Monthly Archives: January 2016

Breast milk protein could be used in fight against antibiotic resistance

An antibiotic developed from human breast milk could combat
certain drug-resistant bacteria, British scientists have found.

Tackling antibiotic-resistant bacteria, known as superbugs,
is a priority for the government. A panel set up by David Cameron forecast that
they would cost 10 million lives and £700bn a year worldwide by 2050 if the
problem went unchecked.

The breakthrough, by the National Physical Laboratory (NPL)
and University College London, found that the minuscule fragment, less than a
nanometre in width, is responsible for giving the protein its anti-microbial
properties.

This is what makes breast milk so important in protecting
infants from disease in their first months of life. The protein, called
lactoferrin, effectively kills bacteria, fungi and even viruses on contact.

After identifying the fragment, scientists re-engineered it
into a virus-like capsule that can recognise and target specific bacteria and
damage them on contact, but without affecting any surrounding human cells.

The team suggested this could help the fight against
antibiotic resistance by serving as “delivery vehicles” for cures. The capsules
could even pave the way for treatments for previously incurable conditions such
as sickle-cell disease, cystic fibrosis and Duchenne muscular dystrophy.

The Lactating Breast
When the baby sucks, a hormone called oxytoxin starts the milk flowing from the alveoli, through the ducts (milk canals) into the sacs (milk pools) behind the areola and finally into the baby’s mouth.
In an interview with the Times, Dame Sally Davies, the chief
medical officer for England, said governments and experts needed to do more to
tackle the antibiotics issue. “We need on average 10 new antibiotics every
decade. If others do not work with us, it’s not something we can sort on our
own,” she said. “This is a global problem. I am optimistic about this. The
science is crackable. It’s doable.”

Colin Garner, honorary professor of pharmacology at the
University of York and head of the charity Antibiotic Research UK, said the
situation was too urgent to wait for international consensus. “The pipeline of
new drugs had dried up and the problem was on the brink of becoming
intractable, he told the Times.

“My heart sinks when I hear the term ‘global initiative’.
How long has it taken the world to come to a sort of consensus about climate
change?” he said.

“The problem of antibiotic resistance will be at least as
intractable, because each nation takes a different view of what is required.”

The NPL findings are reported in the Royal Society of
Chemistry journal Chemical Science.

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Carbon emissions ‘postpone ice age’

The next ice age may have been delayed by over 50,000 years
because of the greenhouse gases put in the atmosphere by humans, scientists in
Germany say.

They analysed the trigger conditions for a glaciation, like
the one that gripped Earth over 12,000 years ago.

The shape of the planet’s orbit around the Sun would be
conducive now, they find, but the amount of carbon dioxide currently in the air
is far too high.

Earth is set for a prolonged warm phase, they tell the
journal Nature.

“In theory, the next ice age could be even further into
the future, but there is no real practical importance in discussing whether it
starts in 50,000 or 100,000 years from now,” Andrey Ganopolski from the
Potsdam Institute for Climate Impact Research said.

“The important thing is that it is an illustration that
we have a geological power now. We can change the natural sequence of events
for tens of thousands of years,” he told BBC News.

The Earth seen from space
Earth has been through a cycle of ice ages and warm periods
over the past 2.5 million years, referred to as the Quaternary Period.

This has seen ice sheets come and go. At its maximum extent,
the last glaciation witnessed a big freeze spread over much of North America,
northern Europe, Russia and Asia.

In the south, a vast expanse of what are now Chile and
Argentina were also iced up.

A fundamental parameter determining what dips Earth into an
ice age is the changing nature of its orbit around the Sun.

The passage around the star is not a perfect circle and over
time our planet’s axis of rotation also rocks back and forth.

These movements alter the amount of solar radiation falling
on the Earth’s surface, and if a critical threshold is reached in mid latitudes
in the Northern Hemisphere then a glaciation can be initiated.

