1,202 research outputs found
Investigation of the GATA repetitive DNA sequence of the domestic horse (Equus caballus) of: a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Genetics at Massey University
The variation in copy number and organisation of the simple quadruplet repeat (GATA)n in the genome of most animals has made it a .potential tool for DNA fingerprinting. This study was undertaken to explore this application and to investigate its abundance and organisation in the horse genome.
Using the synthetic oligomer (G ATA)5 end-labelled with 32P as a probe, the copy
number of (GATA)n in genomic DNA from leukocytes of male and female horses was determined, and the extent of its polymorphism investigated on Southern blots of DNA digested with various restriction enzymes. To investigate its organisation, a genomic clone containing (GATA)n was isolated, characterized by restriction mapping and sequenced.
(GATA)n constituted 1% of the horse genome. Like the mouse, there was no quantitative sex variation. Mbo I digestion generated a large number of horse DNA
fragments of various sizes up to 5kb which hybridized to the (G AT A)5 probe. Simpler profiles were produced by digestion with Taq I, Alu I, Hae Ill and Hinf I.
The profiles were highly conserved between individuals and between family
members indicating the (G AT A)5 is unlikely to be informative as a DNA fingerprinting probe.
Some intensely hybridizing DNA fragments appeared to be maternally transmitted. This seems to be a novel observation.
A 3.6kb fragment which hybridized to the (G ATA)5 probe was cloned from horse genomic DNA. It was restriction mapped, the GATA-containing region identified
and sequenced. Only about 150bp contained tandemly repeated GATA motifs in strings of about 3-6 repeats interspersed with (GAT)1-2 regions.
The lack of quantitative sex variation suggests that (GATA)n may not have a role in sex determination in horses. Also, its lack of polymorphism makes it unlikely to be informative as a DNA fingerprinting probe
Driving human motor cortical oscillations leads to behaviorally relevant changes in local GABAA inhibition: a tACS-TMS study
Beta and gamma oscillations are the dominant oscillatory activity in the human motor cortex (M1). However, their physiological basis and precise functional significance remain poorly understood. Here, we used transcranial magnetic stimulation (TMS) to examine the physiological basis and behavioral relevance of driving beta and gamma oscillatory activity in the human M1 using transcranial alternating current stimulation (tACS). tACS was applied using a sham-controlled crossover design at individualized intensity for 20 min and TMS was performed at rest (before, during, and after tACS) and during movement preparation (before and after tACS). We demonstrated that driving gamma frequency oscillations using tACS led to a significant, duration-dependent decrease in local resting-state GABAA inhibition, as quantified by short interval intracortical inhibition. The magnitude of this effect was positively correlated with the magnitude of GABAA decrease during movement preparation, when gamma activity in motor circuitry is known to increase. In addition, gamma tACS-induced change in GABAA inhibition was closely related to performance in a motor learning task such that subjects who demonstrated a greater increase in GABAA inhibition also showed faster short-term learning. The findings presented here contribute to our understanding of the neurophysiological basis of motor rhythms and suggest that tACS may have similar physiological effects to endogenously driven local oscillatory activity. Moreover, the ability to modulate local interneuronal circuits by tACS in a behaviorally relevant manner provides a basis for tACS as a putative therapeutic intervention.SIGNIFICANCE STATEMENT Gamma oscillations have a vital role in motor control. Using a combined tACS-TMS approach, we demonstrate that driving gamma frequency oscillations modulates GABAA inhibition in the human motor cortex. Moreover, there is a clear relationship between the change in magnitude of GABAA inhibition induced by tACS and the magnitude of GABAA inhibition observed during task-related synchronization of oscillations in inhibitory interneuronal circuits, supporting the hypothesis that tACS engages endogenous oscillatory circuits. We also show that an individual's physiological response to tACS is closely related to their ability to learn a motor task. These findings contribute to our understanding of the neurophysiological basis of motor rhythms and their behavioral relevance and offer the possibility of developing tACS as a therapeutic tool
Use of Building Information Modelling Tools for Structural Health Monitoring
