Detection of artefacts in sleep studies data Literature review

Detection of artefacts in sleep studies data - Literature review Example The studies have yielded different findings and this implies that scientists are yet to comprehend the phenomenon fully. However, empirical studies have established that sleep is important for enhancing normal and healthy performance of physical and mental aspects of the human body. In addition to these findings, sleeping process has been exclusively studied to establish the various stages involved and the brains level of activity during the process. This paper investigates the various stages of sleep and the role of sleep to human beings. Recent scientific studies have discredited the common misconception that regarded sleep as a dormant mental state. Scientists have established that the brain maintains a high level of activity during sleep. In addition, sleep influences the physical and mental functioning of our bodies in various ways that continue to attract numerous studies in order to enhance our understanding about the phenomenon (Baddely, 2000). Nerve-triggering chemicals call ed neurotransmitters determine whether we are awake or sleep by stimulating various groups of nerve cells and neurons in the brain. In the brainstem that links the brain with the spinal cord, neurons produce various neurotransmitters such as norepinephrine and serotonin that ensures that some parts of the brain remain active while in a wakeful state. When we begin falling asleep, neurons at the base of the brain start signalling and they suppress the neurotransmitters that keep us awake (Espana and Scammel, 2011). According to Espana and Scammel (2011), the state of wakefulness is enhanced by neurons present in the midbrain, pons, and in the posterior hypothalamus that produce various types of neurotransmitters, including histamine, serotonin, dopamine, acetylcholine, orexin and norepinephrine. The neurotransmitters that determine wakefulness and sleep diffuse actively in the brain, activating the targeted regions of in the cortex and forebrain. The reciprocal inhibition that occurs between sleep and wake controlling regions in the brain helps in the production of sleep and wakefulness with quick transitions between the states (Espana and Scammel, 2011, p 847). Scientists use three basic measures to classify sleep into different stages. The three measures include the gross brain activity, muscle tone and the eye movement (Carlson, 2001). Electroencephalograph (EEG) machine detects gross brain wave activity from which it produces summary of electrical action from the brain. The muscle tone is measured using an electromyogram (EMG) machine while eye movements during sleep are recorded using electro- oculogram (EOG). According to Harvey and Bruce (2006), electroencephalograph (EEG) is the most widely applied measure of distinguishing the different sleep stages while electromyogram (EMG) and electro-encephalograph are crucial in differentiating rapid eye movement (REM) sleep from the other types. Two different states alternate in cycles when a person is asleep and they portray the varying levels of neural activity in the brain. The states that constitute sleep are non-rapid eye movement (NREM) and rapid eye movement (REM) (Zhang, 2004). According to Zhang (2004), each of these states is associated with a unique and different form of brain wave activity. Non -rapid eye movement (NREM) is subdivided into four different stages that include stage 1, 2, 3 and 4. Therefore, typical sleep is made up of five stages, where NREM constitute 75% and the rest is REM (Carlson, 2001). The stages of REM sleep and NREM

Moving Away from Traditional Transaction-Based Financial Information Essay

Moving Away from Traditional Transaction-Based Financial Information to Technologically Based Non-Financial Information - Essay Example Many businesses have in the recent times shifted their focus from using the traditional transaction-based financial information towards using technologically based non-financial information (Agresti, 2002). This has been largely due to the fact that the traditional approaches usually limit themselves through the definition of their cost behaviors in the terms of their production along with sales level (Burns and Baldvinsdottir, 2007). The traditional methods were mostly utilized for the purposes of giving reports when the valuations of the items in their income statements and balance sheets (Zhou, 2012). The method also had so many restrictions as the statements prepared were supposed to comply with the GAAP principles. As a result of being outdated in their practices the governing body of the management discipline brought more technological advances that would have helped in resolving the issue (Cooper, 2009). Additionally, in the recent past there has been a great shift by the mana gements of businesses across the globe towards the use of technologically based non-financial pieces of information (Burns and Baldvinsdottir, 2007). ... These two types of change within the management field are evident simultaneously across many businesses along with organizations (Burns and Baldvinsdottir, 2007). Reports indicate that such an occurrence might occur because both of these changes may be subjected to the same types of normative pressures though they are basically mutually independent (Agresti, 2002). The management accounting profession has in the modern world changed their views on various aspects that affect their operations. For instance, less emphasis has recently been placed on the acquisition of technical knowledge along with the traditional skills of doing business (Burns and Baldvinsdottir, 2007). The new work of the management accountant thus relies on his ability of interpreting non-financial information for the benefit of a business entity or organization (O’Sullivan, 2010). This has made the management accountants new work to be described as involving the offering of consultancy services to the inter nal operations of a business. Change within the management profession has also been driven by the fact that the accountants are currently being involved in the support of decisions and offering of professional advice to the organization (Agresti, 2002). The advice provided is on the strategic along with operational issues of an organization and the application of special technical skills for the benefit of the organization (Cooper, 2009). The issue of leadership is directly related to the management profession and this implies that the methods applied by the professionals in the field have to change. The change should therefore be aimed at providing an increase in the collaborations beyond the financing option and working in teams that have multiple purposes in a