The progenitors of Type Ia supernovae with long delay times

The nature of the progenitors of Type Ia supernovae (SNe Ia) is still unclear. In this paper, by considering the effect of the instability of accretion disk on the evolution of white dwarf (WD) binaries, we performed binary evolution calculations for about 2400 close WD binaries, in which a carbon--oxygen WD accretes material from a main-sequence star or a slightly evolved subgiant star (WD + MS channel), or a red-giant star (WD + RG channel) to increase its mass to the Chandrasekhar (Ch) mass limit. According to these calculations, we mapped out the initial parameters for SNe Ia in the orbital period--secondary mass ($\log P^{\rm i}-M^{\rm i}_2$) plane for various WD masses for these two channels, respectively. We confirm that WDs in the WD + MS channel with a mass as low as $0.61 M_\odot$ can accrete efficiently and reach the Ch limit, while the lowest WD mass for the WD + RG channel is $1.0 \rm M_\odot$. We have implemented these results in a binary population synthesis study to obtain the SN Ia birthrates and the evolution of SN Ia birthrates with time for both a constant star formation rate and a single starburst. We find that the Galactic SN Ia birthrate from the WD + MS channel is $\sim$$1.8\times 10^{-3} {\rm yr}^{-1}$ according to our standard model, which is higher than previous results. However, similar to previous studies, the birthrate from the WD + RG channel is still low ($\sim$$3\times 10^{-5} {\rm yr}^{-1}$). We also find that about one third of SNe Ia from the WD + MS channel and all SNe Ia from the WD + RG channel can contribute to the old populations (\ga1 Gyr) of SN Ia progenitors.Comment: 11 pages, 9 figures, 1 table, accepted for publication in MNRA

The Relationship between Fungal Growth Rate and Temperature and Humidity

In order to determine the relation among the three factors of wood fiber decomposition rate, mycelial elongation and moisture resistance, our team resorted to the Monod equation and the modified Logistic equation. Combing with the kinetic principle and the law of mass action, the equations between the decomposition rate of wood fiber, the elongation rate of mycelium and the moisture resistance were established. In the course of solving the model, we found that when the temperature ranges from 24℃ to 28℃ and the relative humidity from 60% to75%, the growth rate of fungi is the fastest

Dynamic Booking Control for Car Rental Revenue Management : A Decomposition Approach

This paper considers dynamic booking control for a single-station car rental revenue management problem. Different from conventional airline revenue management, car rental revenue management needs to take into account not only the existing bookings but also the lengths of the existing rentals and the capacity flexibility via fleet shuttling, which yields a high-dimensional system state space. In this paper, we formulate the dynamic booking control problem as a discrete-time stochastic dynamic program over an infinite horizon. Such a model is computationally intractable. We propose a decomposition approach and develop two heuristics. The first heuristic is an approximate dynamic program (ADP) which approximates the value function using the value functions of the decomposed problems. The second heuristic is constructed directly from the optimal booking limits computed from the decomposed problems, which is more scalable compared to the ADP heuristic. Our numerical study suggests that the performances of both heuristics are close to optimum and significantly outperform the commonly used probabilistic non-linear programming (PNLP) heuristic in most of the instances. The dominant performance of our second heuristic is evidenced in a case study using sample data from a major car rental company in the UK

Analysis on the Influence of Price, Product, and Advertisement on the Purchasing Decision of Indomie Instant Noodle

This study aims to determine and analyze the influence of price, advertisement, and product quality on Indomie instant noodle purchasing decisions. The researcher collects the data online in the city of Jakarta. Due to limited time and money, some of the existing populations were taken to be the sample in the study. Due to limited time and funds, the researcher determined the number of samples in this study as many as 200 respondents. Data were collected by spreading the questionnaires online by using Google Form, the variables studied were using a Likert scale. The list of questions was first tested using validity and reliability testing, then analysed by classic assumption test and hypothesis test using SPSS software. Simultaneously, the variables of price, advertisement, and product quality have a significant effect on the purchasing decision of Indomie instant noodles. Keywords: Price, Advertisement, Product, Purchasing Decision DOI: 10.7176/JESD/12-6-03 Publication date:March 31st 202

Applying the scientific method to understand anomalous heat effect

Abstract only.Scientific methods in nuclear science are proposed to understand anomalous heat effect: (1) Neutrino Detection; (2) Internal Conversion Electrons; (3) RF emission and magnetic field fluctuation; (4) 3-Deuteron reaction; (5) Solid State Nuclear Track Detector(CR-39); (6) 6Li+p resonance at low energy. Each topic will be discussed in order

Farrerol ameliorates diabetic hepatopathy in rat model of type 2 diabetes mellitus via modulation of oxidativeinflammatory stress

