33 research outputs found
Effect of changes in pipe direction across surcharged manholes on dispersion and head loss.
From the water quality perspective, looking at a sewer system as a reactor whose
effluent should be regulated in terms of water quality, solute tracer studies need to be
undertaken to define the retention and spread of temporally varying concentrations.
Focussing on a manhole, its aspects such as shape, ratio of pipe and manhole diameter,
and pipe direction all affect the transport of the solute through the sewer system.
The aim of this study is to quantify the magnitude and changes in dispersive fraction (y)
used in the ADZ technique, and head loss coefficient (K) due to changes in pipe
direction across a manhole. Under surcharge conditions, solute transport along plane
angles such as 0°, 30°, 60° and 90°, of an inlet and an outlet pipes with/without
benching was investigated for a range of surcharge and discharge. Additionally, the
head losses due to such an angle were also measured. From data analysis, both the
dispersive fraction and the head loss coefficient were properties of each plane angle. For
example, at the angle of 300 -unbenched, the dispersive fraction was constant at
approximately 0.7 and the head loss coefficient was constant at about 2.22.
Moreover, these comprehensive processed data were beneficial to basic knowledge of
solute mixing. First, the square root of the ratio of head loss and residence time,
represented by energy dissipation, was found to be linear to flow rate. Hence, it might
be used as a conversion of a head loss to residence time. Second, two cell ADZ
technique was developed to enhance the travel time prediction of a downstream
concentration profile. The two cell technique was able to predict the concentration
profile very well, but due to difficulty in application, a single cell ADZ technique was
more useful in general
Acute effects of barakol and serotonergic drugs on exploratory behaviour in rats
Barakol (10 mg/kg, i.p.), an active ingredient extracted from Cassia siamea, has been shown to have anxiolytic properties on the elevated plus-maze at a low dose similar to diazepam and to increase exploratory and locomotor behaviour. Drugs increasing serotonergic function also alter exploratory activity. The mechanism underlying the effects of barakol on exploratory behaviour has not been studied, therefore, the aim of the present study was to investigate exploratory activity in rats treated with barakol compared with drugs known to have specific action on the 5HT system. Exploratory behaviours were monitored in the rat using the holeboard model. The results show that the 5HT1A receptor agonist 8-OH-DPAT (1 mg/kg, i.p.) significantly (
Long-term exposure to sensory feed additives during the gestational and postnatal periods impacts sows’ colostrum and milk sensory profiles, piglets’ growth and feed intake
This study investigated the effect of feed supplementation in sows and/or their progeny with two sensory feed additives (FA1: limonene and cinnamaldehyde; FA2: menthol, carvone and anethole) on sows’ feed intake, body weight, fat deposition, and colostrum/milk composition, as well as piglets’ feed intake growth and feed efficiency from birth to slaughter at postnatal day 160 (PND160). During the last third of gestation and the whole of lactation, sows were subjected to a control diet (C) or the same diet containing FA1 or FA2 at 0.1% of complete feed content. Colostrum/milk samples were taken at day 1, 14, and 28 of lactation for gas chromatography-mass spectrometry (GC-MS) analyses. After weaning, the progeny was subjected to a control diet (C) or experimental diets with a sweetener (0.015%) but no other additive (S), or to diets with a sweetener and the additive FA1 (FA1S) or FA2 (FA2S). There was no effect of dietary treatment on sows’ feed intake, body weight, or adiposity (P > 0.15 for all), but the sensory characteristics of their colostrum/milk were modified by the diet and diet*time interaction. Limonene concentrations were higher in FA1 samples from PND1 to PND28, whereas carvone and anethole concentrations were higher in FA2 samples from PND1 to PND28. The concentration of these three compounds increased with time in the respective groups where they were mostly detected. Menthol concentrations were higher in FA2 samples at PND14 and PND28, but there was no time effect. Overall, cinnamaldehyde was always below the detection range. Piglets born from FA1 and FA2 sows had higher body weight (P = 0.034 at PND160), average daily gain (ADG P = 0.036 for PND0-160), and average daily feed intake (ADFI P = 0.006 for PND28-160) than piglets born from C sows. Overall, piglets that were never exposed to FA or only after weaning had lower ADG (P = 0.030 for PND0-160) and ADFI (P = 0.016 for PND28-160) than piglets that were exposed to FA only via the maternal diet, the condition combining both pre- and post-natal exposure being intermediary. In conclusion, FA1 and FA2 provided to gestating and lactating sows increased the progeny’s feed intake and growth, suggesting nutritional programming and/or sensory conditioning during the perinatal period. Addition of FA only in the progeny’s diet was not beneficial
Citrus aurantium L. essential oil exhibits anxiolytic-like activity mediated by 5-HT1A-receptors and reduces cholesterol after repeated oral treatment
Mechanisms underlying the antidepressant properties of St. John's wort (Hypericum perforatum)
EThOS - Electronic Theses Online ServiceGBUnited Kingdo
