fuel emulsion droplets under high temperature environment were explored using high speed backlight imaging technique. A single droplet composed of diesel-biodiesel-ethanol emulsion was placed at the tip of a 75 µm gauge thermocouple and introduced rapidly into a furnace maintained at 500 °C. Several interesting features such as oscillation of suspended droplets, physical transformations occurring within the droplet, vapour expulsion, puffing, micro-explosion, sheet formation, perforations, growth of perforations, sheet disintegration and rotation of secondary droplets were observed. High resolution image analysis revealed separation of emulsion components within the core of the suspended droplet, which appeared either as a single nucleus or multiple nuclei. Two distinct types of micro-explosion were identified. For droplets encountering a single nucleus at the core resulted in a stronger vapour expulsion followed by intense micro-explosion. For droplets having multiple nuclei at the core resulted in a weaker vapour expulsion and slower growth of droplet prior to micro-explosion. Both types of micro-explosion process resulted in a number of child droplets. For the case of strong vapour expulsion nearly 80% of its child droplets have their sizes distributed within 150 μm compared to 60% for weaker vapour expulsion. The child droplets that were generated from the primary events of both puffing and micro-explosion cascaded further into secondary and tertiary events of puffing and micro-explosion in freely suspended environment.EPSR

Evidence for a fractional quantum Hall state with anisotropic longitudinal transport

At high magnetic fields, where the Fermi level lies in the N=0 lowest Landau level (LL), a clean two-dimensional electron system (2DES) exhibits numerous incompressible liquid phases which display the fractional quantized Hall effect (FQHE) (Das Sarma and Pinczuk, 1997). These liquid phases do not break rotational symmetry, exhibiting resistivities which are isotropic in the plane. In contrast, at lower fields, when the Fermi level lies in the $N\ge2$ third and several higher LLs, the 2DES displays a distinctly different class of collective states. In particular, near half filling of these high LLs the 2DES exhibits a strongly anisotropic longitudinal resistance at low temperatures (Lilly et al., 1999; Du et al., 1999). These "stripe" phases, which do not exhibit the quantized Hall effect, resemble nematic liquid crystals, possessing broken rotational symmetry and orientational order (Koulakov et al., 1996; Fogler et al., 1996; Moessner and Chalker, 1996; Fradkin and Kivelson, 1999; Fradkin et al, 2010). Here we report a surprising new observation: An electronic configuration in the N=1 second LL whose resistivity tensor simultaneously displays a robust fractionally quantized Hall plateau and a strongly anisotropic longitudinal resistance resembling that of the stripe phases.Comment: Nature Physics, (2011

Base-Pairing Versatility Determines Wobble Sites in tRNA Anticodons of Vertebrate Mitogenomes

BACKGROUND: Vertebrate mitochondrial genomes typically have one transfer RNA (tRNA) for each synonymous codon family. This limited anticodon repertoire implies that each tRNA anticodon needs to wobble (establish a non-Watson-Crick base pairing between two nucleotides in RNA molecules) to recognize one or more synonymous codons. Different hypotheses have been proposed to explain the factors that determine the nucleotide composition of wobble sites in vertebrate mitochondrial tRNA anticodons. Until now, the two major postulates--the "codon-anticodon adaptation hypothesis" and the "wobble versatility hypothesis"--have not been formally tested in vertebrate mitochondria because both make the same predictions regarding the composition of anticodon wobble sites. The same is true for the more recent "wobble cost hypothesis". PRINCIPAL FINDINGS: In this study we have analyzed the occurrence of synonymous codons and tRNA anticodon wobble sites in 1553 complete vertebrate mitochondrial genomes, focusing on three fish species with mtDNA codon usage bias reversal (L-strand is GT-rich). These mitogenomes constitute an excellent opportunity to study the evolution of the wobble nucleotide composition of tRNA anticodons because due to the reversal the predictions for the anticodon wobble sites differ between the existing hypotheses. We observed that none of the wobble sites of tRNA anticodons in these unusual mitochondrial genomes coevolved to match the new overall codon usage bias, suggesting that nucleotides at the wobble sites of tRNA anticodons in vertebrate mitochondrial genomes are determined by wobble versatility. CONCLUSIONS/SIGNIFICANCE: Our results suggest that, at wobble sites of tRNA anticodons in vertebrate mitogenomes, selection favors the most versatile nucleotide in terms of wobble base-pairing stability and that wobble site composition is not influenced by codon usage. These results are in agreement with the "wobble versatility hypothesis"

DALC: Distributed Automatic LSTM Customization for Fine-Grained Traffic Speed Prediction

