Histamine Levels in Commercially Processed Fish in Morocco

1986 ◽  
Vol 49 (11) ◽  
pp. 904-908 ◽  
Author(s):  
L. ABABOUCH ◽  
M.M. ALAOUI ◽  
F.F. BUSTA
Keyword(s):  
Shelf Life ◽  
Regional Differences ◽  
Reaction Rates ◽  
Mean Value ◽  
Tuna Fish ◽  
Fresh Fish ◽  
First Order ◽  
First Order Kinetics ◽  
Fish Samples ◽  
The Mean

Histamine levels were determined in 248 samples of fish commercially processed in Morocco. Concentrations ranging from <0.01 to 694 mg/100 g of fish (mg%) were observed. The mean value was 12.33 mg% (sardines, 9.75; mackerel, 13.74; tuna 9.86) and the standard deviation was 55.28 mg% (sardines, 43.21; mackerel, 71.99; tuna, 25.05). The bulk of the samples (85.5%) had low histamine levels (<10 mg%); 26 samples (10.5%) had levels within the range 10–50 mg% and should be classified as not from fresh fish or of low quality; 10 samples (4%) had toxicologically significant levels, above 50 mg%. Tuna fish was more susceptible to histamine development than were sardines or mackerel; 7% of tuna fish samples contained levels above 50 mg% as compared to 3.7% and 3.2% for sardines and mackerel, respectively. The percentage of samples containing levels above 50 mg% was somewhat higher for fish processed in the central region (7.1%) than the southern (4.3%) or northern (1.3%) regions; however, statistically the regional differences were not significantly different. Histamine development in sardines demonstrated first-order kinetics. Reaction rates ranged from 0.00200 to 0.000421 mn−1. Refrigeration controlled histamine development. Fish held at 8°C showed a shelf life 12 h longer than fish held at 17°C. A combination of salting and refrigeration was more effective. Fish held at 8°C and salted at a level of 5 or 8% showed a shelf life 35 h longer than fish held at 17°C with no salt.

Unified uncertainty analysis by the mean value first order saddlepoint approximation

2012 ◽  
Vol 46 (6) ◽  
pp. 803-812 ◽  
Author(s):  
Ning-Cong Xiao ◽  
Hong-Zhong Huang ◽  
Zhonglai Wang ◽  
Yu Liu ◽  
Xiao-Ling Zhang
Keyword(s):  
Uncertainty Analysis ◽  
Saddlepoint Approximation ◽  
Mean Value ◽  
First Order ◽  
The Mean

Characterization of a Fibrin Glue-Gdnf Slow-Release Preparation

1998 ◽  
Vol 7 (1) ◽  
pp. 53-61
Author(s):  
Henrich Cheng ◽  
Matt Fraidakis ◽  
Birger Blombäck ◽  
Paul Lapchak ◽  
Barry Hoffer ◽  
...  
Keyword(s):  
Linear Regression ◽  
Least Squares ◽  
Fibrin Glue ◽  
Trophic Factor ◽  
Adult Rats ◽  
First Order ◽  
First Order Kinetics ◽  
Implantation Sites ◽  
The Mean ◽  
Over Time

