448 research outputs found
Effects of genistein on melanosis and microbial quality of Litopenaeus vannamei during ice storage
Utilization of genistein as a natural inhibitor was studied alone and in combination with conventional treatments on melanosis and microbial quality of fresh L. vannamei during 10 days ice storage. Treatments were as followed: A (dipping samples in distilled water), B (dipping in 1.25 % sodium metabisulphite solution), C (dipping in 0.01 % genistein + 2% glycerol solution), D (dipping in 0.1 % genistein + 2% glycerol solution), E (dipping in 1% NaCl + 0.05 % EDTA + 0.5 % ascorbic acid + 0.5 % lactic acid solution), F (dipping in 0.01% genistein + 2 % glycerol + 1 % NaCl + 0.05 % EDTA + 0.5 % ascorbic acid + 0.5 % lactic acid solution) and G (dipping in 0.1 % genistein + 2 % glycerol + 1 % NaCl + 0.05 % EDTA + 0.5 % ascorbic acid + 0.5 % lactic acid solution). Results showed that G treatment was more affective on inhibiting of melanosis in L. vannamei. Mesophilic and psycrophilic bacterial counts in G treatment were lower than other treatments during ice storage
An investigation of a Æ”-type MTD Stirling engine prototype
This is the author accepted manuscript. The final version is available from UKACM via the link in this recordAlthough thermal efficiency of moderate temperature differential (MTD) Stirling engines is higher than
low temperature (LTD) engines, the complexity of design of MTD engines has led to the lack of research
in this field. In this work, a prototype of Æ”-type moderate-temperature differential Stirling engine was
manufactured, evaluated and structurally optimised. A mathematical evaluation was carried out based
on a finite-dimension thermodynamics approach. The swept volume ratio was optimised based on the
temperature difference of 450 .
0
. A computer program was thus written to simulate the Stirling engine
performance under the assumed working conditions. Based on the mentioned temperature difference,
the swept volume ratio of the engine was found to be 3. The engine dimensions were then adjusted to
fulfil the computed swept volume ratio. The bore and stroke for power piston were chosen as 60 mm
and 40 mm, respectively. For the displacer, they were selected as 90 mm and 60 mm, respectively
based on the chosen swept volume ratio
Inhibition of Drosophila Wg Signaling Involves Competition between Mad and Armadillo/β-Catenin for dTcf Binding
Precisely regulated signal transduction pathways are crucial for the regulation of developmental events and prevention of tumorigenesis. Both the Transforming Growth Factor β (TGFβ)/Bone morphogenetic protein (BMP) and Wnt/Wingless (Wg) pathways play essential roles in organismal patterning and growth, and their deregulation can lead to cancers. We describe a mechanism of interaction between Drosophila Wg and BMP signaling in which Wg target gene expression is antagonized by BMP signaling. In vivo, high levels of both an activated BMP receptor and the BMP effector Mad can inhibit the expression of Wg target genes. Conversely, loss of mad can induce Wg target gene expression. In addition, we find that ectopic expression in vivo of the Wg transcription factor dTcf is able to suppress the inhibitory effect caused by ectopic Mad. In vitro binding studies revealed competition for dTcf binding between Mad and the Wnt effector β-catenin/Armadillo (Arm). Our in vivo genetic analyses and target gene studies support a mechanism consistent with the in vitro binding and competition studies, namely that BMP pathway components can repress Wg target gene expression by influencing the binding of Arm and dTcf
Quantifying the pathway and predicting spontaneous emulsification during material exchange in a two phase liquid system
Kinetic restriction of a thermodynamically favourable equilibrium is a common theme in materials processing. The interfacial instability in systems where rate of material exchange is far greater than the mass transfer through respective bulk phases is of specific interest when tracking the transient interfacial area, a parameter integral to short processing times for productivity streamlining in all manufacturing where interfacial reaction occurs. This is even more pertinent in high-temperature systems for energy and cost savings. Here the quantified physical pathway of interfacial area change due to material exchange in liquid metal-molten oxide systems is presented. In addition the predicted growth regime and emulsification behaviour in relation to interfacial tension as modelled using phase-field methodology is shown. The observed in-situ emulsification behaviour links quantitatively the geometry of perturbations as a validation method for the development of simulating the phenomena. Thus a method is presented to both predict and engineer the formation of micro emulsions to a desired specification
Anti-amnesic activity of Citrus aurantium flowers extract against scopolamine-induced memory impairments in rats
Alzheimer's disease (AD) is a progressive neurological disorder that mostly affects the elderly population. Learning and memory impairment as the most characteristic manifestation of dementia could be induced chemically by scopolamine, a cholinergic antagonist. Cholinergic neurotransmission mediated brain oxidative stress. Citrus aurantium (CA) has traditionally been used for the treatment of insomnia, anxiety and epilepsy. The present study was designed to investigate the effect of Citrus aurantium on scopolamine-induced learning and memory deficit in rats. Forty-two Wistar rats were divided into six equal groups. (1) Control (received saline), (2) SCOP (scopolamine at a dose of 1 mg/kg for 15 days), (3) and (4) SCOP + CA (scopolamine and CA extract at doses of 300 and 600 mg/kg per day for 15 days), (5) and (6) intact groups (CA extract at 300 and 600 mg/kg per day for 15 days, respectively). Administration of CA flower extract significantly restored memory and learning impairments induced by scopolamine in the passive avoidance test and also reduced escape latency during trial sessions in the Morris water maze test. Citrus aurantium flower extract significantly decreased the serum malondialdehyde (MDA) levels. Citrus aurantium flower extract has repairing effects on memory and behavioral disorders produced by scopolamine and may have beneficial effects in the treatment of AD
The low abundance of CpG in the SARS-CoV-2 genome is not an evolutionarily signature of ZAP
The zinc finger antiviral protein (ZAP) is known to restrict viral replication by binding to the CpG rich regions of viral RNA, and subsequently inducing viral RNA degradation. This enzyme has recently been shown to be capable of restricting SARS-CoV-2. These data have led to the hypothesis that the low abundance of CpG in the SARS-CoV-2 genome is due to an evolutionary pressure exerted by the host ZAP. To investigate this hypothesis, we performed a detailed analysis of many coronavirus sequences and ZAP RNA binding preference data. Our analyses showed neither evidence for an evolutionary pressure acting specifically on CpG dinucleotides, nor a link between the activity of ZAP and the low CpG abundance of the SARS-CoV-2 genome
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