The study of Information and Communication Technology applications in construction industry have developed greatly for computer programming and management strategies. As a response to the increasing challenges of construction projects, extensive researches have brought about numerous ICT tools such as Building Information Modelling tools, Lean Construction and Lean Design tools, and Integrated Project Delivery management tools to succour the construction industry. Building Information Modelling in particular is acknowledged in the industrial and academic circles as the new Computer Aided Design paradigm and hence, repositions it as the preferred approach to managing design, construction, maintenance and documentation of building projects. But the use of Building Information Modelling tools for structural health monitoring have not been adequately explored. This study employs Building Information Modelling as a tool for diagnosing and correcting structural design flaws in a building under construction. The design flaws in a complex staircase was identified while more realistic options of the design were quickly created and articulated for a safer outcome of the project. The results obtained highlights the benefits of Building Information Modelling applications such as enhanced safety, improved cost, time savings, quality improvements and better project management and execution
Selective versus non-selective shunts for the prevention of variceal rebleeding
This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:
To assess the benefits and harms of any type of selective shunt versus any type of non-selective shunt for the prevention of oesophagogastric
variceal rebleeding in people with portal hypertension.http://www.cochranelibrary.com2020-11-07am2020Surger
Resin Distribution in Medium Density Fiberboard. Quantification of UF Resin Distribution on Blowline-and Dry-Blended MDF Fiber and Panels
A novel technique has been developed for visualizing urea formaldehyde (UF) resin distribution on fibers and within MDF panels. A fluorescent label was chemically bound to the resin, and digital images of resinated fiber, generated via confocal laser scanning microscopy (CLSM), were analyzed. Results indicate that this technique can be used to quantify UF resin coverage and distribution as well as provide information on resin film thickness on MDF fiber before pressing and in panels. The technique can distinguish between different methods of resination and was employed to determine that these processes can result in different surface coverages of UF resin on MDF fiber. Resin injected at the end of the blowline gave significantly less resin coverage of fiber than that which was injected at the start of the blowline. UF resin droplets were also relatively thicker and less dispersed when injected at the end of the blowline. Visualization of UF resin also illustrated resin distribution changes upon pressing of fiber particularly in the presence of wax. This result has important implications for future studies targeting optimization of resin deposition, since the droplet size distribution, as applied to the fiber, may not correspond to the droplet size distribution of resin in the panel
Riparian Management in Intensive Grazing Systems for Improved Biodiversity and Environmental Quality: Productive Grazing, Healthy Rivers
Within high rainfall intensive grazing systems of southern Victoria, riparian zones are often degraded due to vegetation clearing, stock access and inappropriate farm management. Streams in these landscapes often have poor water quality and reduced biodiversity due to degraded terrestrial and aquatic ecosystems. Improved management of riparian zones depends on developing tools and practices for integration into productive grazing systems. This paper describes the approaches used and the tools developed in the ‘Productive Grazing, Healthy Rivers: Improving riparian and in-stream biodiversity’ project
ASSESSMENT OF STRENGTH PROPERTIES OF CASSAVA PEEL ASH-CONCRETE
Basic conventional building materials like cement and aggregates are becoming increasingly expensive due to high cost incurred in their processes, production and transportation. The utilization of locally available materials such as cassava peel ash that can either reduce or replace the conventional ones is being considered. This
paper investigated the effect of partial replacement of cassava peel ash with ordinary Portland cement at 5, 10, 15, 20 and 25%. The cassava peel ash was obtained by calcinations of cassava peel to 7000 c temperature. Cube samples of size 150 x 150 x 150 were prepared for concrete grade 30 and cured in water for 7, 14, 28, 90, 120
and 180 days after which they were subjected to compressive strength, tensile strength, durability, porosity, water absorption, slump, compact factor and shrinkage tests. The results showed that partial replacement of 10 and 15% gave compressive strength comparable to the control with 0% replacement and optimum replacement is 10%. It was discovered that the cassava peel ash contains all the main chemical constituents of cement though in lower percentage compared with OPC which shows that it can serve as a suitable replacement if the right percentage is used. However, its durability and sulphric acid resistance improved considerably at 10% replacement of cement with cassava peel ash. The study recommends that concrete made with cassava peel ash can be used for light construction works where high strength is not major requirement but where durability is a major concern
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