Stress reducers

Deposition of nickel at rates up to 1 mm/h in the concentrated solution is described by Kendrick . If pure nickel anodes are operated at a current density between 0-5 and 1-OA/dm in suiphamate solutions, a substance which behaves as a stress reducer is produced continuously in sufficient quantity that the stress in deposits can be varied at will from compressive to tensile by adjusting cathode current density and solution temperature. This finding is exploited with the concentrated suiphamate solution in the Ni-Speed processand in a further development cobalt is added to give deposits of... 

To be successful, molded optical elements of plastics must be produced with careful control of the fabricating process. In the case of these optical products it is particularly important that the molding conditions be carefully controlled to minimize molded-in stress. In addition to these stresses reducing the dimensional stability of the products leading to distorted images, the stresses themselves affect the quality of the image. This is a result of the fact that the stresses/strained areas have a different refractive index from that of the... 

The first chapter defines the spatial and functional features of the rhizosphere, which make this environment the primary site of interaction between soil, plant, and microorganisms. Among the multitude of organic compounds present in the rhizosphere tho.se released by plant roots are the most important from a qualitative and quantitative point of view furthermore, the relationships with soil components of any released compound need to be considered (Chapter 2). The release of these compounds strongly depends on the physiological status of the plants and is related to the ability of plant roots to modify the rhizosphere in order to cope with unfavorable stress-reducing conditions. These aspects are dis-... 

The protective antiprotease -antitrypsin (AAT) inhibits several protease enzymes, including neutrophil elastase. In the presence of unopposed AAT activity, elastase attacks elastin, which is a major component of alveolar walls. A hereditary deficiency of AAT results in an increased risk for premature development of emphysema. In the inherited disease, there is an absolute deficiency of AAT. In emphysema resulting from cigarettesmoking, the imbalance is associated with increased protease activity or reduced activity of antiproteases. Activated inflammatory cells release several other proteases, including cathepsins and metalloproteinases. In addition, oxidative stress reduces antiprotease (or protective) activity. 

In summary, oxidant stress reduced water use and photosynthesis, increased leaf drop and fruit drop, and resulted in a severe reduction in yield of marketable fruit. All these effects occurred without the development of plainly visible leaf symptoms. 

When subjected to drought stress, excised wheat Triticum aestivum L.) leaves increase ethylene production as a result of an increased synthesis of ACC 71 and an increased activity of the ethylene-forming enzyme (EFE) which catalyzes the conversion of ACC 71 to ethylene. Rehydratation to relieve water stress reduces EFE activity to levels similar to those in non-stressed tissue. Pretreatment of the leaves with N-benzyladenine (BA) 75 or indole-3-acetic acid lAA 76 prior to drought stress caused further increase in ethylene production. Conversely, pretreatment of wheat leaves with abscisic acid ABA 77 reduced ethylene production to levels of non-stressed leaves, accompanied by a decrease in ACC 71 content, Eq. (29). 

The modeling of residual stress development during cure can be used to optimize the processing conditions to reduce or control residual stresses. The current process model is used next to assess the effects of several processing conditions on residual stresses. Reduced cure temperature, longer dwell times, slower cool down rate, and the use of novel cure cycles are all feasible for the reduction of residual stresses. 

Water stress reduces the rate of photosynthesis in plants. In soybean crops, water stress leads to a loss of root integrity. The failure of the lower leaves to intercept light in a mature crop is compounded by the water-related limitations. The result is that lower leaves abscise and, because seed pods (yield) are supplied with assimilate mainly from leaves at the same nodal position on the stem, they in turn are lost and overall yield is reduced. The control of water stress in crops is a major PGR target in yield maintenance. The alleviation of water stress in developing crops, particularly in arid areas, is also desirable. 

