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Hx materialism

Materialism began...

The Materialism of Epicurus (c. 341-271 BCE)
…the whole of being consists of bodies and space. For the existence of bodies is everywhere attested by sense itself, and it is upon sensation that reason must rely when it attempts to infer the unknown from the known. And if there were no space (which we call also void and place and intangible nature), bodies would have nothing in which to be and through which to move, as they are plainly seen to move. Beyond bodies and space there is nothing which by mental apprehension or on its analogy we can conceive to exist. When we speak of bodies and space, both are regarded as wholes or separate things, not as the properties or accidents of separate things.
…the first beginnings must be indivisible, corporeal entities.
…the atoms, which have no void in them—out of which composite bodies arise and into which they are dissolved—vary indefinitely in their shapes; for so many varieties of things as we see could never have arisen out of a recurrence of a definite number of the same shapes. The like atoms of each shape are absolutely infinite; but the variety of shapes, though indefinitely large, is not absolutely infinite…
The atoms are in continual motion through all eternity. Some of them rebound to a considerable distance from each other, while others merely oscillate in one place when they chance to have got entangled or to be enclosed by a mass of other atoms shaped for entangling….
Moreover, there is an infinite number of worlds, some like this world, others unlike it…
… For the atoms out of which a world might arise, or by which a world might be formed, have not all been expended on one world or a finite number of worlds, whether like or unlike this one. Hence there will be nothing to hinder an infinity of worlds.
Letter to Herodotus


salt

References



Lexicon

NB: Starting work here on 'lexicon' to replace the 'External Article', Lexicon.

Among its many usage senses, the word 'lexicon' refers to the vocabulary of a language — the language's complete set of words — where 'language' may include the language of a cultural or national group (e.g., the lexicon of the Navajo language, of the the French language); the language of a person (e.g., the lexicon of Malcom X); the language of a distinguishable group of people (e.g., the lexicon of plumbers, of physicists, of chefs); the language of a definable subject (e.g., the lexicon of environmentalism, of economics, of philately); the language of a particular collection of documents (e.g., the lexicon of the Hippocratic Treatises, of U.S tax law, of the works of James Joyce); and, any other spoken or written language of individualized character. [1] The words 'word' and 'language' in that sense of 'lexicon' assumes the common understanding of their meaning, but require understanding of their technical meaning in linguistics.

Two usage examples of 'lexicon' here, from Wordsmith:

The word dehiscence is one of the most vexing words in the surgeon's lexicon. When a post-op patient "dehisces", one or more of the tissue layers of the incision have come apart.[2]

Psychobabble [psychiatric jargon-laden language] is ... a set of repetitive verbal formalities that kills off the very spontaneity, candor, and understanding it pretends to promote. It's an idiom that reduces psychological insight to a collection of standardized observations, that provides a frozen lexicon to deal with an infinite variety of problems.[3]

refs

  1. Entry for 'lexicon' in Webster's Third New International Dictionary, Unabridged. Merriam-Webster, 2002.
  2. Comment by Lee Sataline, MD, Wordsmith.org
  3. Citing Richard Dean Rosen, 1977.

Test OpenOffice-Constructed Table Exported to MediaWiki Markup

TABLE TEST-4
 
CONSTRUCTED IN MS-WORD-LIKE OPEN-OFFICE TEXT DOCUMENT,
SAVED, THEN EXPORTED TO MEDIAWIKI MARKUP TXT FILE,
OPENED IN TEXT EDITOR, COPY ALL, PASTE IN MEDIAWIKI EDITOR
NAME
DATE
PLACE
SIZE
COLOR
Johna
Wed
June 7, 1234
China
50 feet
shiny
Bob
Tue
May 15, 1900
Japan
32.4 cm3
spectral
Bill
Tue
December 12, 2000
Moonb
larger
black
Jim
Thu
December 13, 2001
Titan
big
turquoise
Alexander
Wed
November 14, 1100
Everywhere at
the same time
of day or night
4 nanometers
puce

a John Browne, of Baylye; b Earth's Moon, Luna

wrd2oo

DATE
PLACE
PERSON
COST
07-Jul-2010
Russia
Mendeleev
$49
09-Aug-1950
Madagascar
Hippocrates of Kos
$56789
01-Jan-1234
Stratford-On-Avon
Robert Elliot Bryne Smyth Shakespeare III
$5
09-Sep-1492
Little Big Horn
Bob
$0.45679

The Journal of Theoretical Biology

The editors of the Journal of Theoretical Biology emphasize the role of theory in giving insight to biological processes: [1]

The Journal of Theoretical Biology is the leading forum for theoretical papers that give insight into biological processes. It covers a very wide range of topics and is of interest to biologists in many areas of research. Many of the papers make use of mathematics, and an effort is made to make the papers intelligible to biologists as a whole. Experimental material bearing on theory is acceptable…. Research Areas Include: Cell Biology and Development; Developmental Biology; Ecology; Evolution; Immunology; Infectious Diseases; Mathematical Modeling, Statistics, and Data Bases; Medical Sciences and Plant Pathology; Microbiology; Molecular Biology and Biochemistry; Physiology.  [1]

