801 research outputs found
Protective role of aqueous extract of Hibiscus sabdariffa (calyx) against potassium bromate induced tissue damage in wistar rats
The protective role of aqueous extract of Hibiscus sabdariffa (calyx) against potassium bromate induced tissue damage was investigated in rat tissues (brain, kidney, stomach, spleen, heart and liver). The rats were divided into four groups. Group A was administered with 0.25 M sucrose only (base line control), Group B with 60 mg/kg body weight of potassium bromate, and Group C with 250 mg/kg body weight of extracts. Group D was administered 500 mg/kg body weight of extract. Group A and B were used as control groups, while Group C and D were the experimentals. The oral administration of potassium bromate to groups B, C and D were done eight hours before sacrifice. Lipid peroxidation was monitored by colorimetric determination of amino acid, protein and malondialdehyde level in the tissues. The organ-to-body weight ratio was taken as indication for inflammation and necrosis of the tissues investigated. The results of the test groups were statistically (p < 0.05) compared with the base linecontrol and the group B. There was no significant difference in the organ-to-body weight ratio in all the tissues investigated at both doses, when compared with base line control, but showed a significant decrease when compared with group B. The protein level of the tissues investigated showed a similar trend but the stomach shows significant increase in the protein level. This may be due to accumulation of the toxicant inducing protein synthesis. Amino acid level decreased significantly when comparedwith the base-line control and group B. This may be due to the extract ability to reduce proteolysis. Malondialdehyde level in the test groups decreased significantly in a dose dependent manner in all tissues investigated
Investigations On The Carrier Rate Of Pasteurella Multocida In Black Rats (Rattus Rattus) In A Commercial Quail Farm
The aim was to investigate the level of Pasteurella Multocida infection from two anatomic sites of black rats (Rattus Rattus), popularly referred to as house or roof rats in a commercial quail farmhouse with recurrent fowl cholera outbreaks and also to evaluate the association between the Pasteurella Multocida found in rats co-habiting quail poultry houses and isolates from outbreaks of fowl cholera. Thus 100 pharyngeal and 100 rectum swabs samples taken from rats co-habiting farmhouse were obtained and evaluated bacteriologically for isolation of P. multocida; 54% of pharyngeal swabs and 62% of rectum swabs were positive for P. multocida. Extended phenotypic characterization of the isolates confirmed the presence of subspecies P. multocida multocida. Subspecies Pasteurella Multocida septica and gallicida were not encountered. Ramdom serotyping of 5 isolates each from the two sites confirmed serotypes A:4. Fowl cholera outbreaks were confirmed on the quail houses and carrier rats had the same Pasteurella Multocida subspecies and serotype as the infected quail. The public health significance of the finding is also discussed.African Journal of Clinical and Experimental Microbiology Vol. 10 (1) 2009: pp. 2-
Sex differences in mathematics and reading achievement are inversely related: within- and across-nation assessment of 10 years of PISA data
We analyzed one decade of data collected by the Programme for International Student Assessment (PISA), including the mathematics and reading performance of nearly 1.5 million 15 year olds in 75 countries. Across nations, boys scored higher than girls in mathematics, but lower than girls in reading. The sex difference in reading was three times as large as in mathematics. There was considerable variation in the extent of the sex differences between nations. There are countries without a sex difference in mathematics performance, and in some countries girls scored higher than boys. Boys scored lower in reading in all nations in all four PISA assessments (2000, 2003, 2006, 2009). Contrary to several previous studies, we found no evidence that the sex differences were related to nations’ gender equality indicators. Further, paradoxically, sex differences in mathematics were consistently and strongly inversely correlated with sex differences in reading: Countries with a smaller sex difference in mathematics had a larger sex difference in reading and vice versa. We demonstrate that this was not merely a between-nation, but also a within-nation effect. This effect is related to relative changes in these sex differences across the performance continuum: We did not find a sex difference in mathematics among the lowest performing students, but this is where the sex difference in reading was largest. In contrast, the sex difference in mathematics was largest among the higher performing students, and this is where the sex difference in reading was smallest. The implication is that if policy makers decide that changes in these sex differences are desired, different approaches will be needed to achieve this for reading and mathematics. Interventions that focus on high-achieving girls in mathematics and on low achieving boys in reading are likely to yield the strongest educational benefits
Recommended from our members
Output from VIP cells of the mammalian central clock regulates daily physiological rhythms
The suprachiasmatic nucleus (SCN) circadian clock is critical for optimising daily cycles in mammalian physiology and behaviour. The roles of the various SCN cell types in communicating timing information to downstream physiological systems remain incompletely understood, however. In particular, while vasoactive intestinal polypeptide (VIP) signalling is essential for SCN function and whole animal circadian rhythmicity, the specific contributions of VIP cell output to physiological control remains uncertain. Here we reveal a key role for SCN VIP cells in central clock output. Using multielectrode recording and optogenetic manipulations, we show that VIP neurons provide coordinated daily waves of GABAergic input to target cells across the paraventricular hypothalamus and ventral thalamus, supressing their activity during the mid to late day. Using chemogenetic manipulation, we further demonstrate specific roles for this circuitry in the daily control of heart rate and corticosterone secretion, collectively establishing SCN VIP cells as influential regulators of physiological timing
Searching for Exoplanets Using a Microresonator Astrocomb
Detection of weak radial velocity shifts of host stars induced by orbiting