Viscoelastic behavior is classified as linear or non-linear according to the manner by which the stress depends upon the imposed deformation history (SO). Insteady shear flows, for example, the shear rate dependence of viscosity and the normal stress functions are non-linear properties. Linear viscoelastic behavior is obtained for simple fluids if the deformation is sufficiently small for all past times (infinitesimal deformations) or if it is imposed sufficiently slowly (infinitesimal rate of deformation) (80,83). In shear flow under these circumstances, the normal stress differences are small compared to the shear stress, and the expression for the shear stress reduces to a statement of the Boltzmann superposition principle (15,81) ... 

The finite-element method applied in the elastic-plastic mode gives satisfactory predictions of the achievable improvements from autofrettage. As the residual stresses reduce efficiently the initiation and the growth of cracks, autofrettage is especially well useful for components... 

With the aid of the two-color Laser-Doppler-Anemometry (LDA), Bewersdorff was able to measure the axial and the radial turbulence intensities simultaneously and also the Reynolds shear stresses. The injection of polymer results in a damping of both intensities in the region of their maxima. In his Reynolds shear stress measurements he showed that the polymer injection results in a drastic damping, and the stress maximum is shifted towards the center of the pipe. In a homogeneous polymer solution the maximum of the Reynolds shear stress remains in the same position-as for water. Only in the region of the buffer zone are the shear stresses reduced. 

The fact is that sulfuric acid is an excellent low cost method of reducing the risk of carbonate scaling and often permits higher cycles of concentration in a cooling system than might otherwise be available. These features of sulfuric acid have benefits such as lower system stress, reduced water and chemical treatment consumption, and probably a lower maintenance cost. To achieve these benefits, good control over acid dosing and pH is required, as discussed above. 

Knock-out Impaired cardiac contractility in response to (3-adrenergic stimulation and hemodynamic stress Reduced anxiety-related responses and increased exploratory drive in male KO mice Prolonged Q-T intervals, reduced Ca2+-induced Ca2+ release upon 3-adrenergic stimulation. 

In Eyring s theory, yielding occurs by stress and temperature-activated jumps of molecular segments (McCrum et al., 1992). The applied stress reduces the activation barrier (AH) and segment motions define an activation volume, V. ... 

Oxidative stress reduces the rate of cell proliferation, and that occurring during chemotherapy may interfere with the cytotoxic effects of antineoplastic drugs, which depend on rapid proliferation of cancer cells for optimal activity. Antioxidants detoxify ROS and may enhance the anticancer effects of chemotherapy. For some supplements, activities beyond their antioxidant properties, such as inhibition of topoisomerase II or protein tyrosine kinases, may also contribute. ROS cause or contribute to certain side effects that are common to many anticancer drugs, such as gastrointestinal toxicity and muagenesis. ROS also contribute to side effects that occur only with individual agents, such as doxorubicin-induced cardiotoxicity, cisplatin-induced nephrotoxicity, and bleomycin-induced pulmonary fibrosis. Antioxidants can reduce or prevent many of these side effects, and for some supplements the protective effect results from activities other than their antioxidant properties. Certain side effects, however, such as alopecia and myelosuppression, are not prevented... 

Methaqualone was originally prescribed for the treatment of insomnia and anxiety disorders. It was also prescribed as an alleged stress reducer. ... 

Since nonreactive diluents do not enter into the crosslinking reaction, they can be lost due to volatilization, especially when exposed to the elevated temperatures of the exotherm or curing cycle. If vaporization does occur, shrinkage of the adhesive film can result in internal stresses being generated within the joint. These internal stresses reduce the degree of adhesion that is realized on final cure. 

The main reason MDMA has little abuse potential is that it exhibits tachyphylaxis —a rapid buildup of tolerance so that repeated usage within a short space of time leads to the loss of desired effects. In contrast to its "heart-opening" and stress-reducing qualities, this substance, if taken within a few days of a prior ingestion, tends paradoxically to produce an increase in stress and many of the least desirable characteristics of amphetamine overdosage. Very few people are attracted to such effects, and even those who are could achieve them more cheaply via other substances. 

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