Purpose: To investigate the effect of farrerol on diabetic hepatopathy in a rat model of type 2 diabetes mellitus (T2DM).Methods: Adult male Wistar rats (n = 40) were randomly assigned to four groups of ten rats each: normal control, diabetic control, farrerol control and treatment groups. With the exception of normal control and farrerol control groups, the rats were fed high-fat diet (HFD) for four weeks, and thereafter injected streptozotocin (STZ) at a dose of 30 mg/kg body weight intraperitoneally (i.p.) for induction of T2DM. Rats in farrerol control and treatment groups received 50 mg/kg farrerol orally/day. Serum levels of triacylglycerol (TG), total cholesterol (TC), high-density lipoprotein  cholesterol (HDL-C) and lowdensity lipoprotein cholesterol (LDL-C) were determined. Superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels were assessed in liver homogenate while mRNA and protein expressions of glucose transporter 2 (GLUT2) were assayed in liver using real-time quantitative polymerase chain reaction (qRT-PCR) and Western blotting, respectively. Expression levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were also determined using qRT-PCR.Results: Diabetes mellitus (DM) led to significant reductions in rat body weight and SOD activity, while increasing fasting blood glucose (FBG) and MDA levels (p < 0.05). However, treatment with farrerol significantly reversed the effect of DM on these parameters (p < 0.05). The mRNA expressions of TNF-α and IL-1β were significantly higher in diabetic control group than in normal control group, but were significantly reduced after farrerol treatment (p < 0.05). Treatment with farrerol also significantly reversed the effect of DM on rat lipid profile (p < 0.05). The expression of GLUT2 protein was significantly downregulated in the liver of diabetic control rats, when compared with normal control rats, but was significantly upregulated after treatment with farrerol (p < 0.05).Conclusion: The results of this study show that farrerol alleviates STZ-induced hyperglycemia and dyslipidemia via reduction in oxidative stress and inflammation, and upregulation of GLUT2 protein expression. Thus, farrerol has antidiabetic and hepatoprotective potentials for clinical use in  humans. Keywords: Diabetes mellitus, Dyslipidemia, Farrerol, Hepatopathy, High-fat die

Modeling branching effects on source-sink relationships of the cotton plant

International audienceCompared with classical process-based models, the functional-structural plant models provide more efficient tools to explore the impact of changes in plant structures on plant functioning. In this paper we investigated the effects of branches on the sourcesink interaction for the cotton plant (Gossypium hirsutum L.) based on a two-treatment experiment conducted on cotton grown in the field: the singlestem plants and the plants with only two vegetative branches. It was observed that the branched cotton had more organs for the whole plant but the organs on the trunk were smaller than those on the single-stem cotton. The phytomer production of the branches was four or five growth cycles delayed compared with the main stem. The organs on the trunk had similar dynamics of expansion for both treatments. Effects of branches were evaluated by using the functionalstructural model GREENLAB. It allowed estimating the coefficients of sink strength to differentiate the biomass acquisition abilities of organs between different physiological ages. We found that the presence of the two vegetative branches increased the ground projection area of plant leaves and had led to slight changes on the directly measured parameters; the potential relative sink strengths of organs were found similar for the two treatments

Poly[[bis(μ2-4-amino­benzene­sul­fon­ato-κ2 N:O)diaqua­manganese(II)] dihydrate]

The title compound, {[Mn(NH2C6H4SO3)2(H2O)2]·2H2O}n, was prepared under mild hydro­thermal conditions. The unique MnII ion is located on a crystallographic inversion center and is coordinated by two –NH2 and two –SO3 groups from four 4-amino­benzene­sulfonate ligands and by two water mol­ecules in the axial positions, forming a slightly distorted octa­hedral coordination environment. The 4-amino­benzene­sulfonate anions behave as μ2-bridging ligands to produce a two-dimensional structure. In the crystal structure, inter­molecular N—H⋯O, O—H⋯O and C—H⋯O hydrogen bonds link the layers into a three-dimensional network

The application research on improvement of genetic algorithm in linear CCD detection

When the linear array image sensor (CCD) is used for spot detection, the optimization of the detection signal is usually one of the problems that plague the user. In linear array imaging sensor (CCD) detection applications, optimization of the detection signal is usually one of the problems with the user. Based on the characteristics of linear array CCD detection signal, a genetic algorithm (GA) is established to solve the problem of mathematical model. In this paper, a new adaptive genetic algorithm (IGA) with directional adaptive guidance and adaptive control technology and threshold constraint technology are proposed for the lack of local optimization ability of the standard genetic algorithm (SGA), premature convergence and low accuracy. By applying IGA to the actual detection data, it is proved that IGA has certain advantages in solving the problem of linear CCD detection signal optimization. In the end of this paper, the performance of IGA, SGA and peak finding algorithm (SP) are analyzed and compared, which fully demonstrates the advantages of IGA in solving such problems