One novel method to deliver trophic factor locally in the CNS is to mix it into fibrin glue. In the present studies, [125I]-labeled GDNF-containing fibrin glue balls were used to determine binding and spread of the trophic factor. First, the binding of different concentrations of [125I]-labelèd GDNF in fibrin glue was determined in vitro. Within the six concentrations used (from 200 nM to 0.004 nM, 0 M as control), there was a strong linear correlation between the [125I]-GDNF concentration and the recovered radioactivity (r = 0.992). The mean bound radioactivity in 16 samples with 4 nM [125I]-GDNF was 71262 + 2710 CPM, and accounted for 89.8% of the mean initial count of free [125I]-GDNF (79369 + 3499 CPM). Second, [125I]-GDNF-containing glue balls were implanted into the anterior chamber of adult rats. The implanted fibrin glue balls decreased in size with time, but could still be identified on the irises 2 wk after implantation. Radioactivity was concentrated at the implantation sites in the early stages with a distribution in the surrounding iris tissue, which became separated into focal radioactive spots at the third week. Counts of radioactivity were significantly higher in the [125I]-GDNF glue ball-implanted irises than controls until 14 days after implantation. A study of the [125I] decay over time using least-squares linear regression demonstrated first-order kinetics (r = —0.98, p < 0.02) with k = 0.0091 and T 1/2 = 76 h. Finally, [125I]-GDNF–containing glue balls were implanted in the spinal cord of adult rats. Radioactivity was concentrated at the implantation sites in the early stages and was later distributed more widely in the surrounding thoracic cord. The [125I]-GDNF–containing glue degraded over time and became a porous meshwork with decreasing radioactivity at the later time points. Radioactivity in the spinal cords subjected to implantation of [125I]-GDNF–containing glue balls was higher than in controls for 14 days. Study of the [125I] decay by time with least-squares linear regression demonstrated first-order kinetics (r = -0.97, p = 0.001) with T 1/2 = 75.6 h. We conclude that the trophic factor GDNF becomes bound in the fibrin glue matrix from which it is gradually released. Our results suggest that fibrin glue is an effective substrate for keeping a trophic factor localized in situ for a finite period, protected from the circulation, surrounding aqueous humor or CSF.

scholarly journals CATION EXCHANGE BETWEEN CELLS AND PLASMA OF MAMMALIAN BLOOD

1950 ◽  
Vol 33 (6) ◽  
pp. 703-722 ◽  
Author(s):  
C. W. Sheppard ◽  
W. R. Martin
Keyword(s):  
Exchange Rate ◽  
Radioactive Isotope ◽  
Specific Activity ◽  
Compartment System ◽  
First Order ◽  
First Order Kinetics ◽  
Mammalian Blood ◽  
The Mean ◽  
Pseudo First Order

The exchange of potassium between cells and plasma of heparinized human blood has been studied in vitro using the radioactive isotope K42. The changes in cell and plasma specific activity are characteristic of a simple two-compartment system. The mean of seven determinations of the exchange rate at 38°C. is 1.8 per cent of the cellular potassium per hour. The results indicate that at 38°C. the rate is relatively insensitive to oxygenation or reduction of the hemoglobin, and to 1200 r of gamma radiation. With varying temperature the rate follows pseudo first order kinetics with a Q10 of 2.35. Below 15°C. the rate of loss of potassium exceeds the rate of uptake.

scholarly journals A New Conformable Fractional Derivative and Applications

2021 ◽  
Vol 2021 ◽  
pp. 1-5
Author(s):  
Ahmed Kajouni ◽  
Ahmed Chafiki ◽  
Khalid Hilal ◽  
Mohamed Oukessou
Keyword(s):  
Fractional Derivative ◽  
Fractional Derivatives ◽  
Mean Value ◽  
Mean Value Theorem ◽  
Conformable Fractional Derivative ◽  
First Order ◽  
Rolle’S Theorem ◽  
Power Rule ◽  
The Mean ◽  
Definition Of

This paper is motivated by some papers treating the fractional derivatives. We introduce a new definition of fractional derivative which obeys classical properties including linearity, product rule, quotient rule, power rule, chain rule, Rolle’s theorem, and the mean value theorem. The definition D α f t = lim h ⟶ 0 f t + h e α − 1 t − f t / h , for all t > 0 , and α ∈ 0,1 . If α = 0 , this definition coincides to the classical definition of the first order of the function f .

scholarly journals Comparative analysis of brain in relation to the body length and weight of common carp (Cyprinus carpio) in captive (hatchery) and wild (river system) populations

2022 ◽  
Vol 82 ◽  
Author(s):  
W. Khan ◽  
M. I. Khan ◽  
S. Hussain ◽  
Z. Masood ◽  
M. Shadman ◽  
...  
Keyword(s):  
Common Carp ◽  
Cyprinus Carpio ◽  
Wild Population ◽  
Brain Size ◽  
River System ◽  
Mean Value ◽  
The Body ◽  
Brain Weight ◽  
Fish Samples ◽  
The Mean

