Regulatory and functional interaction of vasoactive factors in the kidney and extracellular pH

Regulatory and functional interaction of vasoactive factors in the kidney and extracellular pH. A growing body of evidence suggests that vasoactive factors produced in the kidney such as nitric oxide, endothelins, angiotensin, and prostaglandins participate actively in the regulation of acid-base homeostasis under physiologic conditions. In addition, recent reports indicate that alterations in the systemic acid-base status may also influence the generation of vasoactive cytokines in the kidney, which in turn may mediate the renal effector processes that tend to restore normality under such conditions. Metabolic acidosis, which so frequently accompanies many forms of chronic renal failure (CRF), may contribute to down-regulation of intrarenal nitric oxide production that characterizes CRF. Reduced extracellular pH inhibits inducible nitric oxide production in mesangial cells by altering the reduced form of nicotinamide adenine dinucleotide phosphate (NADPH) oxidation, an important posttranslational mechanism in the inducible nitric oxide synthase (iNOS) activation. The underlying defects resulting in the uncoupling of NADPH oxidation in acidemic microenvironment are discussed. Acidosis stimulates renal production of endothelins, which mediate proximal tubular acidification by enhancing sodium-hydrogen exchanger-3 (NHE-3) activity. Renal endothelins mediate enhanced urinary acid excretion following dietary acid ingestion, an effect that is effectively blocked by endothelin receptor blockers. Reduced extracellular pH stimulates endothelin secretion from renal microvascular endothelial cells, which may promote enhanced acid excretion from the distal tubule under conditions of acidosis. These phenomena as well as the role of angiotensin and renal prostaglandins in mediating renal acidification in normal and acidotic conditions are discussed in this review, which describe the regulatory interaction between extracellular pH and renal vasoactive factors

Stronger Tradeoffs for Orthogonal Range Querying in the Semigroup Model

In this paper, we focus on lower bounds for data structures supporting orthogonal range querying on m points in n-dimensions in the semigroup model. Such a data structure usually maintains a family of "canonical subsets" of the given set of points and on a range query, it outputs a disjoint union of the appropriate subsets. Fredman showed that in order to prove lower bounds in the semigroup model, it suffices to prove a lower bound on a certain combinatorial tradeoff between two parameters: (a) the total sizes of the canonical subsets, and (b) the total number of canonical subsets required to cover all query ranges. In particular, he showed that the arithmetic mean of these two parameters is Omega(m log^n m). We strengthen this tradeoff by showing that the geometric mean of the same two parameters is Omega(m log^n m). Our second result is an alternate proof of Fredman\u27s tradeoff in the one dimensional setting. The problem of answering range queries using canonical subsets can be formulated as factoring a specific boolean matrix as a product of two boolean matrices, one representing the canonical sets and the other capturing the appropriate disjoint unions of the former to output all possible range queries. In this formulation, we can ask what is an optimal data structure, i.e., a data structure that minimizes the sum of the two parameters mentioned above, and how does the balanced binary search tree compare with this optimal data structure in the two parameters? The problem of finding an optimal data structure is a non-linear optimization problem. In one dimension, Fredman\u27s result implies that the minimum value of the objective function is Omega(m log m), which means that at least one of the parameters has to be Omega(m log m). We show that both the parameters in an optimal solution have to be Omega(m log m). This implies that balanced binary search trees are near optimal data structures for range querying in one dimension. We derive intermediate results on factoring matrices, not necessarily boolean, while trying to minimize the norms of the factors, that may be of independent interest

Trace Elements in Dentistry: A Review

As human body needs in and around two thirds of all the elements so as to maintain the health and our human body contains elements which are well known as abundant elements as well as trace elements. Due to biological and chemical reactions, trace elements, being part of a few enzymesare very important. They work not in collaboration with proteins but definitely with other co-enzymes. At earlier stage dental profession was involved with the field of trace elements and their association with dental disease. So, understanding of these trace elements is essential and significant for disease control as well as for optimal health

Environmental and Health Impacts of Electronic Waste: A Global Concern!!

Electronic waste, commonly referred as e-waste, is waste generated from discarded waste from an alarming number of electronic components which contains toxic substances affecting human health and the environment across the globe. In India, it is of extreme significance as its huge production uses more electronic materials and thus, dumps a significant amount of  e-waste simultaneously. India is still lacking suitable infrastructure and methods is proper recycling and disposal. This review is an overview of current scenario in the developing countries, India and other countries  depicting the magnitude of environmental and health hazards associated with improper recycling and disposal methods

Study of machine parameters in twin-screw extruder for pulses based extrudate

Legumes are prime source of plant proteins, calories and other nutrients. Extrusion cooking of legumes increases the digestibility of legume protein. Extrusion technology has been applied to generate analogues of foods made from animal products, as well as snacks using blends of various plant raw materials e.g. oil seeds [soybeans, peanut with a cereal flour]. Present work was under taken for producing extruded product from pigeon pea. The legumes viz. pigeon pea and Bengal gram were cleaned and ground to required particle size by multipurpose grinder mill to pass through sieve ASTM No. 20. The moisture content of sample was adjusted to 14% moisture level (w.b.). Before extrusion, the feed was allowed to come to ambient temperature and then remixed, after checking its moisture content. The twin-screw food extruder was used and then different extrudates were prepared using feed rate and feed moisture. The effect in incorporation of dehulled pigeon pea product character tics was studied. The bulk density and tapping density of pigeon pea flour was found to be 0.4809×10-3 g/mm3 and 0.719×10-3 g/mm3 respectively. Then the moisture content of pigeon pea flour was calculated and found to be 9.08% (w.b.) and different sample were prepared of 14% and 20% (w.b.). Now the thousand kernels was determined and found to be at average of 30.778. The dimension were taken on the basis of length, width, and thickness and calculated at the average of 4.47 mm, 4.221 mm, and 1.82 mm