110 research outputs found
Scale-up thermostable α-amylase production in lab-scale fermenter using rice husk as an elicitor by Bacillus licheniformis-AZ2 isolated from Qinarje Hot Spring (Ardebil Prov. of Iran)
Background and purpose: Amylases are commercially important enzymes with various biotechnological, clinical and medical applications. This study aimed at scaling up α-amylase production elicited by rice husk in stirred-fermenter using Bacillus lichneniformis-AZ2 isolated from Qinarje Hot Spring.
Materials and methods: Effect of temperature, aeration rate and agitation speed on bacterial growth and É-amylase production were investigated under batch fermentation process in a 3-Lit stirred-fermenter. OFAT method was followed to select optimum level of each parameter. Other factors were set upon the results of previous experiments carried out in shake-flask scale.
Results: Maximum α-amylase production of 17.66 ± 0.87 U/mL (2.1 folds more than shake-flask cultures) was achieved in stirred-fermenter with optimized agitation speed of 100 rpm and 1 vvm aeration rate at 37ÂșC after 60 h of incubation. This time was shorter than the corresponding fermentation time obtained from shake-flask experiments by half. A comparison of kinetic parameters of fermentation in stirred-fermenter and shake-flask cultures revealed that B. licheniformis-AZ2 was more active to synthesize É-amylase in fermenter. In shaken cultures Qx, Qp, Yp/x, ”max, qp and td, were 0.27 (g/L/h), 228.6 (U/L/h), 13.64 (U/g), 0.055 (h-1), 0.76 (U/g/h) and 12.48 h, whereas in stirred-fermenter the above values were 0.40 (g/L/h), 723.1 (U/L/h), 45.17 (U/g), 0.120 (h-1), 5.42 (U/g/h) and 5.78 h, respectively.
Conclusions: SmF in stirred-fermenter is a potential strategy for É-amylase production. Although for commercialization further studies are needed in pilot-scale. Rice husk as a low-cost agro-waste is preferable to use as the carbon and energy sources, which provides a great É-amylase elicitation.</p
Anti-inflammatory and anti-nociceptive effects of extract contains and without Glycyrrhizic acid of Glycyrrhiza glabra rhizome in male mice
Background and aims: Glycyrrhiza glabra L. (licorice) is a very sweet and soothing herb with anti-inflammatory property and hormonal effects, and in the high importance to the pharmaceutical and food industries. The aim of this study was to investigate the Anti-inflammatory and analgesic effects of extract containing and without Glycyrrhizic acid of licorice rhizome on small laboratory mice.
Methods: In this experimental study, 126 male NMRI mice randomly divided into 18 groups (n=7). Xylene and Formalin Tests used for demonstrating anti-inflammatory and antinociceptive effects. The normal saline control group and the positive control group in the inflammation test were injected dexamethasone, and morphine was injected in the pain test. Experimental groups received extract with and without Glycyrrhizic acid of licorice rhizome at doses of 20, 40, 60, 90 and 120 mg/kg. Statistical analysis was performed using Graph pad Prism software, one and two way ANOVA and Tukeyâs post-hoc tests (P<0.05).
Results: The results of inflammation test showed that all doses of extract with glycyrrhizin contain anti-inflammatory effect in inhibiting the xelen-induced inflammation compared with the control group. Results of formalin test showed that the extract with glycyrrhizin has more analgesic effect than without glycyrrhizin extract. Analgesic effects of two extracts in both acute and chronic pain were observed which the pain score dropped significantly in chronic pain.
Conclusion: Findings of this study showed that licorice root extract has analgesic and anti-inflammatory effects so that major part of these effects is probably related to Glycyrrhizic acid
Downregulation of Sirt1 is correlated to upregulation of p53 and increased apoptosis in epicardial adipose tissue of patients with coronary artery disease
The higher expression level of p53 in epithelial adipose tissue (EAT) has previously been reported in atherosclerosis. Since we hypothesized that the expression of p53 is modulated by Sirt1, the aim of this study was to determine the expression levels of Sirt1 and p53 and to investigate their correlation to apoptosis in EAT of patients with coronary artery disease (CAD). Thirty-five patients with more than 50 % stenosis in at least one of the main coronary arteries were considered as CAD group while 29 patients with no clinical signs of atherosclerosis who underwent open-heart surgery for valve replacement were classified as control group. EAT biopsy samples were collected from all participants during surgery. Sirt1, p53, Bax, and Bclâ2 gene expression levels were determined in EAT by qRT-PCR and Western blotting was carried out to assess Sirt1 and p53 protein levels. Hematoxylin and eosin staining was used for histopathological analysis. mRNA and protein levels of Sirt1 in EAT were significantly lower in patients with CAD compared with control group, whereas CAD patients showed greater p53 gene and protein expressions. In addition, inverse correlations were observed between Sirt1 and p53 at both mRNA and protein levels. The Bax and ratio of Bax/Bcl-2 gene expressions were higher in CAD group, but no difference was observed in Bcl-2 expression. Histopathological analysis showed apoptotic bodies and infiltrated immune cells in EAT of CAD group. Our results suggest that the Sirt1-p53 axis may involve in atherosclerosis by promotion of apoptosis
Estimating Oil Price Volatility Using Stochastic Volatility (SV) and Its Impact on Corporate Investment