A listing of the ten most downloaded articles from the journal (in agricultural and biological sciences) give an indication of the kinds of theoretical and conceptual approaches and topics that interest theoretical biologists: [2]

  • Thermodynamics of natural selection I: Energy flow and the limits on organization
  • Biofilms in the large bowel suggest an apparent function of the human vermiform appendix
  • Modeling the segmentation clock as a network of coupled oscillations in the Notch, Wnt and FGF signaling pathways
  • Thermodynamics of natural selection II: Chemical Carnot cycles
  • A protein interaction network associated with asthma
  • Self-organization at the origin of life
  • The timing of TNF and IFN-@c signaling affects macrophage activation strategies during Mycobacterium tuberculosis infection
  • Thermodynamics of natural selection III: Landauer's principle in computation and chemistry
  • Prevention of avian influenza epidemic: What policy should we choose?
  • Evolutionary stability on graphs

The corresponding top ten downloads in the areas of biochemistry,genetics and molecular biology: [3]

  • The Epithelial-Mesenchymal Transition Generates Cells with Properties of Stem Cells
  • Induction of Pluripotent Stem Cells from Adult Human Fibroblasts by Defined Factors
  • Direct Reprogramming of Terminally Differentiated Mature B Lymphocytes to Pluripotency
  • Induction of Pluripotent Stem Cells from Mouse Embryonic and Adult Fibroblast Cultures by Defined Factors
  • SnapShot: Hematopoiesis
  • Nuclear Receptor-Enhanced Transcription Requires Motor- and LSD1-Dependent Gene Networking in Interchromatin Granules
  • The Hallmarks of Cancer
  • TGF@b Primes Breast Tumors for Lung Metastasis Seeding through Angiopoietin-like 4
  • Acetylation Is Indispensable for p53 Activation
  • An Extended Transcriptional Network for Pluripotency of Embryonic Stem Cells

It appears from the titles alone that currently theoretical biology covers a widely diverse types of subject matter, not all qualifying as mathematical or philosophical biology.

The National Academies' National Research Council report on theoretical biology

A committee of the National Research Council of the National Academies reported in 2008 on “The Role of Theory in Advancing 21st-Century Biology: Catalyzing Transformative Research.” [4] In the summary of their report they speak to the nature of theoretical biology:

The committee was charged with examining the role of concepts and theories in biology, including how that role might differ across various subdisciplines. One facet of that examination was to consider the role of the concepts and theories in driving scientific advances and to make recommendations about the best way to encourage creative, dynamic, and innovative research in biology....The committee concluded that a more explicit focus on theory and a concerted attempt to look for cross-cutting issues would likely help stimulate future advances in biology. To illustrate this point, the committee chose seven questions to examine in detail. The list of questions is not comprehensive but rather illustrative. The questions, as shown below, were chosen to show that a focus on theory could play a role in helping to address many different types of interesting and important questions at many different levels. [4]

In the Table of Contents of the committee's report,  [4] they center report around these questions:

  • Are There Still New Life Forms to Be Discovered? The Diversity of Life - Why It Exists and Why It's Important (38-66)
  • What Role Does Life Play in the Metabolism of Planet Earth? (67-80)'
  • How Do Cells Really Work? (81-89)
  • What Are the Engineering Principles of Life? (90-109)
  • What Is the Information That Defines and Sustains Life? (110-129)
  • What Determines How Organisms Behave in Their Worlds? (130-144)
  • How Much Can We Tell About the Past - and Predict About the Future - by Studying Life on Earth Today? (145-156)

Achieving answers to those kinds of questions would seem to require interdisciplinary collaboration among many different biological and non-biological scientific disciples, which brings a diversity of concepts, hypotheses, and theories.

The NRC committee emphasized the integral role of theory in biology, in chapter so titled, and selected for the chapter's epigraph a quote from Leonardo da Vinci: "He who loves practice without theory is like the sailor who boards ship without a rudder and compass and never knows where he may cast. The first chapter, broken to bullet sentences, serves to summarize their conclusion:

  • This chapter:
  • describes several different ideas about scientific theories,
  • emphasizes the diversity of theoretical activities throughout biology, and
  • discusses ways in which theory is integral to each specific kind of scientific activity, including
  • experimentation,
  • observation,
  • exploration,
  • description, and
  • technology development as well as
  • hypothesis testing.
  • Biologists use a theoretical and conceptual framework to inform the entire scientific process, and they frequently advance theory even when their work is not explicitly recognized as theoretical.
  • Explicit recognition of the many entry points of theory into the scientific enterprise may provide greater opportunity for developing
  • new concepts, principles, theories, and perspectives in biology that would
  • not only enhance current scientific practices
  • but also facilitate the exploration of cross-cutting questions that are difficult to address by traditional means. [4]

The committee makes a specific recommendation:

Theory, as an important but under appreciated component of biology, should be given a measure of attention commensurate with that given other components of biological research (such as observation and experiment). Theoretical approaches to biological problems should be explicitly recognized as an important and integral component of funding agencies’ research portfolios. Increased attention to the theoretical and conceptual components of basic biology research has the potential to leverage the results of basic biology research and should be considered as a balance to programs that focus on mission-oriented research. [4]

refs

  1. 1.0 1.1 Journal of Theoretical Biology: About Us.
  2. Top 25 Hottest Articles, Agricultural and Biological Sciences, Journal of Theoretical Biology, April-June 2008.
  3. Top 25 Hottest Articles, Biochemistry, Genetics and Molecular Biology, Journal of Theoretical Biology, April-June 2008.
  4. 4.0 4.1 4.2 4.3 4.4 National Research Council of the National Academies, Division of Earth and Life Studies, Board on Life Sciences, Report of the Committee on Defining and Advancing the Conceptual Basis of Biological Sciences in the 21st Century. (2008) Role of Theory in Advancing 21st-Century Biology: Catalyzing Transformative Research. The National Academies Press. Washington, D.C.

