1,192 research outputs found
STABILITY OF BETACYANIN PIGMENTS FROM RED PURPLE PITAYA FRUIT (Hylocereus polyrhizus) : INFLUENCE OF PH, TEMPERATURE, METAL IONS AND ASCORBIC ACID
Betacyanin pigments from red-purple pitaya fruit (Hylocereus polyrhizus) could be an attractive source of red colourant for food application. This paper presents results on the extraction of betacyanin pigments from pitaya fruits grown locally in Malaysia. Both the flesh of the fruit and its mesocarp were investigated and it was found that the flesh had higher pigment contents compared to its peel component. The concentration of betacyanins expressed as betanin equivalents per 100 g of flesh and peel were 10.1 ± 0.6 mg and 6.7 ± 0.2 mg, respectively when 80% methanol was used. The stability of betacyanin pigments were investigated at different pH, temperature and in presence of different concentrations of metal ions (Cu2+ and Fe2+) and ascorbic acid. The results showed that the pigment was most stable at pH range between 5 and 6. However, it forfeited its stability to the heat induced at elevated temperatures. Metal ions (Cu2+ and Fe2+) proved to be capable of accelerating betacyanin degradation, with Cu2+ exhibiting the greatest effect. By contrast, supplementation with ascorbic acid could enhance the pigment stability against the detrimental effects caused by pH, temperature and metal ions. Nevertheless, if the concentration of ascorbic acid exceeds 0.7 %, it may change its role from pigment stabilizer to become a pro-oxidant.
Keywords: Betacyanin, pigments, pitaya fruit, Hylocereus polyrhizus, ascorbic aci
Characterization of Pneumatic Artificial Muscle System in an Opposing Pair Configuration
Pneumatic artificial muscle (PAM) is a pneumatic actuator that commonly used in the biomimetic robotic devices in rehabilitation applications due to its advantageous in high powerto-weight ratio and high degree of safety in use characteristics. Several techniques exist in the literature for the PAM system modeling, and these include theoretical modeling, phenomenological modeling and empirical modeling. This paper focuses on explaining the experimental setup of an opposing pair configuration of PAM system, and gives an analysis of the pneumatic muscle system dynamic in the theoretical modeling. The simulated dynamic model is compared with the actual PAM system for the validation in the open-loop step and sinusoidal positioning responses and pressures. It is concluded that the simulation result is verified and agreed with the actual system
Education in IT Security: A Case Study in Banking Industry
The banking industry has been changing incessantlyand facing new combination of risks. Data protection andcorporate security is now one of the major issues in bankingindustry. As the rapid changing on technologies from time totime, the industry should be aware on new technologies in orderto protect information assets and prevent fraud activities. Thispaper begins with literature study of information security issuesand followed by focused-group interviews with five participantswithin the industry and survey analysis of “The global state ofInformation Security survey 2013” which published byPriceWaterhouseCoopers (PWC). Trends and questions werediscussed as well as possible solution. The study suggests that ITsecurity education should be made to different level of staffs suchas executives, professional and general staffs. Besides, thebanking industry should increase company-wide securityawareness and the importance of corporate security which keepthe information and physical assets secure and in a proper way
Tracking Control of Vertical Pneumatic Artificial Muscle System Using PID
The advantages of pneumatic system such as compactness, high power to weight ratio, ease of maintenance, cleanliness and inherent safety led to the development of McKibben muscle and pneumatic artificial muscle (PAM). However, the air compressibility and the lack of damping ability of PAM bring dynamic delay to the pressure response and causes oscillatory motion to occur. It is not easy to realize the motion with high accuracy and high speed due to all the non-linear characteristics of pneumatic system. In this paper, we present a vertical PAM system with a simple PID controller to control the motion of the PAM. The experiment setup is explained and Ziegler Nichols tuning method is used in getting the approximation PID parameters. The effectiveness of the proposed control algorithm is demonstrated through experiments
Boron Fullerenes: A First-Principles Study
A family of unusually stable boron cages was identified and examined using
first-principles local density functional method. The structure of the
fullerenes is similar to that of the B12 icosahedron and consists of six
crossing double-rings. The energetically most stable fullerene is made up of
180 boron atoms. A connection between the fullerene family and its precursors,
boron sheets, is made. We show that the most stable boron sheets are not
necessarily precursors of very stable boron cages. Our finding is a step
forward in the understanding of the structure of the recently produced boron
nanotubes.Comment: 10 pages, 4 figures, 1 tabl
Full counting statistics of information content
We review connections between the cumulant generating function of full
counting statistics of particle number and the R\'enyi entanglement entropy. We
calculate these quantities based on the fermionic and bosonic path-integral
defined on multiple Keldysh contours. We relate the R\'enyi entropy with the
information generating function, from which the probability distribution
function of self-information is obtained in the nonequilibrium steady state. By
exploiting the distribution, we analyze the information content carried by a
single bosonic particle through a narrow-band quantum communication channel.