Over the past decade, several approaches have been introduced for short-term traffic prediction. However, providing fine-grained traffic prediction for large-scale transportation networks where numerous detectors are geographically deployed to collect traffic data is still an open issue. To address this issue, in this paper, we formulate the problem of customizing an LSTM model for a single detector into a finite Markov decision process and then introduce an Automatic LSTM Customization (ALC) algorithm to automatically customize an LSTM model for a single detector such that the corresponding prediction accuracy can be as satisfactory as possible and the time consumption can be as low as possible. Based on the ALC algorithm, we introduce a distributed approach called Distributed Automatic LSTM Customization (DALC) to customize an LSTM model for every detector in large-scale transportation networks. Our experiment demonstrates that the DALC provides higher prediction accuracy than several approaches provided by Apache Spark MLlib.Comment: 12 pages, 5 figures, the 34th International Conference on Advanced Information Networking and Applications (AINA 2020), Springe

Chronic Arsenic Exposure and Cardiac Repolarization Abnormalities with QT Interval Prolongation in a Population-based Study

BACKGROUND: Chronic arsenic exposure is associated with cardiovascular abnormalities. Prolongation of the QT (time between initial deflection of QRS complex to the end of T wave) interval and profound repolarization changes on electrocardiogram (ECG) have been reported in patients with acute promyelocytic leukemia treated with arsenic trioxide. This acquired form of long QT syndrome can result in life-threatening arrhythmias. OBJECTIVE: The objective of this study was to assess the cardiac effects of arsenic by investigating QT interval alterations in a human population chronically exposed to arsenic. METHODS: Residents in Ba Men, Inner Mongolia, have been chronically exposed to arsenic via consumption of water from artesian wells. A total of 313 Ba Men residents with the mean arsenic exposure of 15 years were divided into three arsenic exposure groups: low (≤ 21 μg/L), medium (100–300 μg/L), and high (430–690 μg/L). ECGs were obtained on all study subjects. The normal range for QTc (corrected QT) interval is 0.33–0.44 sec, and QTc ≥ 0.45 sec was considered to be prolonged. RESULTS: The prevalence rates of QT prolongation and water arsenic concentrations showed a dose-dependent relationship (p = 0.001). The prevalence rates of QTc prolongation were 3.9, 11.1, 20.6% for low, medium, and high arsenic exposure, respectively. QTc prolongation was also associated with sex (p < 0.0001) but not age (p = 0.486) or smoking (p = 0.1018). Females were more susceptible to QT prolongation than males. CONCLUSIONS: We found significant association between chronic arsenic exposure and QT interval prolongation in a human population. QT interval may potentially be useful in the detection of early cardiac arsenic toxicity

The anti-inflammatory effects of dimethyl fumarate in astrocytes involve glutathione and haem oxygenase-1

DMF (dimethyl fumarate) exerts anti-inflammatory and pro-metabolic effects in a variety of cell types, and a formulation (BG-12) is being evaluated for monotherapy in multiple sclerosis patients. DMF modifies glutathione (GSH) levels that can induce expression of the anti-inflammatory protein HO-1 (haem oxygenase-1). In primary astrocytes and C6 glioma cells, BG-12 dose-dependently suppressed nitrite production induced by either LI [LPS (lipopolysaccharide) at 1 \u3bcg/ml plus IFN\u3b3 (interferon \u3b3) at 20 units/ml] or a mixture of pro-inflammatory cytokines, with greater efficacy in C6 cells. BG-12 reduced NOS2 (nitric oxide synthase 2) mRNA levels and activation of a NOS2 promoter, reduced nuclear levels of NF-\u3baB (nuclear factor \u3baB) p65 subunit and attenuated loss of I\u3baB\u3b1 (inhibitory \u3baB\u3b1) in both cell types, although with greater effects in astrocytes. In astrocytes, LI decreased mRNA levels for GSHr (GSH reductase) and GCL (c-glutamylcysteine synthetase), and slightly suppressed GSHs (GSH synthetase) mRNAs. Co-treatment with BG-12 prevented those decreased and increased levels above control values. In contrast, LI reduced GSHp (GSH peroxidase) and GCL in C6 cells, and BG-12 had no effect on those levels. BG-12 increased nuclear levels of Nrf2 (nuclear factor-erythroid 2 p45 subunit-related factor 2), an inducer of GSH-related enzymes, in astrocytes but not C6 cells. In astrocytes, GSH was decreased by BG-12 at 2 h and increased at 24 h. Prior depletion of GSH using buthionine-sulfoximine increased the ability of BG-12 to reduce nitrites. In astrocytes, BG-12 increased HO-1 mRNA levels and effects on nitrite levels were blocked by an HO-1 inhibitor. These results demonstrate that BG-12 suppresses inflammatory activation in astrocytes and C6 glioma cells, but with distinct mechanisms, different dependence on GSH and different effects on transcription factor activation