Test 091708-1846

— Reaction Type —
— Definition —
— Representative Examples —
— Comments —
  OXIDATION  
-- loss of electrons --
(oxidation = 'de-electronation')
K → K+ + e-
O2•- → O2 + e-
oxidation of a potassium atom to a potassium ion
oxidation of a superoxide radical to oxygen
OXIDATION
-- loss of electron with hydrogen nucleus --
--
examples depend on the atom or molecule that accepts the hydrogen atom
OXIDATION
-- gain of oxygen --
C + O2 → CO2
oxidation of carbon to carbon dioxide
(the more electronegative oxygen obtains greater share of carbon's electrons)
REDUCTION
-- gain of electrons --
(reduction = 're-electronation')
Cl + e- → Cl-
O2 + e- → O2•-
reduction of a chlorine atom to a chloride ion
reduction of an oxygen molecule to a superoxide radical
REDUCTION
-- gain of electron with a hydrogen nucleus --
C +2H2 → CH4
reduction of a carbon atom to a methane molecule
(the carbon atom gains electrons it shares with a hydrogen nucleus)
REDUCTION
-- loss of oxygen --
CO2 + C → 2CO
reduction of carbon dioxide to carbon monoxide
concomitant oxidation of carbon to carbon monoxide

Test 090908-1937


<a id="s1"></a>

The Future Is Now

The world is an untidy place, and the sciences—all of them—reflect this. One source of this untidiness is the relationship between levels of organization. Reducing macrolevels to microlevels—explaining the former in terms of the latter—has met with successes but has never been the whole story. In the biological sciences, there has been much attention lately to the shortcomings of reductionism on the grounds that (i) it changes the subject rather than explaining, (ii) it leads to a myopically molecular view of the biological world, and (iii) the behavior or behaviors of complex systems are often very poorly predicted based solely on their microproperties. It is just for these reasons that biologists of many stripes have called for a move away from reductionism and toward a new kind of biology for the 21st century. But what shape might this new biology take?

A look at the recent literature reveals that the new biology should be mathematical in nature, partly because of needed improvements in modeling the outcomes of interactions between levels of organization [<a href="#journal-pbio-0050181-b001">1</a>]. The new biology should be integrative across levels of organization while remaining attentive to differences in kinds and degrees of causal factors [<a href="#journal-pbio-0050181-b002">2</a>]. It should also attend to the holistic, nonlinear, and emergent features of the biological world, focusing primarily on “evolution and the nature of biological form” [<a href="#journal-pbio-0050181-b003">3</a>]. The new biology should also move “away from a reductionist focus on a limited number of molecular components to a comprehensive understanding of how large numbers of interrelated components of a system comprise modules or networks whose functional properties emerge as definable phenotypes” (<a href="http://www.systemsbiology.org">http://www.systemsbiology.org</a>). Its approaches “should be more integral, multilevel, and dynamic” than they are presently [<a href="#journal-pbio-0050181-b004">4</a>]. It should also offer new theoretical insights that help make sense of and integrate the vast amounts of data being produced by biologists in many fields [<a href="#journal-pbio-0050181-b005">5</a>].

Test 090908-1946

<hr noshade="noshade" size="1" width="100%">

<!-- start: body -->

<a id="s1"></a><h3>The Future Is Now</h3><p>The world is an untidy place, and the sciences—all of them—reflect this. One source of this untidiness is the relationship between levels of organization. Reducing macrolevels to microlevels—explaining the former in terms of the latter—has met with successes but has never been the whole story. In the biological sciences, there has been much attention lately to the shortcomings of reductionism on the grounds that (i) it changes the subject rather than explaining, (ii) it leads to a myopically molecular view of the biological world, and (iii) the behavior or behaviors of complex systems are often very poorly predicted based solely on their microproperties. It is just for these reasons that biologists of many stripes have called for a move away from reductionism and toward a new kind of biology for the 21st century. But what shape might this new biology take?</p><p>A look at the recent literature reveals that the new biology should be mathematical in nature, partly because of needed improvements in modeling the outcomes of interactions between levels of organization [<a href="#journal-pbio-0050181-b001">1</a>]. The new biology should be integrative across levels of organization while remaining attentive to differences in kinds and degrees of causal factors [<a href="#journal-pbio-0050181-b002">2</a>]. It should also attend to the holistic, nonlinear, and emergent features of the biological world, focusing primarily on “evolution and the nature of biological form” [<a href="#journal-pbio-0050181-b003">3</a>]. The new biology should also move “away from a reductionist focus on a limited number of molecular components to a comprehensive understanding of how large numbers of interrelated components of a system comprise modules or networks whose functional properties emerge as definable phenotypes” (<a href="http://www.systemsbiology.org">http:<wbr alt="​" style="content: attr(alt);" />/<wbr alt="​" style="content: attr(alt);" />/www.systemsbiology.org</a>). Its approaches “should be more integral, multilevel, and dynamic” than they are presently [<a href="#journal-pbio-0050181-b004">4</a>]. It should also offer new theoretical insights that help make sense of and integrate the vast amounts of data being produced by biologists in many fields [<a href="#journal-pbio-0050181-b005">5</a>].</p>

