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Noise Exposure
Noise health effects are the physical and psychological health consequences of regular exposure to consistent elevated sound levels. Noise from traffic, in particular, is considered by the World Health Organization to be one of the worst environmental stressors for humans, second only to air pollution. Elevated workplace or environmental noise can cause hearing impairment, tinnitus, hypertension, ischemic heart disease, annoyance, and sleep disturbance. Changes in the immune system and birth defects have been also attributed to noise exposure. Although age-related health effects (presbycusis) occur naturally with age, in many countries the cumulative impact of noise is sufficient to impair the hearing of a large fraction of the population over the course of a lifetime. Noise exposure has been known to induce noise-induced hearing loss, tinnitus, hypertension, vasoconstriction, and other cardiovascular adverse effects. Chronic noise exposure has been associated with sleep disturban ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tinnitus
Tinnitus is the perception of sound when no corresponding external sound is present. Nearly everyone experiences a faint "normal tinnitus" in a completely quiet room; but it is of concern only if it is bothersome, interferes with normal hearing, or is associated with other problems. While often described as a ringing, it may also sound like a clicking, buzzing, hissing or roaring. It may be soft or loud, low- or high- pitched, and may seem to come from one or both ears or from the head itself. In some people, it may interfere with concentration, and in some cases is associated with anxiety and depression. Tinnitus is usually associated with a degree of hearing loss and decreased comprehension of speech in noisy environments. It is common, affecting about 10–15% of people. Most, however, tolerate it well, and it is a significant problem in only 1–2% of all people. It can trigger a fight-or-flight response, as the brain may perceive it as dangerous and important. The word ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cortisol
Cortisol is a steroid hormone, in the glucocorticoid class of hormones. When used as a medication, it is known as hydrocortisone. It is produced in many animals, mainly by the ''zona fasciculata'' of the adrenal cortex in the adrenal gland. It is produced in other tissues in lower quantities. It is released with a diurnal cycle and its release is increased in response to stress and low blood-glucose concentration. It functions to increase blood sugar through gluconeogenesis, to suppress the immune system, and to aid in the metabolism of fat, protein, and carbohydrates. It also decreases bone formation. Many of these functions are carried out by cortisol binding to glucocorticoid or mineralocorticoid receptors inside the cell, which then bind to DNA to impact gene expression. Health effects Metabolic response Metabolism of glucose In general, cortisol stimulates gluconeogenesis (the synthesis of 'new' glucose from non-carbohydrate sources, which occurs mainly in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myocardial Infarction
A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops to the coronary artery of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which may travel into the shoulder, arm, back, neck or jaw. Often it occurs in the center or left side of the chest and lasts for more than a few minutes. The discomfort may occasionally feel like heartburn. Other symptoms may include shortness of breath, nausea, feeling faint, a cold sweat or feeling tired. About 30% of people have atypical symptoms. Women more often present without chest pain and instead have neck pain, arm pain or feel tired. Among those over 75 years old, about 5% have had an MI with little or no history of symptoms. An MI may cause heart failure, an irregular heartbeat, cardiogenic shock or cardiac arrest. Most MIs occur due to coronary artery disease. Risk factors include high blood pressure, smoking, diabetes, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A-weighting
A-weighting is the most commonly used of a family of curves defined in the International standard IEC 61672:2003 and various national standards relating to the measurement of sound pressure level. A-weighting is applied to instrument-measured sound levels in an effort to account for the relative loudness perceived by the human ear, as the ear is less sensitive to low audio frequencies. It is employed by arithmetically adding a table of values, listed by octave or third-octave bands, to the measured sound pressure levels in dB. The resulting octave band measurements are usually added (logarithmic method) to provide a single A-weighted value describing the sound; the units are written as dB(A). Other weighting sets of values – B, C, D and now Z – are discussed below. The curves were originally defined for use at different average sound levels, but A-weighting, though originally intended only for the measurement of low-level sounds (around 40 phon), is now commonly used for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidative Stress
Oxidative stress reflects an imbalance between the systemic manifestation of reactive oxygen species and a biological system's ability to readily Detoxification, detoxify the reactive intermediates or to repair the resulting damage. Disturbances in the normal redox state of cells can cause toxic effects through the production of peroxides and free radicals that damage all components of the cell, including proteins, lipids, and DNA. Oxidative stress from Cellular respiration, oxidative metabolism causes base damage, as well as DNA damage (naturally occurring), strand breaks in DNA. Base damage is mostly indirect and caused by the reactive oxygen species generated, e.g., O2− (superoxide radical), OH (hydroxyl radical) and H2O2 (hydrogen peroxide). Further, some reactive oxidative species act as cellular messengers in redox signaling. Thus, oxidative stress can cause disruptions in normal mechanisms of cellular signaling. In humans, oxidative stress is thought to be involved in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circulatory System