planets is an important technique for discovering and characterizing planets
beyond our solar system. Optical frequency combs enable calibration of stellar
radial velocity shifts at levels required for detection of Earth analogs. A new
chip-based device, the Kerr soliton microcomb, has properties ideal for
ubiquitous application outside the lab and even in future space-borne
instruments. Moreover, microcomb spectra are ideally suited for astronomical
spectrograph calibration and eliminate filtering steps required by conventional
mode-locked-laser frequency combs. Here, for the calibration of astronomical
spectrographs, we demonstrate an atomic/molecular line-referenced,
near-infrared soliton microcomb. Efforts to search for the known exoplanet HD
187123b were conducted at the Keck-II telescope as a first in-the-field
demonstration of microcombs
Mindfulness-based interventions for young offenders: a scoping review
Youth offending is a problem worldwide. Young people in the criminal justice system have frequently experienced adverse childhood circumstances, mental health problems, difficulties regulating emotions and poor quality of life. Mindfulness-based interventions can help people manage problems resulting from these experiences, but their usefulness for youth offending populations is not clear. This review evaluated existing evidence for mindfulness-based interventions among such populations. To be included, each study used an intervention with at least one of the three core components of mindfulness-based stress reduction (breath awareness, body awareness, mindful movement) that was delivered to young people in prison or community rehabilitation programs. No restrictions were placed on methods used. Thirteen studies were included: three randomized controlled trials, one controlled trial, three pre-post study designs, three mixed-methods approaches and three qualitative studies. Pooled numbers (n = 842) comprised 99% males aged between 14 and 23. Interventions varied so it was not possible to identify an optimal approach in terms of content, dose or intensity. Studies found some improvement in various measures of mental health, self-regulation, problematic behaviour, substance use, quality of life and criminal propensity. In those studies measuring mindfulness, changes did not reach statistical significance. Qualitative studies reported participants feeling less stressed, better able to concentrate, manage emotions and behaviour, improved social skills and that the interventions were acceptable. Generally low study quality limits the generalizability of these findings. Greater clarity on intervention components and robust mixed-methods evaluation would improve clarity of reporting and better guide future youth offending prevention programs
Event-related alpha suppression in response to facial motion
This article has been made available through the Brunel Open Access Publishing Fund.While biological motion refers to both face and body movements, little is known about the visual perception of facial motion. We therefore examined alpha wave suppression as a reduction in power is thought to reflect visual activity, in addition to attentional reorienting and memory processes. Nineteen neurologically healthy adults were tested on their ability to discriminate between successive facial motion captures. These animations exhibited both rigid and non-rigid facial motion, as well as speech expressions. The structural and surface appearance of these facial animations did not differ, thus participants decisions were based solely on differences in facial movements. Upright, orientation-inverted and luminance-inverted facial stimuli were compared. At occipital and parieto-occipital regions, upright facial motion evoked a transient increase in alpha which was then followed by a significant reduction. This finding is discussed in terms of neural efficiency, gating mechanisms and neural synchronization. Moreover, there was no difference in the amount of alpha suppression evoked by each facial stimulus at occipital regions, suggesting early visual processing remains unaffected by manipulation paradigms. However, upright facial motion evoked greater suppression at parieto-occipital sites, and did so in the shortest latency. Increased activity within this region may reflect higher attentional reorienting to natural facial motion but also involvement of areas associated with the visual control of body effectors. © 2014 Girges et al
Differences in smoking associated DNA methylation patterns in South Asians and Europeans
This is a freely-available open access publication. Please cite the published version which is available via the DOI link in this record.Background
DNA methylation is strongly associated with smoking status at multiple sites across the genome. Studies have largely been restricted to European origin individuals yet the greatest increase in smoking is occurring in low income countries, such as the Indian subcontinent. We determined whether there are differences between South Asians and Europeans in smoking related loci, and if a smoking score, combining all smoking related DNA methylation scores, could differentiate smokers from non-smokers.
Results
Illumina HM450k BeadChip arrays were performed on 192 samples from the Southall And Brent REvisited (SABRE) cohort. Differential methylation in smokers was identified in 29 individual CpG sites at 18 unique loci. Interaction between smoking status and ethnic group was identified at the AHRR locus. Ethnic differences in DNA methylation were identified in non-smokers at two further loci, 6p21.33 and GNG12. With the exception of GFI1 and MYO1G these differences were largely unaffected by adjustment for cell composition. A smoking score based on methylation profile was constructed. Current smokers were identified with 100% sensitivity and 97% specificity in Europeans and with 80% sensitivity and 95% specificity in South Asians.
Conclusions
Differences in ethnic groups were identified in both single CpG sites and combined smoking score. The smoking score is a valuable tool for identification of true current smoking behaviour. Explanations for ethnic differences in DNA methylation in association with smoking may provide valuable clues to disease pathways.Wellcome Trust Enhancement grantMedical Research CouncilDiabetes UKthe British Heart Foundatio
Closure, observation and coupling: on narrative and autopoiesis
An examination of how narrative fiction can be thought of as a form of Autopoiesis (self-organizing system), drawing on Aristotle, Czech structuralism and Niklas Luhmann's systems theory
- …