Dr Ganopolski colleagues confirm this in their modelling but
show also the role played by the concentration of greenhouse gases in the
atmosphere.

And one of their findings is that Earth probably missed the
inception by only a narrow margin a few hundred years ago, just before the
industrial revolution took hold.

“We are now in a period when our (northern) summer is
furthest from the Sun,” the Potsdam researcher explained.

“Under normal circumstances, the interglacial would be
terminated, and a new ice age would start. So, in principle, we are in the
perfect conditions from an astronomical point of view. If we had a CO2
concentration of 240 parts per million (200 years ago) then an ice age could
start, but luckily we had a concentration that was higher, 280ppm.” Today,
industrial society has taken that concentration to over 400ppm.

The team says that an interglacial climate would probably
have been sustained anyway for at least 20,000 years, and, very probably, for
50,000 years, even if CO2 had stayed at its eighteenth century level.

But the almost 500 gigatonnes of carbon that has been
released since the Industrial Revolution means we will likely miss the next
best astronomical entry point into a glaciation, and with a further 500
gigatonnes of emissions the “probability of glacial inception during the
next 100,000 years is notably reduced”, the scientists say in their Nature
paper.

Add a further 500 Gt C on top of that and the next ice age
is virtually guaranteed to be delayed beyond the next 100,000 years.

Commenting on the study, Prof Eric Wolff from the University
of Cambridge, UK, said: “There have been previous papers suggesting that
the next ice age is many tens of thousands of years away, and that the
combination of seasonal solar energy at the latitude where an ice sheet would
form, plus CO2, is what determines the onset of an ice age. But this paper goes
much further towards quantifying where the limits are.

“It represents a nice confirmation that there is a
relatively simple way of estimating the combination of insolation and CO2 to
start an ice age,” he told the Science Media Centre.

And Prof Chris Rapley, from University College London,
added: “This is an interesting result that provides further evidence that
we have entered a new geological [Epoch] – ‘The Anthropocene’ – in which human
actions are affecting the very metabolism of the planet.”

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On this day in history – Alchemy was forbidden

In 1404, English alchemists were forbidden to use their
knowledge to create precious metals. Since the time of Roger Bacon, it had
fascinated the imagination of many ardent men in England. During the reign of
Henry IV, the Act of Multipliers was passed by the Parliament, declaring the
use of transmutation to “multiply” gold and silver to be felony. Great alarm
was felt at that time lest any alchemist should succeed in his projects, and
perhaps bring ruin upon the state, by furnishing boundless wealth to some
designing tyrant, who would make use of it to enslave his country. In 1689,
Robert Boyle lobbied for repeal of the Act.

The world’s largest gold bar, by PHGCOM (Own work by uploader, Toi Mine) [CC BY-SA 3.0 (http://ift.tt/HKkdTz) or GFDL (http://ift.tt/KbUOlc)%5D, via Wikimedia Commons

What is Alchemy?

Alchemy is a philosophical and protoscientific tradition
practiced throughout Egypt and Eurasia which aimed to purify, mature, and
perfect certain objects. Common aims were chrysopoeia, the transmutation of
“base metals” (e.g. lead) into “noble” ones (particularly
gold); the creation of an elixir of immortality; the creation of panaceas able
to cure any disease; and the development of an alkahest, a universal
solvent. The perfection of the human body and soul was thought to permit or
result from the alchemical magnum opus and, in the Hellenistic and western
tradition, the achievement of gnosis.  In
Europe, the creation of a philosopher’s stone was variously connected with all
of these projects.

In English, the term is often limited to descriptions of
European alchemy, but similar practices existed in the Far East, the Indian
subcontinent, and the Muslim world. In Europe, following the 12th-century
Renaissance produced by the translation of Arabic works on science and the
Recovery of Aristotle, alchemists played a significant role in early modern
science (particularly chemistry and medicine). Islamic and European alchemists
developed a structure of basic laboratory techniques, theory, terminology, and
experimental method, some of which are still in use today. However, they
continued antiquity’s belief in four elements and guarded their work in secrecy
including cyphers and cryptic symbolism. Their work was guided by Hermetic
principles related to magic, mythology, and religion.

