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The studyofthehealingpowerofchemicalcompounds, present into the
known natural active principles and its subsequent use, shall be
seen initially as a pseudoscientificprocedure,
acontinuationoftheChineseandArabianoccultism, whichwasbased
inthepercentagecontentoffire, air, earthandwater, aswellas
ontheassociatedqualities: hot-cold, humid-dry. . .,
whichthematterwassupposed to be formed by. Themethod,
possessingroots in Hippocrates, Dioscoridesand Galen was studied,
described and polished by Avicenna, Averrot s, Bacon and Villanova
inthe MiddleAge. Italsowasappearingasastudyconstantduringthe
renaissance and after. On the other hand, the birthofchemistry
asascientific offspring from alchemy propitiated alternative ways
ofknowledge in order to solve the same problem. In this manner, in
the past century, approximately hundred years from now, Sylvester
proposed the first molecular description in numerical discrete
form, employing ideas which even in present times can be associated
withinthesocalledmoleculartopology. Sylvester'stopologicalmodel can
be considered the seed allowing the originofthis big tree, which is
now knownastheoreticalchemistry. . During all the past time from
the first topological modelofSylvester up to now, the
proliferationofnumerical parameters to describe molecular
structures has not ceased to grow larger. Some ofthese parameters
have played a very important role for the understandingofthe
organic molecules behavior and, by extension, for the comprehension
and evaluation of their physical as well as biologicalproperties.
InthemindofeveryspecialistaretheHammett'scr, theTaft constantsor
the octanol-water partition coefficient. Other numerical
parameters,
suchasthosederivedfromthemodemtopologicalmolecularrepresentationarein
aprocessofconstantrevisionandgrowing. Thus,
theHosoyaandRandicindices, ortheKier'sconnectivities,
amongseveralnotsowellknownnumericaldataare usual reference
descriptors. They are putatthe researchers' disposition, andare
easily deducible from any molecular representation in form
ofordered setsof numerical figures. All ofthem are profusely
studied and employed in present times. The main idea consists into
the useofthese numerical data in orderto
obtaininformationonthemoleculartrendstopossessoracquirecertainproperties
and, even better than this, to determine in which degree or
intensity molecules presenteverything.
This much-needed book describes the digital home networking
environment, its techniques, and the challenges around its service
architecture. It provides a broad introduction to state-of-the-art
digital home standards and protocols, as well as in-depth coverage
of service architectures for entertainment and domotic services
involving digital home resources. Topics include networking, remote
access, security, interoperability, scalability, and quality of
service. Notably, the book describes the generic architecture that
was proposed and developed in the context of the EUREKA/Celtic
research project Feel@Home.
The aim of this text is to provide reviews and monographs on topics
involving molecular similarity, ranging from the fundamental
physical properties underlying molecular behaviour to applications
in industrially important fields such as pharmaceutical drug design
and molecular engineering. The editors hope that this series will
encourage new ideas and approaches, help to systematize the rapidly
accumulating new chemical information, and make chemistry better
understood and better applied.
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