Findings nature

It is well established that the enzymes for the aerobic degradation of PCBs can be induced by biphenyl. Efforts have therefore been made to find naturally occurring metabolites that wonld fnnction as inducers, and whether plants are able to exert a beneficial effect. The pntative role of terpenoids in inducing the degradation of PCBs has been noted in Chapter 9, Part 2 and Chapter 12. 

Further progress can be expected in the area of selective inhibition and inactivat-iem of cellulases undesirable in xylanase preparations. There is a possibility of finding natural selective cellulase inhibitors or developing highly reactive derivatives of cello-biose and cellodextrins that inactivate cellulolytic enzymes. 

Since the 1950s, using a different approach, the U.S. National Cancer Institute, as well as agencies in other countries, has sought to find natural anticancer compounds in plants, fungi, microorganisms, and marine invertebrates. Among these are many antibiotics that intercalate into DNA helices, e.g.,... 

Another problem or consideration that may interfere with some aspects of allelopathy (especially in field experiments) has arisen over the past fifty years with the introduction and use of a multitude of xenobiotic compounds as insecticides, fungicides, plant growth regulators, harvest aids, and herbicides. A variety of such compounds have been and continue to be used on a world-wide scale. Some of these chemicals and/or their transformation products are persistent in soils and water. Other such chemicals are routinely applied at various times during a year. These xenobiotics may interfere or interact with naturally occurring allelochemics and thus alter or even mask certain natural allelochemical effects. Researchers will have a more difficult time to find natural areas that do not contain xenobiotic... 

Clustering attempts to find natural groups as determined by the metric used (Euclidean distance, cosine distance, or categorical attributes) which are blind as to treatment. These types of techniques are particularly useful for discovering new relationships among variables and for the derivation of measurement data based on natural differentiations and not the bias of the observer. The use of these techniques to determine assessment and measurement endpoints has been extensively discussed (Landis et al. 1994). 

Wallace, R. and Kanade, T. (1990). Finding Natural Clusters Having Minimal Description Length, In Proceeding of the 1990 IEEE Conference on Pattern Recognition, 438-442, Atlantic City, NJ. 

But are all recognised speoies always individuals I don t think so. If we simplify the concepts to natural species are individuals and artificial species are classes, then we nay end up in a flora with a mixture of natural and artificially delimited species, and we cannot tall the difference Because of the limitations of the auseua-and herbarium-methods, we cannot know all aspects. And this has the consequence that we still don t know whether all recognized species are true species. My sceptical colleague was partly right. The conclusion should be that characters do not provide 100% certainty as reliable toole to find natural (i.e. phylogenetic) relations. 

The vast body of literature on electrochemical oscillations has revealed a quite surprising fact dynamic instabilities, manifesting themselves, for example, in bistable or oscillatory reaction rates, occur in nearly every electrochemical reaction under appropriate conditions. An impressive compilation of all the relevant papers up to 1993 can be found in a review article by Hudson and Tsotsis. This finding naturally raises the question of whether there are common principles governing pattern formation in electrochemical systems. In other words, are there universal mechanisms leading to self-organization phenomena in systems with completely different chemical compositions, and thus also distinct rate laws ... 

The positive agronomic characteristics of these endophytic associations have recently led to efforts to commercialize them. The ability to find natural associations, coupled with an ability to identify and maintain them in plant germplasm collections (Clement, 2000), will continue to be important. Current commercialization efforts have pursued several strategies and will potentially increase in both scope and number in the future. 

Although no commercial product has resulted thus far, it is obvious that finding natural nontoxic associations within a grass species and using selection to... 

Well-established concepts in one area of science often find natural applications in other areas of science. In this regard, physics plays a pivotal role. Investigations in physics focus, for the most part, on systems with small number of actual or reduced variables and lead to firmly established concepts and fundamental laws. It is thus natural for chemistry to look into physics for guidance as it explores the unknown territories. The main thesis of the article is that physical laws are about limitations. While they set the boundaries within which chemical mechanisms must fall, they cannot dictate the actual mechanisms. Thus, chemistry has to be viewed as both dependent and independent of physics. The relation between physics and other areas of scientific inquiry is likely to follow the pattern described here within the possibilities allowed by physics, scientists have to look for explanations that depend on factors outside physics. 

The inference is that organic enzymatic catalytic activity and carcinogenicity may share a common electrophilic ancestry. If this indeed has a bearing on anticancer agents, the resolntion can be phrased in terms of finding natural or synthetic... 

The problem is to find natural conditions on the functor F to ensure that it is isomorphic to a functor of the type hjp. For example, let me mention one property of all the functors h which was discovered by Grothendieck (Compatibility with faithfully flat descent) ... 

Unsupervised classification - Cluster analysis. Unsupervised classification or cluster analysis is a way to find natural patterns in a data set. There are no independent true answers that can guide the classification and we are therefore restricted to construct a set of criteria or general rules that can highlight the interesting patterns in a data set. A data set consists usually of a set of objects that each are characterised by a feature vector x. To find patterns it is important to establish to what degree vectors are similar to each other. Similarity is often defined using a distance metric between object i and j... 

To find the natural log of a number using a calculator, the number is entered and then thenrD key is pressed. Use the following examples to check your technique for finding natural logs with your calculator ... 

Stacker. In the angiogenesis area there is a big push to find natural promoters of the inhibitors. 

Do you think there is much chance of finding natural mineral deposits of calcium or magnesium bicarbonates ... 

Chapter 1 considers the possible relationships of earthly clays and other minerals to the origin of chirality in organic molecules. Attempts to establish experimental evidence of asymmetric adsorption on clays were unsuccessfiil, but die search for chirality did find naturally occurring enantiomorphic crystals like quartz. Asymmetric adsorption of organic molecules on quartz crystals such as separation of racemic mixtures, like Co or Cr complexes, alcohols and other compounds, allowed for the conclusion that quartz crystals can serve as possible sources of chirality but not of homochirality. This latter conclusion results fi om the finding that all studied locations of quartz crystals contain equal amounts of d- and /-forms. The preparations of synthetic adsorbents such as imprinting silica gels are also considered. More than 130 references are analyzed. 

---