Firm investment is one of the important financial decisions in the economy, which affects the value of companies and the wealth of shareholders, which can result in increasing welfare. Despite neglecting the effects of uncertainty in traditional investment theories, modern theories have introduced various mechanisms for the impact of uncertainty on investment expenditures. Using the daily data of oil prices and the data of 131 companies listed on the Tehran Stock Exchange market during the period of 2008-2020, the factors affecting the investment of the companies are identified by emphasizing the oil price uncertainty. For this purpose, in the first step, the stochastic volatility model in the framework of the space-state approach is the basis for estimating the oil price uncertainty, and in the next, according to the results of the Hausman endogeneity test, the instrumental variable method is used to estimate the coefficients of the variables affecting investment. The findings indicate that first, the volatility of oil prices has no significant effect on investment. Second, firm size, profitability, inflation, and Tobinâs Q affect investment positively and significantly. Third, the financial leverage, which is reflected in the capital structure polices, has a significant negative effect on investment, meaning that more focus on debt financing leads to less corporate investment expenditures
IsomiRs: A New Approach to Cancer Study
microRNAs are regulatory non-coding RNA molecules that containing about 18-24 nucleotides which involved in critical steps of many cellular processes, specifically gene expression, therefore, their deregulation can lead to human tumorigenesis. some kinds of variants of microRNAs are isomiRs that their length or sequence varies from miRNAs and they commonly araised from diverse cleavage by the ribonucleases Drosha and Dicer. Recent reports confirm that some of isomiRs may be yielded from a miRNA locus, and these physiological mature isomers have important roles in miRNA evolution. In this research, we reviewed new field of miRNAs structural /sequence diversity that can be involved in cancer biology. Also describe the evolutionary approaches and the functional significance of the miRNAs isoforms; however, there are lots of isomiR/miRNA molecular mechanisms that remain unclear. More studies to reveal more insights of functionality isomiRs into the carcinogenesis will provide informative strategies to be used in prognosis, diagnosis or treatment
Parameter estimation by learning quantum correlations in continuous photon-counting data using neural networks
We present an inference method utilizing artificial neural networks for
parameter estimation of a quantum probe monitored through a single continuous
measurement. Unlike existing approaches focusing on the diffusive signals
generated by continuous weak measurements, our method harnesses quantum
correlations in discrete photon-counting data characterized by quantum jumps.
We benchmark the precision of this method against Bayesian inference, which is
optimal in the sense of information retrieval. By using numerical experiments
on a two-level quantum system, we demonstrate that our approach can achieve a
similar optimal performance as Bayesian inference, while drastically reducing
computational costs. Additionally, the method exhibits robustness against the
presence of imperfections in both measurement and training data. This approach
offers a promising and computationally efficient tool for quantum parameter
estimation with photon-counting data, relevant for applications such as quantum
sensing or quantum imaging, as well as robust calibration tasks in
laboratory-based settings.Comment: 15 pages, 8 figures, code is available at
http://github.com/CarlosSMWolff/ParamEst-N
Effects of different nutritional systems on seed germination and early seedling growth in medicinal pumpkin (Cucurbita pepo L.)
This study was carried out to
determine the effect of different nutritional
systems (chemical, biological and
integrated) on germination and seedling
growth in medicinal pumpkin (Cucurbita
pepo L.). The statistical design was a
randomized complete block design with
four replications. Four levels of different
fertilizing systems including chemical (T1),
biological (a combination of nitrogen
bacteria, Azospirillum brasilense and
Glomus mosseae) (T2) and integrated
fertilizing systems (biological fertilizer +
50% chemical fertilizer) (T3), and control
(without fertilizer) (T0), were employed.
The results indicated that the maximum seed
germination was 95% and the highest seed
germination rate with 30.4 per day was
observed in the intergraded nutritional
treatment. The experimental results showed
that all nutritional treatments had positive
effects on seed germination compared to
control. The highest level of germination
percentage with 95% and the highest rate of
germination with 30.4 seeds per day were
obtained in integrated nutritional treatment.
However, the integrated nutritional system
required more time to demonstrate its
positive effect on the growth and yield of
medicinal pumpkin compared to chemical
system. The results of present experiment
indicated that integrated nutritional
treatment had the greatest positive impact
on germination characteristics in medicinal
pumpkin. Designing and developing such
nutritional systems can guarantee and
facilitate the achievement of long-term
objectives of sustainable agriculture
Universal control of a bosonic mode via drive-activated native cubic interactions
Linear bosonic modes offer a hardware-efficient alternative for quantum
information processing but require access to some nonlinearity for universal
control. The lack of nonlinearity in photonics has led to encoded
measurement-based quantum computing, which rely on linear operations but
requires access to resourceful ('nonlinear') quantum states, such as cubic
phase states. In contrast, superconducting microwave circuits offer
engineerable nonlinearities but suffer from static Kerr nonlinearity. Here, we
demonstrate universal control of a bosonic mode composed of a superconducting
nonlinear asymmetric inductive element (SNAIL) resonator, enabled by native
nonlinearities in the SNAIL element. We suppress static nonlinearities by
operating the SNAIL in the vicinity of its Kerr-free point and dynamically
activate nonlinearities up to third order by fast flux pulses. We
experimentally realize a universal set of generalized squeezing operations, as
well as the cubic phase gate, and exploit them to deterministically prepare a
cubic phase state in 60 ns. Our results initiate the experimental field of
universal continuous-variables quantum computing.Comment: 11 pages, 6 figures and supplementary material
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