Abstract Cyprinus carpio is the member of family cyprinidae commonly called common carp. This study was aimed to find out the comparison of brain of wild (river system) and captive (hatchery reared) population of common carp. A total of thirty samples (15 from hatchery and 15 from river Swat) were collected. All the specimens were examined in Laboratory of Parasitoloy, Zoology Department, University of Malakand. Findings indicated that wild population were greater in brain size and weight as compared to hatchery reared population. The fish samples collected from captive environment (hatchery) were showing more weight and length as compared to wild population of common carps. The mean value of total weight of hatchery fishes 345±48.68 and the mean value of brain weight of hatchery reared fishes 0.28±0.047. The mean value of wild fish’s total body weight 195.16±52.58 and the mean value of brain weight of wild fishes are 0.45±0.14. Present research calls for the fact that fish in dependent environmental conditions possess brain larger in size as compared to its captive population, it is due to use and disuse of brain in their environmental requirements.

scholarly journals On the Accuracy of Error Propagation Calculations by Analytic Formulas Obtained for the Inverse Transformation

2019 ◽  
Vol 64 (3) ◽  
pp. 217
Author(s):  
V. I. Romanenko ◽  
N. V. Kornilovska
Keyword(s):  
Error Propagation ◽  
Random Variable ◽  
Mean Value ◽  
Inverse Transformation ◽  
First Order ◽  
Order Of Magnitude ◽  
The Mean ◽  
Normally Distributed

The accuracy of error propagation calculations is estimated for the transformation x → y = f(x) of the normally distributed random variable x. The estimation is based on the formulas for the error propagation obtained for the inverse transformation y → x of the normally distributed random variable y. In the general case, the calculation accuracy for the mean value and the variance of the random variable y is shown to be of the first order of magnitude in the variance of the random variable x.

Assessment of quality and safety of traditional smoked spotted tilapia fish (Tilapia mariae) from Lagos State, Nigeria

2016 ◽  
Vol 46 (1) ◽  
pp. 142-155 ◽  
Author(s):  
Samuel Ayofemi Adeyeye ◽  
Olusola Bandele Oyewole ◽  
Adewale Olusegun Obadina ◽  
A M Omemu ◽  
O E Adeniran ◽  
...  
Keyword(s):  
Fat Content ◽  
Microbial Safety ◽  
Microbial Infection ◽  
Content Type ◽  
Fresh Fish ◽  
Smoked Fish ◽  
Fish Samples ◽  
Lagos State ◽  
The Mean ◽  
Microbiological Analyses

Purpose – This study aims to assess the quality and microbial safety of traditional smoked spotted tilapia fish from Lagos State and, by doing so, determine the quality and microbial safety level of traditional smoked spotted tilapia fish, their distribution, effects and possible public health implications of the quality/rancidity indices and microorganisms on the consumers. Design/methodology/approach – Fresh spotted tilapia fish (100 samples) were collected from 20 different fishing/processing centres and divided into two batches. One batch was smoked with local drum kiln at processing centres, and the second batch was smoked with convective smoking kiln as control in the laboratory. Each batch was assessed for moisture content, protein content, fat content, crude fibre content, ash content, pH, thiobarbituric acid (TBA), total volatile base- nitrogen (TVB-N), trimethylamine (TMA), peroxide value (PV) and free fatty acid (FFA) values. Microbiological analyses were also conducted. Each batch was assessed for total viable count (TVC), fungal count, Listeria monocytogenes count, Staphylococcus aureus count, Salmonella paratyphi count and presence or absence of Escherichia coli. Findings – The results of the proximate composition, quality indices and microbiological analyses revealed that there was significant variations (p < 0.05) between smoked fish with different smoking methods. The mean pH, TBA, TVB-N, TMA, PV and FFA values of fresh and smoked spotted tilapia fish samples were within the range recommended by United States Food and Drug Administration. The mean TVC of fresh spotted tilapia fish samples was 6.3 × 106-8.8 × 108 cfu/g and TVC of samples of smoked spotted tilapia fish and the control were 2.0 × 104-6.4 × 104 cfu/g and 1.0 × 103-8.6 × 103 cfu/g, respectively. The mean L. monocytogenes count of fresh spotted tilapia fish samples was 1.3 × 102-2.4 × 102 cfu/g and that of samples of smoked spotted tilapia fish ranged from 1.6 × 101 to 23.1 × 101 cfu/g while samples of smoked spotted tilapia fish using convective smoking kiln showed no count for L. monocytogenes. The mean S. aureus count of fresh spotted tilapia fish samples ranged from 4.7 × 103 to 8.0 × 103 cfu/g and that of samples of smoked spotted tilapia fish ranged from 5.1 × 102 to 88.6 × 102 cfu/g and 1.1 × 102 to 3.8 × 102 cfu/g. The mean fat content (FC) count of samples of smoked spotted tilapia fish ranged from 1.1 × 101 to 6.0 × 101 cfu/g. S. paratyphi and E. coli were not detected in all smoked spotted tilapia fish samples. The study, however, concluded that the traditional drum smoked spotted tilapia fish could expose consumers to high microbial risk because of the presence of L. monocytogenes. Research limitations/implications – The fresh fish used in this study were obtained from coastal villages in Lagos State, and there were limitations in getting the samples in time to the processing centres and in preserving the fresh fish because of poor or non-availability of power (electricity). Practical implications – The paper includes implications for the development of a cost-effective smoked fish, to ensure food safety, enhanced health and improve the preservation and post-harvest losses of fresh fish. Social implications – The paper helps in developing an effective smoked method that will produce good-quality smoked fish, reduce the incidence of food poison and enhance the health of consumers. Originality/value – This research is of value to the traditional fish smokers and consumers. Smoked fish has been implicated as a source of microbial infection in Nigeria and West African sub-region in recent times and the need for good manufacturing practices cannot be overemphasized.

