Water stress

Examples of Water stress in the following topics:

• Water’s Cohesive and Adhesive Properties

  • Cohesion allows substances to withstand rupture when placed under stress while adhesion is the attraction between water and other molecules.
  • Cohesion allows for the development of surface tension, the capacity of a substance to withstand being ruptured when placed under tension or stress.
  • Adhesion is observed when water "climbs" up the tube placed in a glass of water: notice that the water appears to be higher on the sides of the tube than in the middle.
  • In another example, insects such as the water strider use the surface tension of water to stay afloat on the surface layer of water and even mate there.
  • Water's cohesive and adhesive properties allow this water strider (Gerris sp.) to stay afloat.

• River Valley Civilizations

  • A hydraulic empire (also known as hydraulic despotism, or water monopoly empire) is a social or governmental structure which maintains power through exclusive control over water access.
  • Access to water is still crucial to modern civilizations; water scarcity affects more than 2.8 billion people globally.
  • Water stress is the term used to describe difficulty in finding fresh water or the depletion of available water sources.
  • Water shortage is the term used when water is less available due to climate change, pollution, or overuse.
  • Water crisis is the term used when there is not enough fresh, clean water to meet local demand.

• Hormonal Regulation of Stress

  • Some stresses, such as illness or injury, can last for a long time.
  • The glucocorticoids mobilize lipid and protein reserves, stimulate gluconeogenesis, conserve glucose for use by neural tissue, and stimulate the conservation of salts and water.
  • Long-term stress response differs from short-term stress response.
  • Mineralocorticoids function to regulate ion and water balance of the body.
  • The hormone aldosterone stimulates the reabsorption of water and sodium ions in the kidney, which results in increased blood pressure and volume.

• Water Waves

  • Examples of water waves can be found in the sea, a lake or a bath tub.
  • If you blow on the surface of any body of water with enough force you can generate water waves.
  • Both air pressure differences between the upwind and the lee side of a wave crest, as well as friction on the water surface by the wind (making the water to go into the shear stress), contribute to the growth of the waves.
  • Deep water corresponds with a water depth larger than half the wavelength, as is a common case in the sea and ocean.
  • The deep-water group velocity is half the phase velocity.

• Bacterial Differentiation

  • However, this consistency could be affected in some circumstances (such as environmental stress) and changes in bacterial shape and size.
  • For instance, rod shapes may allow bacteria to attach more readily in environments with shear stress (e.g., in flowing water).
  • Oxidative stress, nutrient limitation, DNA damage and antibiotics exposure are some stress conditions to which bacteria respond, altering their DNA replication and cell division.
  • Filamentous bacteria have been considered to be over-stressed, sick and dying members of the population.
  • Nutritional stress can change bacterial morphology.

• Hormonal Regulation of the Excretory System

  • The concentration of electrolytes in the blood rises when there is water loss caused by excessive perspiration, inadequate water intake, or low blood volume due to blood loss.
  • Dehydration or physiological stress can cause an increase of osmolarity above threshold levels, which, in turn, raises ADH secretion and water retention, causing an increase in blood pressure.
  • ADH travels in the bloodstream to the kidneys where it changes the kidneys to become more permeable to water by temporarily inserting water channels, aquaporins, into the kidney tubules.
  • In contrast to ADH, which promotes the reabsorption of water to maintain proper water balance, aldosterone maintains proper water balance by enhancing Na+ reabsorption and K+ secretion from extracellular fluid of the cells in kidney tubules.
  • This increases water retention and blood pressure.

• Thermal Stresses

  • Thermal stress is created by thermal expansion or contraction.
  • Thermal stress can be destructive, such as when expanding gasoline ruptures a tank.
  • Forces and pressures created by thermal stress can be quite large.
  • A significant portion of the rise in sea level that is resulting from global warming is due to the thermal expansion of sea water.
  • Another example of thermal stress is found in the mouth.

• Managing Stress Through Conventional and Alternative Medicine

  • Stress management resources aim to control or diminish a person's level of stress through both conventional and alternative methods.
  • Stress management resources aim to control a person's level of stress, whether chronic and recurring or acute and unique.
  • Stress management techniques provide a way to cope with stress and its symptoms to promote and maintain general well-being.
  • This finding led to the belief that stress was somehow outside of or beyond the control of the person experiencing stress.
  • This precept allows stress to be controlled by the person and provides the basis for most stress management techniques.

• Effect of a Common Ion on Solubility

  • This is because Le Chatelier's principle states the reaction will shift toward the left (toward the reactants) to relieve the stress of the excess product.
  • Scientists take advantage of this property when purifying water.
  • In areas where water sources are high in chalk or limestone, drinking water contains excess calcium carbonate CaCO3.
  • In the water treatment process, sodium carbonate salt is added to precipitate the calcium carbonate.
  • If we go back and compare, only 4.7 percent as much CaF2 will dissolve in 0.10 M CaCl2 as in pure water:

• How Stress Impacts our Health

  • Stress is a necessity for life and is a primary biological incentive for all.
  • Acute stress occurs in the short-term and is usually resolved rather quickly; chronic stress is long-term and usually unresolved, leading to a variety of problems.
  • Many people experience some type of depressive mood or feeling in relation to stress, and excessive amounts of stress has been shown to contribute to depression or anxiety.
  • One of the most serious ways that stress can impact psychological well-being is in post-traumatic stress disorder (PTSD).
  • Cortisol, also known as the "stress hormone", plays an integral role in our body's reaction to stress.