Alcmaeon

Alcmaeon, an ancient Greek natural philosopher interested in particular in medicine and physiology, lived sometime around 500 B.C.E., during and close to the time of Pythagorus (ca. 570 – 490 B.C.E.) and Hippocrates (470 – ca. 370 B.C.E.). Scholars have fragmentary extant writings of Alcmaeon’s, but his ideas did not die with him. According Galen, Alcmaeon authored a book, On Nature, to which, before it disappeared, Aristotle, Theophrastus, and others had direct access for some time after Alcmaeon’s death. Alcmaeon’s ideas have earned him, according to some scholars the honorific, Father of Physiology, Father of Anatomy, Father of Psychology, Founder of Gynecology, Creator of Psychiatry, and indeed, by some, Father of Medicine.[1]

Andreas Vesalius’s biographer, C. D. O’Malley credits Alcmaeon as the earliest known “student of anatomy”:

The earliest known genuine student of anatomy appears to have been Alcmaeon of Crotona, who lived in southern Italy, c. 500 B.C. Only the slightest fragments of his writing remain, but from these it does appear that he was the first to make dissections of animals, probably goats, and although almost nothing is known of the results, he did make the very important declaration that the brain is the central organ of intelligence.   [2]

Christianity

In today's excerpt--in a Roman empire that was ruled by a small number of elites, heavily populated by slaves and the poor, and possessed of a flaccid paganism, Christianity grew from ten thousand believers in 100 CE to six million in 300 CE. It was the fastest spread of a religion in history until the rise of Islam in the sixth century CE. And it spread in spite of the difficulty of maintaining uniform beliefs given poor communication, poor literacy and wide geographical dispersion:

"Early Christianity was tiny and scattered. No precise figures survive, but best estimates suggest that there were considerably fewer than ten thousand Christians in 100 CE, and only about two hundred thousand Christians in 200 CE, dispersed among several hundred towns. The late-second-century figure equals only 0.3 percent of the total population of the Roman empire (which was about 60 million). ... The rapidity of its growth rate helps explain why coded statements of belief, rather than complex rules of practice, were the passport to full membership. The very small size of Christianity helps explain why the Roman state paid so little attention to suppressing it effectively. ...

"In the early stages of Christianity, at any one time, perhaps only a few dozen Christians could read or write fluently. On the numbers which I have just cited, and even if we allow for a significantly higher rate of literacy among Christians than among pagans (outside of the ruling elite), by the end of the first century all Christianity is likely to have included, at any one time, less than fifty adult men who could write or read biblical texts fluently. ...

"Religion was not a frontier along which the Roman elite considered it needed to defend itself with vigor, at least not until the middle of the third century. And when the state did attack the Christian church on a massive scale ... the number of Christians, in spite of temporary setbacks, continued to grow. ... By the end of the third century, perhaps 10 percent of the empire's population--6 million out of 60 million people--were Christians. The emperor Constantine openly converted to Christianity in 312, and the emperors who succeeded him were also Christian. ... It is difficult to decide whether this [turn of events], which had so much influence on the future course of western culture, should be called a triumph of the Christian church or the triumph of the Roman state.."

"What is amazing is that in spite of the practical difficulties of size, dispersion, rapid growth, and illegality, and in spite of the startling variety of early Christian beliefs, Christian leaders actively pursued and preserved the ideal of unity and orthodoxy.

Keith Hopkins, A World Full of Gods, Plume, Copyright 1999 by Keith Hopkins, 2001, pp. 82-84. ________________________________________

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Sun

Basic Facts About the Sun

From Intute: Science, Engineering and TechnologyThe Sun: A Nearby Star; The Sun: A Multi-Media Presentation; Astronomy 162: Stars, Galaxies, and Cosmology

Diameter (photosphere)

1,391,980 km; 864,936.272 miles

Mass

1.99 x 1030 kg
(Earth mass =5.976 x 1024 kg)

Volume

1.3 million Earth volumes

Average Density

1.41 g/cm3

Luminosity

3.83 x 1033 erg/sec

Light Emitted per cm2 surface ~that of 6,000 watt lamp
Rotation Period (equator) 25 days
Surface Temperature (effective) 5,800° K; 5,526.85° C
Core Temperature ~15,000,000° C
Spectral Class G2 V
Mean Distance (Earth) 149,597,892 km; 92,955,820 miles
Apparent Visual Magnitude - 26.7
Absolute Visual Magnitude + 4.8
Number of Elements Identified in Sun Spectrum ~60
Two Most Abundant Elements (% of Total Number Atoms) Hydrogen (92%); Helium (7.8%)
Only Other Elements Present at >0.01% Total Atoms Oxygen (0.06%); Carbon (0.02%)
'
'
'
'
'

text

test

In 1770, Dutch physicianjan Ingcnhousz (1730-1779) took up the issue in a series of over 500 well-planned experiments. These experiments authorita¬tively cleared up the issue when he published them in a 1779 book, Expert¬merits upon Vegetables. —J. Schectman[3]