The mean value theorems and a Nagumo-type uniqueness theorem for Caputo’s fractional calculus

2012 ◽  
Vol 15 (2) ◽  
Author(s):  
Kai Diethelm
Keyword(s):  
Uniqueness Theorem ◽  
Differential Operators ◽  
Mean Value ◽  
Mean Value Theorem ◽  
Initial Value ◽  
First Order ◽  
Fractional Differential ◽  
The Mean ◽  
Fractional Differential Operators ◽  
First Order Differential Equations

AbstractWe generalize the classical mean value theorem of differential calculus by allowing the use of a Caputo-type fractional derivative instead of the commonly used first-order derivative. Similarly, we generalize the classical mean value theorem for integrals by allowing the corresponding fractional integral, viz. the Riemann-Liouville operator, instead of a classical (firstorder) integral. As an application of the former result we then prove a uniqueness theorem for initial value problems involving Caputo-type fractional differential operators. This theorem generalizes the classical Nagumo theorem for first-order differential equations.

Degradation of Butylparaben by Ozonation and UV/TiO2 Processes

2012 ◽  
Vol 488-489 ◽  
pp. 159-163 ◽  
Author(s):  
Li Chin Chuang ◽  
Chin Hsiang Luo ◽  
Ming Chieh Chuang ◽  
Miao Chi Wang
Keyword(s):  
Breast Cancer ◽  
Antimicrobial Agent ◽  
Advanced Oxidation Processes ◽  
Estrogenic Activity ◽  
Reaction Rates ◽  
Alkaline Condition ◽  
Oxidation Processes ◽  
First Order ◽  
First Order Kinetics ◽  
Pseudo First Order

Butylparaben is widely used as a bactericide and as an antimicrobial agent in the formation of personal care products (PCPs). Owing to a certain estrogenic activity, a possible relationship with breast cancer has been proved by many researchers. The removal efficiency of butylparaben in aqueous solutions was studied using advanced oxidation processes (AOPs). These results indicate that the reaction rates for the ozonation of butylparaben in water are higher under the concentration of ozone 5 mg/L in alkaline condition. The original concentration of butylparaben almost degraded within 50, 30, and 20 min at ozone concentrations of 1, 3, and 5 mg/L, respectively at pH 11 runs. The ozonation imposed butylparaben with a time dependence that appeared to follow pseudo first-order kinetics. The original butylparaben was degraded 50 %, 40%, 35%, and 32% within 24 hr at pH 3, 6, 9, and 11 respectively by UV/TiO2 process in the O2-sparged concentration of 30 mg/L. The rate constants are 0.045, 0.043, 0.025, and 0.020 hr-1 at the butylparaben concentrations of 10.30, 20.60, 30.90, and 41.20 μM, respectively.

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