Modern discussions of alchemy are generally split into an
examination of its exoteric practical applications and its esoteric spiritual
aspects, despite the arguments of scholars like Homyard and von Franz that they
should be understood as complementary. The former is pursued by historians of
the physical sciences who examine the subject in terms of protochemistry,
medicine, and charlatanism. The latter interests historians of esotericism,
psychologists, and some philosophers and spiritualists. The subject has also
made an ongoing impact on literature and the arts. Despite this split, which
von Franz believes has existed since the Western traditions’ origin in a mix of
Greek philosophy was mixed with Egyptian and Mesopotamian technology, numerous
sources have stressed an integration of esoteric and exoteric approaches to
alchemy as far back as Bolus of Mendes’s 3rd-century bc On Physical and
Mystical Matters (Greek: Physika kai Mystika).

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Enough oxygen on Earth long before animals rose

Oxygen is crucial for the existence of animals on Earth. But, an increase in oxygen did not apparently lead to the rise of the first animals. New research shows that 1.4 billion years ago there was enough oxygen for animals – and yet over 800 million years went by before the first animals appeared on Earth.

The Earth seen from Apollo 17 by NASA/Apollo 17 crew; taken by either Harrison Schmitt or Ron Evans 
Animals evolved by about 600 million years ago, which was late in Earth’s history. The late evolution of animals, and the fact that oxygen is central for animal respiration, has led to the widely promoted idea that animal evolution corresponded with a late a rise in atmospheric oxygen concentrations.

“But sufficient oxygen in itself does not seem to be enough for animals to rise. This is indicated by our studies,” say postdoc Emma Hammarlund and Professor Don Canfield, Nordic Center for Earth Evolution, University of Southern Denmark.

Together with colleagues from the China National Petroleum Corporation and the University of Copenhagen, Hammarlund and Canfield have analyzed sediment samples from the Xiamaling Formation in China. Their analyses reveal that a deep ocean 1.4 billion years ago contained at least 4% of modern oxygen concentrations.

The new study is published in the journal Proceedings of National Academy of Sciences.

Usually it is very difficult to precisely determine past oxygen concentrations. The new study, however, combines several approaches to break new ground in understanding oxygen concentrations 1.4 billion years ago.

The study uses trace metal distributions to show that the bottom waters where the Xiamaling Formation sediments deposited contain oxygen. The distribution of biomarkers, molecules derived from ancient organisms, demonstrate that waters of intermediate depth contain no oxygen. Therefore, the Xiamaling Formation deposited in an ancient oxygen-minimum zone, similar to (but also different) from those found off the present coasts of Chile and Peru.

With this backdrop, the researchers used a simple ocean model to estimate the minimum concentrations to atmospheric oxygen required to reproduce the distribution of water-column oxygen in the Xiamaling Formation.

“The water column had an oxygen concentration at least 4 % of present atmospheric levels (PAL). That should be sufficient for animals to exist and evolve,” says Canfield.

“Having determined the lowest concentration of oxygen in the air almost one and a half billion years ago is unique,” says Hammarlund, adding:

“Researchers know of simple animals, such as sponges and worms, that today are capable of managing with less than 4% PAL, even much less.”

“Sponges probably resemble some of the first animals on Earth. If they manage with less than 4 % today’s oxygen levels, it is likely that the first animals could do with these concentrations or less,” says Canfield.

The results differ from other studies and raise several questions, such as: Why then did animals rise so late in Earth’s history?

“The sudden diversification of animals probably was a result of many factors. Maybe the oxygen rise had less to do with the animal revolution than we previously assumed,” says Hammarlund.

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