In 1770, Dutch physicianjan Ingcnhousz (1730-1779) took up the issue in a series of over 500 well-planned experiments. These experiments authorita¬tively cleared up the issue when he published them in a 1779 book, Expert¬merits upon Vegetables. This book confirmed Pricsdey's findings about green plants and oxygen, and it also added light to the equation. For many years, scientists had observed that submerged plants give off tiny bubbles. The accepted explanation was that water simply "frees" trapped air from the leaves. Ingenhousz suspected a much more sophisticated process. After iso-lating many variables, Ingenhousz finally found that when he heavily shaded the plants in his laboratory, the bubbles stopped. He thought that the plants therefore required heat in order to produce the bubbles. But putting a flame next to them made no difference. Finally, Ingenhousz demonstrated that the plants gave off bubbles only on receiving sunlight. Delving further, Ingenhousz collected the gas that his plants gave off in sunlight. He found that it supported combustion brilliantly, and he correctly concluded that it was the same gas as Priestley's oxygen. However, when Ingenhousz collected the gas given while he shaded the plants, he was sur¬prised to learn that plants "injure" the air by making it unfit for combustion. He corrccUy concluded that this gas was the same as Black's carbon dioxide-long known to shut down combustion and respiration. Ingenhousz had dis¬covered the process by which green plants absorb carbon dioxide and emit oxygen when exposed to sunlight. He had also discovered that they reverse this process in heavy shade or darkness.

Today, this process is known as photosynthesis (see Figure 21), a word that means "putting together with light." Later in the century, Jean Senebier (1742-1809), a Swiss scientist, confirmed the discoveries of many of Ingcn-housz's experiments and as well as the general efficacy of his photosynthesis theory. Today, scientists widely accept Ingcnhousz's theory as valid. Curiously, none to date has been able to artificially replicate photosynthesis in a labo¬ratory setting. As a modern equation, photosynthesis appears as 6C02 + 6H20 + light energy —> C6H|206 + 602. Scientists also consider Ingenhousz the first to draw attention to the concept of interdependence between living creatures, such as plants and animals. Animals depend on plants for food and oxygen. Plants depend on animals for carbon dioxide, soil-enriching waste, and decomposed carcasses.

Notes re photosynthesis from Shectman

Shectman [4]

All the following subsubsections (===) copied from Shectman; here only for reference

Jan Ingenhousz discovers photosynthesis

1779: Jan Ingenhousz (1730 1779) publishes Experiments upon Vegetables. This book confirms Joseph Priestley's experiments on green plant respiration (see 1760s-1770s). More importantly, it details Ingenhousz's experimental discovery of the process now known as photosynthesis (one of the most important processes in nature). This is the process by which plants make carbohydrates from carbon dioxide and water, given the presence of chlorophyll and light. During this process, they also release oxygen as a by-product, which is essential for animal survival.

In 1770, Dutch physicianjan Ingcnhousz (1730-1779) took up the issue in a series of over 500 well-planned experiments. These experiments authorita¬tively cleared up the issue when he published them in a 1779 book, Expert¬merits upon Vegetables. This book confirmed Pricsdey's findings about green plants and oxygen, and it also added light to the equation. For many years, scientists had observed that submerged plants give off tiny bubbles. The accepted explanation was that water simply "frees" trapped air from the leaves. Ingenhousz suspected a much more sophisticated process. After iso-lating many variables, Ingenhousz finally found that when he heavily shaded the plants in his laboratory, the bubbles stopped. He thought that the plants therefore required heat in order to produce the bubbles. But putting a flame next to them made no difference. Finally, Ingenhousz demonstrated that the plants gave off bubbles only on receiving sunlight. Delving further, Ingenhousz collected the gas that his plants gave off in sunlight. He found that it supported combustion brilliantly, and he correctly concluded that it was the same gas as Priestley's oxygen. However, when Ingenhousz collected the gas given while he shaded the plants, he was sur¬prised to learn that plants "injure" the air by making it unfit for combustion. He corrccUy concluded that this gas was the same as Black's carbon dioxide-long known to shut down combustion and respiration. Ingenhousz had dis¬covered the process by which green plants absorb carbon dioxide and emit oxygen when exposed to sunlight. He had also discovered that they reverse this process in heavy shade or darkness.

Today, this process is known as photosynthesis (see Figure 21), a word that means "putting together with light." Later in the century, Jean Senebier (1742-1809), a Swiss scientist, confirmed the discoveries of many of Ingcn-housz's experiments and as well as the general efficacy of his photosynthesis theory. Today, scientists widely accept Ingcnhousz's theory as valid. Curiously, none to date has been able to artificially replicate photosynthesis in a labo¬ratory setting. As a modern equation, photosynthesis appears as 6C02 + 6H20 + light energy —> C6H|206 + 602. Scientists also consider Ingenhousz the first to draw attention to the concept of interdependence between living creatures, such as plants and animals. Animals depend on plants for food and oxygen. Plants depend on animals for carbon dioxide, soil-enriching waste, and decomposed carcasses.