The blood circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the entire body of a human or other vertebrate. It includes the cardiovascular system, or vascular system, that consists of the heart and blood vessels (from Greek ''kardia'' meaning ''heart'', and from Latin ''vascula'' meaning ''vessels''). The circulatory system has two divisions, a systemic circulation or circuit, and a pulmonary circulation or circuit. Some sources use the terms ''cardiovascular system'' and ''vascular system'' interchangeably with the ''circulatory system''. The network of blood vessels are the great vessels of the heart including large elastic arteries, and large veins; other arteries, smaller arterioles, capillaries that join with venules (small veins), and other veins. The Closed circulatory system, circulatory system is closed in vertebrates, which means that the blood never leaves the network of blood vessels. Some in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tinnitus
Tinnitus is the perception of sound when no corresponding external sound is present. Nearly everyone experiences a faint "normal tinnitus" in a completely quiet room; but it is of concern only if it is bothersome, interferes with normal hearing, or is associated with other problems. While often described as a ringing, it may also sound like a clicking, buzzing, hissing or roaring. It may be soft or loud, low- or high- pitched, and may seem to come from one or both ears or from the head itself. In some people, it may interfere with concentration, and in some cases is associated with anxiety and depression. Tinnitus is usually associated with a degree of hearing loss and decreased comprehension of speech in noisy environments. It is common, affecting about 10–15% of people. Most, however, tolerate it well, and it is a significant problem in only 1–2% of all people. It can trigger a fight-or-flight response, as the brain may perceive it as dangerous and important. The word ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unilateral Hearing Loss
Unilateral hearing loss (UHL) is a type of hearing impairment where there is normal hearing in one ear and impaired hearing in the other ear. Signs and symptoms Patients with unilateral hearing loss have difficulty: * Hearing conversation on their impaired side * Localizing sound * Understanding speech in the presence of background noise * In interpersonal interaction in social settings * Focusing on individual sound sources in large, open environments * Heavy impairment of the auditory Figure–ground perception In quiet conditions, speech discrimination is no worse than normal hearing in those with partial deafness; however, in noisy environments speech discrimination is almost always severe. The prevalence is 3–8.3% of the population. Individuals who are diagnosed with Single Sided Deafness have difficulties with sound localization and speech in noise discrimination. Children with SSD are more likely to experience developmental delays- school, speech, behavioral problems. C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loud Music
Loud music is music that is played at a high volume, often to the point where it disturbs others and causes hearing damage. It may include music that is sung live, played with musical instruments, or with electronic media, such as Radio broadcasting, CD, or MP3 players. Playing loud music that can be heard from outside of the property from where it is being played is considered to be rude by many societies. Among those opposed to the practice, it may result in the loss of respect and possible legal action. In certain contained settings, such as nightclubs or concerts, music is often played very loudly, but is viewed as acceptable. Overview Criminal and civil Disturbing the peace by playing loud music in the night is a criminal offense, typically a misdemeanor. The exact definition of what constitutes a loud music violation varies by location, either at a certain volume (measured in decibels) or the distance from the source at which the music can be heard. The time of day is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Work Accident
A work accident, workplace accident, occupational accident, or accident at work is a "discrete occurrence in the course of work" leading to physical or mental occupational injury. According to the International Labour Organization (ILO), more than 337 million accidents happen on the job each year, resulting, together with occupational diseases, in more than 2.3 million deaths annually. The phrase "in the course of work" can include work-related accidents happening off the company's premises, and can include accidents caused by third parties, according to Eurostat. The definition of work accident includes accidents occurring "while engaged in an economic activity, or at work, or carrying on the business of the employer" according to the ILO. The phrase "physical or mental harm" means any injury, disease, or death. Occupational accidents differ from occupational diseases as accidents are unexpected and unplanned occurrences (e.g., mine collapse), while occupational diseases are "c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of California, Berkeley
The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a public land-grant research university in Berkeley, California. Established in 1868 as the University of California, it is the state's first land-grant university and the founding campus of the University of California system. Its fourteen colleges and schools offer over 350 degree programs and enroll some 31,800 undergraduate and 13,200 graduate students. Berkeley ranks among the world's top universities. A founding member of the Association of American Universities, Berkeley hosts many leading research institutes dedicated to science, engineering, and mathematics. The university founded and maintains close relationships with three national laboratories at Berkeley, Livermore and Los Alamos, and has played a prominent role in many scientific advances, from the Manhattan Project and the discovery of 16 chemical elements to breakthroughs in computer science and genomics. Berkeley is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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