Prenatal muscle development in a mouse model for the secondary dystroglycanopathies

The defective glycosylation of α-dystroglycan is associated with a group of muscular dystrophies that are collectively referred to as the secondary dystroglycanopathies. Mutations in the gene encoding fukutin-related protein (FKRP) are one of the most common causes of secondary dystroglycanopathy in the UK and are associated with a wide spectrum of disease. Whilst central nervous system involvement has a prenatal onset, no studies have addressed prenatal muscle development in any of the mouse models for this group of diseases. In view of the pivotal role of α-dystroglycan in early basement membrane formation, we sought to determine if the muscle formation was altered in a mouse model of FKRP-related dystrophy

Enhanced catalytic activity of H2 heat-treated porous ceria for direct conversion of carbon dioxide into dimethyl carbonate

This is the final version. Available on open access from Elsevier via the DOI in this record. Data availability: No data was used for the research described in the article.It has been demonstrated that the specific surface area, acid–base properties, morphologies, and oxygen-vacancies (Ov) play a role in the catalytic performance of CeO2-based catalysts. In this study, porous CeO2 and Zr-doped CeO2 catalysts with high surface area have been prepared via a low temperature synthesis strategy and evaluated for the conversion of CO2 and methanol into dimethyl carbonate (DMC). Results show that the Zr doping (Zr:Ce = 1:9) could slightly increase the DMC formation rate of CeO2, whereas the H2 heat-treatment of CeO2 could lead to a DMC formation rate of 18.22 ± 0.64 mmol g–1h−1, which is amongst the highest for CeO2 catalysts at 140 °C reported so far. Such enhancement in DMC formation rate is attributed to (1) the balanced crystallinity and defects of the CeO2, (2) a shift of acid and base activity to lower temperature, and (3) the (1 1 1) plane only surface termination of the catalyst resulted from the heat-treatment process. Excluding the best performed H2 heat-treated CeO2 catalyst, the DMC formation rate of the rest catalysts shows a positive link to the BET surface area, acid property (NH3-TPD), OV%, Ce3+%, and the Raman peak intensity ratio of ID/IF2g of the catalyst. The low temperature preparation strategy in this study could be applicable to the synthesis of CeO2 catalyst towards other reactions (e.g., non-reductive CO2 conversions to various carbonates, carbamates, urea derivatives, etc.).Royal SocietyLeverhulme TrustNational Science and Technology Council (NSTC), Taiwa

Transmembrane protease serine 5: a novel Schwann cell plasma marker for CMT1A

OBJECTIVE: Development of biomarkers for Charcot-Marie-Tooth (CMT) disease is critical for implementing effective clinical trials. The most common form of CMT, type 1A, is caused by a genomic duplication surrounding the PMP22 gene. A recent report (Neurology 2018;90:e518-3524) showed elevation of neurofilament light (NfL) in plasma of CMT1A disease patients, which correlated with disease severity. However, no plasma/serum biomarker has been identified that is specific to Schwann cells, the most directly affected cells in CMT1A. METHODS: We used the Olink immuno PCR platform to profile CMT1A patient (n = 47, 2 cohorts) and normal control plasma (n = 41, two cohorts) on five different Olink panels to screen 398 unique proteins. RESULTS: The TMPRSS5 protein (Transmembrane protease serine 5) was elevated 2.07-fold (P = <0.0001) in two independent cohorts of CMT1A samples relative to controls. TMPRSS5 is most highly expressed in Schwann cells of peripheral nerve. Consistent with early myelination deficits in CMT1A, TMPRSS5 was not significantly correlated with disease score (CMTES-R, CMTNS-R), nerve conduction velocities (Ulnar CMAP, Ulnar MNCV), or with age. TMPRSS5 was not significantly elevated in smaller sample sets from patients with CMT2A, CMT2E, CMT1B, or CMT1X. The Olink immuno PCR assays confirmed elevated levels of NfL (average 1.58-fold, P < 0.0001), which correlated with CMT1A patient disease score. INTERPRETATION: These data identify the first Schwann cell-specific protein that is elevated in plasma of CMT1A patients, and may provide a disease marker and a potentially treatment-responsive biomarker with good disease specificity for clinical trials