COLORED COLORED

Priestly

In 1772, English pneumatic chemist Joseph Priestley (1733-1804) docu¬mented the basic gaseous processes of plant respiration for the first time. He also explored the process now known as photosynthesis. In a scries of trials, Priestley showed that the same gas that supports animal respiration is given oil by green plants. He decided to investigate the matter much further. In a crucial investigation, Priestley enclosed a candle and the shoot of a green plant together in a laboratory container. Then, he burned the candle until the container's air would no longer support its flame. Priestley was careful not to burn the plant. He let several hours pass. When he was then able to burn the candle, Priestley concluded that the gas given off by the plant was the same gas that supported combustion.

Two years later in 1774, Priestley was surprised to rediscover his gas in the most unlikely of places. He had been conducting calcification (or oxidation) experiments in his laboratory for many months, with few useful results. One day, Priestley held his burning lens over a calx of mercury (or mercuric oxide). He collected the gas that this reaction released with an instrument known as a pneumatic trough. When he began tests on the gas, Priestley instantly recognized it as the same gas he had identified in plant respiration. In subsequent experiments, Priestley determined that this intriguing gas supported a mouse's respiration much longer than an equal volume of ordi¬nary air. Just as he thought, ihc gas also made a candle burn with a positively dazzling intensity. Priestley found the gas quite pleasant to breathe and not readily soluble in water. He broadly recommended its practical use in medical applications. A phlogistonist like Scheele, Priestley named his gas dephlo-gisticated air. He believed the gas had lost all its phlogiston and therefore hungrily grabbed it back from a burning object or a green plant. Several months later in 1774, Priestley traveled to Paris, where he was a popular figure due to his radical politics. Once there, he freely shared his discovery with the charismatic young chemist at the very center of the emerging chemical revolution, Antoine Lavoisier (1743-1794).

Hales

Throughout his experiments, Hales had been seeing evidence that sap docs not circulate in plants. In an exquisite, simple experiment (often repeated in modern botany courses), Hales demonstrated the direction of sap flow. He cut deep notches along the length and around the general circumference of a severed branch. Then he inserted the severed end in water. The branch adsorbed water with less success than an unnotched branch. Nonetheless, its leaves remained green. Hales correctly concluded that, because there was no line of passage between the branch's end and its leaves, sap had passed lat¬erally between sap vessels. Subsequent experiments provided no evidence of either evaporation or transpiration at any of the notches. This experiment demonstrated the power of transpiration and its effect on sap flow in all direc¬tions. It also showed conclusively that plants exhibit a progressive motion, rather than the circulatory one found in animals.

All along, Hales had noticed pockets of air in the sap, particularly that of vines. This engendered a scries of experiments of the mechanism by which plants draw air. These experiments were greatly overlooked at the time. It was only much later that scientists realized Hale had demonstrated that plants draw something specific from the air. It was even later that scientists identi¬fied this substance as carbon dioxide. (For more information, please see the entry on Plants Use Sunlight.) Vegetable Statute combined many disparate experiments into a coherent and cohesive system for the study of plants. Never before had rational experi-mentation, decisive analysis and functional equilibrium been applied to the study of plants. For these reasons, most scientists consider Hales the founder of plant physiology. For more than a century, little was done to equal Hales's work in this area. In fact, it took the combined work of many nineteenth-century scientists to discover vascular tissue. This tissue is comprised of two types of specialized cells called xylem and phloem. In 1914, Irish botanist Henry Dixon (1869-1953) proposed a compromise model to understand xylem, the hotly debated cells responsible for carrying water and minerals from root to leaf. Similarly, several scientists gradually discovered that phloem tissues carry food produced by leaf photosynthesis to other parts of the plant.

These were important discoveries, but the revolutionary work of plant physiology would ultimately depend on advances in the pneumatic chemistry of airs. The founder of pneumatic chemistry, Stephen Hales (1677-1761), published what became the classical text in plant physiology in 1727, Vegetable Statkks. Hales conducted hundreds of experiments on plants that demonstrated the flow of sap in the roots and stalks of plants as well as leaf-based evaporation of water (a process known as transpiration). Hales investigated the absorption of air and showed that it was not analogous to animal respiration as most scientists believed. However, Hales and other sci¬entists did not yet know that ordinary air was made up of several different gases. Hales thought plants were somehow able to modify the qualities of a single, highly clastic air.

Joseph Black

In 1754, Joseph Black (1728 1799) discovered the first distinct gas ever identified, when he isolated fixed air, or carbon dioxide, in his laboratory. Though it took the later interpretive work of Antoinc Lavoisier (1743-1794) to correctly understand this gas, Black's discovery eventually shattered the idea of a unified air. It also sent eighteenth-century pneumatic chemists on the fruitful journey of discovering many constituent gases in ordinary air. Later in the century, Joseph Priestley (1733 1804) became one of the dis¬coverers of dephlogisticated air, or oxygen. In several experiments, Priest¬ley noticed that a bird could not survive on the "spent" air left in a closed container after burning a candle to extinction. To his surprise, he found that a sprig of mint did not die. Rather, Priestley found that the plant grew without problems. He thought that the plant had somehow "purified" the air when he found it would again support a candle's (lame or the bird's respiration. Many scientists were confused by this finding, and most were unable to repro¬duce Priestley's experiments. This led to a heated scientific debate. (For more information, please see the entry on Carbon Dioxide and also the entry on Oxygen.)