The ratio of the self-information content to the number of bosons fluctuates.
For a small boson occupation number, the average and the fluctuation of the
ratio are enhanced.Comment: 16 pages, 5 figure
Testing a Family Supportive End of Life Care Intervention in a Chinese Neonatal Intensive Care Unit: A Quasi-experimental Study With a Non-randomized Controlled Trial Design
Background: Neonatal death often occurs in tertiary Neonatal Intensive Care Units (NICUs). In China, end-of-life-care (EOLC) does not always involve parents. Aim: The aim of this study is to evaluate a parent support intervention to integrate parents at the end of life of their infant in the NICU. Methods: A quasi-experimental study using a non-randomized clinical trial design was conducted between May 2020 and September 2021. Participants were infants in an EOLC pathway in the NICU and their parents. Parents were allocated into a family supportive EOLC intervention group or a standard EOLC group based on their wishes. The primary outcomes depression (Edinburgh Postnatal Depression Scale for mothers; Hamilton Depression rating scale for fathers) and Satisfaction with Care were measured 1 week after infants' death. Student t-test for continuous variables and the Chi-square test categorical variables were used in the statistical analysis. Results: In the study period, 62 infants died and 45 infants and 90 parents were enrolled; intervention group 20 infants, standard EOLC group 25 infants. The most common causes of death in both groups were congenital abnormalities (n = 20, 44%). Mean gestational age of infants between the family supportive EOLC group and standard EOLC group was 31.45 vs. 33.8 weeks (p = 0.234). Parents between both groups did not differ in terms of age, delivery of infant, and economic status. In the family support group, higher education levels were observed among mother (p = 0.026) and fathers (p = 0.020). Both mothers and fathers in the family supportive EOLC group had less depression compared to the standard EOLC groups; mothers (mean 6.90 vs. 7.56; p = 0.017) and fathers (mean 20.7 vs. 23.1; p < 0.001). Parents reported higher satisfaction in the family supportive EOLC group (mean 88.9 vs. 86.6; p < 0.001). Conclusions: Supporting parents in EOLC in Chinese NICUs might decreased their depression and increase satisfaction after the death of their infant. Future research needs to focus on long-term effects and expand on larger populations with different cultural backgrounds. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT05270915
Scaling predictions for radii of weakly bound triatomic molecules
The mean-square radii of the molecules He, HeLi,
HeLi and HeNa are calculated using a three-body model
with contact interactions. They are obtained from a universal scaling function
calculated within a renormalized scheme for three particles interacting through
pairwise Dirac-delta interaction. The root-mean-square distance between two
atoms of mass in a triatomic molecule are estimated to be of de order of
, where is the dimer and the
trimer binding energies, and is a constant (varying from
to ) that depends on the ratio between and . Considering
previous estimates for the trimer energies, we also predict the sizes of
Rubidium and Sodium trimers in atomic traps.Comment: 7 pages, 2 figure
Spectral method for the time-dependent Gross-Pitaevskii equation with a harmonic trap
We study the numerical resolution of the time-dependent Gross-Pitaevskii
equation, a non-linear Schroedinger equation used to simulate the dynamics of
Bose-Einstein condensates. Considering condensates trapped in harmonic
potentials, we present an efficient algorithm by making use of a spectral
Galerkin method, using a basis set of harmonic oscillator functions, and the
Gauss-Hermite quadrature. We apply this algorithm to the simulation of
condensate breathing and scissors modes.Comment: 23 pages, 5 figure
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