S HORT RE P ORT Comparison between ECL and ELISA for the detection of salivary cortisol and determination of the relationship between cortisol in saliva and serum measured by ECL
ABSTRACT: Salivary cortisol has been increasingly used as a stress biomarker since saliva sampling induces less additional stress than blood sampling. Enzyme-linked immunosorbent assay (ELISA) has been commonly used to measure salivary cortisol in stress related research. Recently, electrochemiluminescence (ECL), a routine immunoassay analyser, has been suggested to measure salivary cortisol. Therefore, the aims of this study are: (1) to compare salivary cortisol level measured by ELISA and ECL and (2) to determine the relationship between salivary cortisol and serum cortisol measured by ECL. Both salivary and serum samples were collected from 83 volunteers for cortisol measurement by ECL analysis. The salivary cortisol value was 3% of that of the serum cortisol. For ECL, the positive correlation between salivary and serum cortisol levels was significant (r = 0.84; p < 0.001). The measurement by two different methods did not show any significant difference (p = 0.5497). The correlation of salivary cortisol values measured by both techniques was significant (r = 0.81; p < 0.001). The result suggests that ECL seems to be more practical and cheaper for salivary cortisol measurement
Anxiety-like behaviour and <i>c-fos</i> expression in rats that inhaled vetiver essential oil
<div><p>Vetiver essential oil (VEO) has been used in aromatherapy for relaxation. This study aimed to investigate the effects of VEO on an anxiety-related behavioural model (the elevated plus-maze, EPM) and immediate-early gene <i>c-fos</i> in amygdala, known to be involved in anxiety. Male Wistar rats were administered diazepam (1 mg/kg i.p.) for 30 min or inhalated with VEO (1%, 2.5% or 5% w/w) for 7 min prior to exposure to the EPM. Then, the effects of 2.5% VEO, the anxiolytic dose, on c-<i>fos</i> expression in amygdala were investigated. The rats given either 2.5% VEO or diazepam exhibited an anxiolytic-like profile in the EPM. VEO and diazepam significantly increased <i>c-fos</i> expression in the lateral division of the central amygdaloid nucleus (CeL). Therefore, the anxiolytic properties of VEO might be associated with altering neuronal activation in CeL. However, future studies are needed to investigate the precise mechanism of action of VEO.</p></div
End-point rapid detection of total and pathogenic Vibrio parahaemolyticus (tdh+ and/or trh1+ and/or trh2+) in raw seafood using a colorimetric loop-mediated isothermal amplification-xylenol orange technique
Background Vibrio parahaemolyticus is the leading cause of bacterial seafood-borne gastroenteritis in humans worldwide. To ensure seafood safety and to minimize the occurrence of seafood-borne diseases, early detection of total V. parahaemolyticus (pathogenic and non-pathogenic strains) and pathogenic V. parahaemolyticus (tdh+ and/or trh1+ and/or trh2+) is required. This study further improved a loop-mediated isothermal amplification (LAMP) assay using xylenol orange (XO), a pH sensitive dye, to transform conventional LAMP into a one-step colorimetric assay giving visible results to the naked eye. LAMP-XO targeted rpoD for species specificity and tdh, trh1, and trh2 for pathogenic strains. Multiple hybrid inner primers (MHP) of LAMP primers for rpoD detection to complement the main primer set previously reported were designed by our group to maximize sensitivity and speed. Methods Following the standard LAMP protocol, LAMP reaction temperature for rpoD, tdh, trh1, and trh2 detection was first determined using a turbidimeter. The acquired optimal temperature was subjected to optimize six parameters including dNTP mix, betaine, MgSO4, Bst 2.0 WarmStart DNA polymerase, reaction time and XO dye. The last parameter was done using a heat block. The color change of the LAMP-XO result from purple (negative) to yellow (positive) was monitored visually. The detection limits (DLs) of LAMP-XO using a 10-fold serial dilution of gDNA and spiked seafood samples were determined and compared with standard LAMP, PCR, and quantitative PCR (qPCR) assays. Subsequently, the LAMP-XO assay was validated with 102 raw seafood samples and the results were compared with PCR and qPCR assays. Results Under optimal conditions (65 °C for 75 min), rpoD-LAMP-XO and tdh-LAMP-XO showed detection sensitivity at 102 copies of gDNA/reaction, or 10 folds greater than trh1-LAMP-XO and trh2-LAMP-XO. This level of sensitivity was similar to that of standard LAMP, comparable to that of the gold standard qPCR, and 10-100 times higher than that of PCR. In spiked samples, rpoD-LAMP-XO, tdh-LAMP-XO, and trh2-LAMP-XO could detect V. parahaemolyticus at 1 CFU/2.5 g spiked shrimp. Of 102 seafood samples, LAMP-XO was significantly more sensitive than PCR (P < 0.05) for tdh and trh2 detection and not significantly different from qPCR for all genes determined. The reliability of tdh-LAMP-XO and trh2-LAMP-XO to detect pathogenic V. parahaemolyticus was at 94.4% and 100%, respectively. Conclusions To detect total and pathogenic V. parahaemolyticus, at least rpoD-LAMP-XO and trh2-LAMP-XO should be used, as both showed 100% sensitivity, specificity, and accuracy. With short turnaround time, ease, and reliability, LAMP-XO serves as a better alternative to PCR and qPCR for routine detection of V. parahaemolyticus in seafood. The concept of using a one-step LAMP-XO and MHP-LAMP to enhance efficiency of diagnostic performance of LAMP-based assays can be generally applied for detecting any gene of interest