Glossary

Photosynthesis. The term literally means "putting together with light." Photosynthesis is one of the most important chemical reactions in nature and the process by which plants make carbohydrates from carbon dioxide and water, given the presence of chlorophyll and light. Plants release oxygen as a by-product, which is essential for animal survival. Photosynthesis was first experimentally discovered by Jan Ingcnhousz in the early 1770s.

References

  1. Longrigg J. (1993) Greek Rational Medicine: Philosophy and Medicine from Alcmaeon to the Alexandrians. New York: Routledge.
  2. O'Malley CD. (1964) Andreas Vesalius of Brussels, 1514-1564. Berkeley: University of California Press.
    • Note: Considered the definitive biography. Renown historian of medicine, F. N. L. Poynter, stated of Dr. O'Malley's book: "What strikes me immediately on reading Professor O'Malley's monumental work is the coolness of its judgment, the absence of any kind of special pleading or even of that warmth of expression which comes from the biographer's identification with his subject. This almost Olympian detachment is rare indeed and not to be found in any of the outstanding examples of the biographer's art which readily spring to mind." (See F. N. L. POYNTER. 1964. Andreas Vesalius of Brussels — 1514-1564: A Brief Survey of Recent Work. Journal of the History of Medicine and Allied Sciences 1964 XIX(4):321-326. PMID 14215447
  3. xx
  4. Jonathan Shectman. (2003) Groundbreaking Scientific Experiments, Inventions and Discoveries of the 18th Century. Greenwood Press, Westport, CT. 2003.

Various codes

Excerpt from Plato's Phaedrus [1]
The Project Gutenberg Etext of Phaedrus, by Plato.

Socrates, in dialogue with Phaedrus, confirms the existence of Hippocrates the Asclepiad, indicating Hippocrates’ holistic approach to medicine, and implying that Hippocrates’ thought relating to medicine influenced philosophical thinking about such things as the nature of the soul:

SOCRATES: And do you think that you can know the nature of the soul intelligently without knowing the nature of the whole?
PHAEDRUS: Hippocrates the Asclepiad says that the nature even of the body can only be understood as a whole.
SOCRATES: Yes, friend, and he was right:--still, we ought not to be content with the name of Hippocrates, but to examine and see whether his argument agrees with his conception of nature.
PHAEDRUS: I agree.


Hormesis

Biologists often begin their explanation of the biological phenomenon of hormesis by citing the aphorism that what doesn’t kill you makes you stronger. The aphorism implies the existence of agents or activities potentially causing harm, but if insufficient to do so under the circumstances prevailing, actually confer benefit. A simple example: We know that habitually consuming a certain amount of food increases our chances for a long healthy life — a beneficial effect — but that habitually consuming food in certain larger amounts, all other things equal, can result in numerous deleterious physiological/biochemical manifestations of ill health, due to increasing the stores of body fat. Too much of a good thing turns it into a bad thing, so to speak. Thus the in-principle quantifiable biological phenomenon of ‘hormesis’ manifests itself.

In their 2008 New Scientist article entitled, “When a little poison is good for you”, hormetologists Mark Mattson and Edward Calabrese write this of the aphorism:

It describes the theory of hormesis - a process whereby organisms exposed to low levels of stress or toxins become more resistant to tougher challenges.  [2]

Biologists who specialize in the biochemical and physiological effects of toxic chemicals in living systems — toxicologists — use the term hormesis to refer to the effects of certain (often environmental) chemicals, having definite toxic effects when exposed to the system at certain known doses, yet having beneficial effects when exposed to the system at doses lower than those that cause toxicity. [3] They refer to the effect as “biphasic”: beneficial at 'low' doses, toxic at 'high' doses. Beneficial may mean only that the agent stimulates a biochemical or physiological phenomenon at low doses and inhibits it at high doses.

Hormesis does not manifest itself only in the circumstance of exposure to potentially toxic chemicals, as the example described above relating to gluttony illustrates. Any exposure or activity that tends to stress the living system’s prevailing physiological status can potentially elicit a hormetic biphasic response.[3] "Examples include many chemicals, temperature, radiation, exercise, energy intake and others." [3] Increasing the amount of physical activity by a more or less sedentary person, while it constitutes a stress on the cardiovascular and neuromuscular system long accustomed to relatively modest demands, may benefit the person’s general state of health. But an overenthusiastic convert to exercise may perform too much too quickly, resulting in injuries of many different kinds.

‘Hormetic’ biphasic dose-response effects occur commonly and appear as a general biological phenomenon among numerous animal species, non-gender- or age-specific, among microorganisms as well. The response parameters — the effects displaying hormetic biphasicity — include growth, longevity, metabolic phenomena, disease incidence, cognitive functions, and immune responses. Exercise, caloric restriction, ethanol, caffeine, various stress factors, and certain compounds in plants can also deliver hormetic responses, as can radiation exposure.ref name=mattsonns08/> [3] [4] [5] [6]

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  1. The Project Gutenberg Etext of Phaedrus, by Plato.
  2. Mattson M, Calabrese E. (2008) When a little poison is good for you. New Scientist 9 August 2008. pp. 34-39.
    • From the article: Mark Mattson is chief of the laboratory of Neurosciences at the US National Institute on Aging and a professor of neurosciences at John Hopkins University in Baltimore, Maryland. He is the most highly cited neuroscientist in the world. Edward Calabrese is a professor of toxicology at the University of Massachusetts in Amherst.
  3. 3.0 3.1 3.2 3.3 Mattson M. (2008) Hormesis defined. Ageing Res.Rev. 7:1-7. PMID 18162444.
    • Abstract: Hormesis is a term used by toxicologists to refer to a biphasic dose-response to an environmental agent characterized by a low dose stimulation or beneficial effect and a high dose inhibitory or toxic effect. In the fields of biology and medicine hormesis is defined as an adaptive response of cells and organisms to a moderate (usually intermittent) stress. Examples include ischemic preconditioning, exercise, dietary energy restriction and exposures to low doses of certain phytochemicals. Recent findings have elucidated the cellular signaling pathways and molecular mechanisms that mediate hormetic responses which typically involve enzymes such as kinases and deacetylases, and transcription factors such as Nrf-2 and NF-kappaB. As a result, cells increase their production of cytoprotective and restorative proteins including growth factors, phase 2 and antioxidant enzymes, and protein chaperones. A better understanding of hormesis mechanisms at the cellular and molecular levels is leading to and to novel approaches for the prevention and treatment of many different diseases.
  4. Calabrese EJ, Blain R. (2005) [http://dx.doi.org/10.1016/j.taap.2004.06.023 The occurrence of hormetic dose responses in the toxicological literature, the hormesis database: an overview. Toxicol. Appl. Pharmacol. 202:289-301. PMID 15667834.
    • Abstract: A relational retrieval database has been developed compiling toxicological studies assessing the occurrence of hormetic dose responses and their quantitative characteristics. This database permits an evaluation of these studies over numerous parameters, including study design and dose-response features and physical/chemical properties of the agents. The database contains approximately 5600 dose-response relationships satisfying evaluative criteria for hormesis across over approximately 900 agents from a broadly diversified spectrum of chemical classes and physical agents. The assessment reveals that hormetic dose-response relationships occur in males and females of numerous animal models in all principal age groups as well as across species displaying a broad range of differential susceptibilities to toxic agents. The biological models are extensive, including plants, viruses, bacteria, fungi, insects, fish, birds, rodents, and primates, including humans. The spectrum of endpoints displaying hormetic dose responses is also broad being inclusive of growth, longevity, numerous metabolic parameters, disease incidences (including cancer), various performance endpoints such as cognitive functions, immune responses among others. Quantitative features of the hormetic dose response reveal that the vast majority of cases display a maximum stimulatory response less than two-fold greater than the control while the width of the stimulatory response is typically less than 100-fold in dose range immediately contiguous with the toxicological NO(A)EL. The database also contains a quantitative evaluation component that differentiates among the various dose responses concerning the strength of the evidence supporting a hormetic conclusion based on study design features, magnitude of the stimulatory response, statistical significance, and reproducibility of findings.
  5. Calabrese EJ. (2008) Hormesis and medicine. Br. J Clin Pharmacol. PMID 18662293.
    • Abstract: Evidence is presented which supports the conclusion that the hormetic dose-response model is the most common and fundamental in the biological and biomedical sciences, being highly generalizable across biological model, endpoint measured and chemical class and physical agent. The paper provides a broad spectrum of applications of the hormesis concept for clinical medicine including anxiety, seizure, memory, stroke, cancer chemotherapy, dermatological processes such as hair growth, osteoporosis, ocular diseases, including retinal detachment, statin effects on cardiovascular function and tumour development, benign prostate enlargement, male sexual behaviours/dysfunctions, and prion diseases.
  6. Stumpf WE. (2006) The dose makes the medicine. Drug Discov. Today 11:550-5. PMID 16713907.
    • Abstract: Dose and time considerations in the development and use of a drug are important for assessing actions and side effects, as well as predictions of safety and toxicity. This article deals with epistemological aspects of dose selection by probing into the linguistic and cultural roots for the measure of medicine mediated by the medical doctor. Because toxicity is related to dose, historic and recent views suggest that less can be more. At low, medium and high dose levels, effects can differ not only quantitatively but also qualitatively. Dose-related target activation and recognition of enantiodromic thresholds between beneficial and toxic effects require elucidation of underlying events. Such studies, including hormesis and microdosing, call for extended ADME procedures with high-resolution methods in addition to the current low-resolution approaches. Improved information of drug logistics and target pharmacokinetics enables effective drug selection, dose determination and prediction. It also allows considerations of systems biology [i.e. integral (gestalt) pharmacology] exemplified by the drug homunculus, as in the case of vitamin D, that might lead to new paradigms and drug design.