CAS renders S&T support to the Beijing Olympics
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BCAS Vol.22 No.3 2008
Engineering
CAS renders S&T support to the Beijing Olympics
W
ith support from the
Chinese government,
CAS researchers strive
to make S&T contributions to the
2008 Olympic Games in Beijing. The
followings are some examples.
lHigh-quality purification system of
potable water for the Olympic Village
Developed by researchers with
the CAS Research Center for Eco-
environmental Sciences, the system
is capable of carrying out advanced
treatment of water in various
qualities, meeting the requirements
for clean and potable water at the
Olympic Village and other venues,
and enabling the residents to drink system for satellites developed by improve their performance. It brings
the water straight from the tap. researchers with the CAS Institute two transformations to the athlete-
of Computing Technology, has been training methods: one is to change
lKey technologies and emergency used for the data processing of the the traditional practice of a coach’s
measures for forecasting abnormal Beijing-1, an earth-observation observation with naked eyes to the
weather events in the Summer of micro-satellite specially designed the high-precision measurement and
Beijing 2008 Beijing Olympic Games. BWFS analysis of the human movements,
Developed by researchers from is a high-performance cluster system and the other is to transform the
the CAS Institute of Atmospheric for data transmission and sharing in a empirical method of evaluating an
Physics, the weather-monitoring system for massive data process in a athlete’s performance to the scientific
s y s te m is b a s ed on truckborne cluster environment. analysis of the human movements
Doppler weather radars and MODIS based on computer simulation.
satellite receivers. Based on a short- lDigital and 3-D computer
term weather-modeling system, it simulation of athlete’s movements l Design technology of the fire-
is used for real-time forecasting of Developed by the CAS Institute protection system for Olympic venues
rainstorms and thunderstorms in the of Computing Technology, the system Developed by the State Key
vicinity of Beijing. employs technologies in digital and Laboratory for Fire Sciences,
3-D computer simulation and the the University of Science and
lMass data storage technology computer-aided software for training Technology of China, the system
Blue Whale File System in sport items such as diving and introduces methods for fire risk
(BWFS)an integrated data storage trampoline, so as to help athletes to evaluation and performance-based
130 Bulletin of the Chinese Academy of Sciences
Vol.22 No.3 2008 WATCH
designing methods at Olympic system. By putting together the antijamming. It has been applied in
venues. It has also established a received data, the system serves as a the daily shot-putters training.
system for fire detection by image- platform of the data integration in a
processing and automatic orientating bid to serve the Olympiad organizing lLaser display technology
fire extinguishing monitoring, as well committee in scheming, decision- Developed by the CAS Academy
as an emergency management and making and managing. of Opto-electronics and by Phoebus
decision-making system in response Vision Co, a laser-based super-
to an unexpected event. lThe comprehensive sports training large screen has been used by main
system operation center of Beijing Olympic
lA dynamic environment monitoring Developed by researchers at the Building.
system via remote-sensing CAS Institute of Intelligent Machines,
Developed by CAS Institute the integrated system covers various lA solar-heat pump hot water demo
of Remote Sensing Applications, state-of-the-art training facilities system for the Olympic Village and
the system has used to make ranging from digital shot devices to Venues
dynamic monitoring on construction exercising apparatus for fencing. A Developed by researcher from
of Olympic facilities and their digital shot sensor to measure shot- the CAS Guangzhou Institute of
surrounding environment, transport, put force in time is introduced, which Energy Conversion, the system could
pollutants by using multi-phase has the same mass and external offer year-round hot water supply
and high-resolution telemetric data dimensions with the normal shot put. with solar energy supplemented by
supported by a global positioning Through calibrating experiments, the thermal pumps. it is the largest solar-
system, a geographical information sensor has good linearity and high powered air conditioning-heat pump
system (GIS) and a virtual simulation accuracy, work reliability and better system in China.
Facial recognition technology safeguards
Beijing Olympics
T
o ensure the safety of people who went through some
spectators and athletes at the 100 entrances equipped with facial
biggest-ever Olympic Games recognition surveillance machines
being held in Beijing, automation “Authenmetric” before they entered
experts from CAS have developed the National Stadium, known as the
China’s first system to identify Bird’s Nest, to enjoy the spectacular
individuals by their facial features, ceremony.
and successfully applied it to the Just like fingerprints, everyone’s
opening night security check on 8 face is unique. According to the
August. science of biometrics, the human
The first time such technology face has hundreds of “landmarks” on
was adopted as safety measures in it. These landmarks are distributed
the Olympic history, it identified more densely around the golden
and verified more than 80 thousand triangle of the eyes, nose and mouth.
Bulletin of the Chinese Academy of Sciences 131
BCAS Vol.22 No.3 2008
Research (CBSR), CAS Institute It can also adapt to inconsistent light
of Automation, spent more than conditions and different statures.
one year designing and working In fact, security experts already
out the system, a high-performance consider this novel technology the
innovation which combines cutting- most natural, visualized and highly-
edge facial recognition technology potential biometric identification
with radio frequency identification method to become popular soon on
card technology. important occasions such as major
Under the real-name registration sports games, conferences, exams and
The computer captures a person’s policy, ticket holders of the Beijing places like airports which see mass of
facial image(s), and analyzes the 2008 opening and closing ceremonies people ebb and flow.
details of the landmarks and distances were required to submit their personal Prof. Li was trained in the UK
and angles between them. This information and photos in advance. and worked at Microsoft Research
information is put into a database Then these images are analyzed, before entering the CAS institute. He
which can contain information about recorded in detail, and put into the now runs the world’s largest team for
millions of faces. When the person is database. When the audiences pass biometrics.
caught on camera again, the computer security checkpoints one by one, their The system was co-built,
searches the database until it finds the faces will be checked against and under the leadership of CBSR, by
best match. identified by the database. Authenmetric Co. Ltd., Beijing
Prof. LI Ziqing (Stan Z. LI) “Facial recognition is very Aerospace Changfeng Co. Ltd.,
and colleagues with the Center natural. It is what we have been Beijing Municipal Public Security
for Biometrics and Security doing since our birth,” Li explains. Bureau, etc.
Engineering Technology
An on-line gasoline blending system
put into production
A
new system for online research team from CASIA has
gasoline blending, been conducting research into the
which was developed system for five years. Because the
by researchers from the CAS new system enables the property
Institute of Automation (CASIA), parameters of a petrol product
has been put into production at precisely tunable and makes artificial
China Petrochemical Corporation mixture of the petrol products a 100%
(SINOPEC) and PetroChina success, the new system is hailed as a
Corporation. The new system is solution to the long-standing problem to the direct annual revenue as high
expected to thoroughly renovate the facing China’s oil refining industry. as 20 million yuan. If the system is
technology in this regard and achieve By introducing the new system, adopted by the 50 or so refineries across
maximal economic benefits in oil the Daqing Petroleum & Chemical Co. this country, according to experts, the
production stage. Ltd has succeeded in mixing gasoline annual direct economic benefits will
Headed by Prof. LI Zefei, a products up to 1.2 million tons, leading reach several billion yuan.
132 Bulletin of the Chinese Academy of Sciences
Vol.22 No.3 2008 WATCH
Basic Sciences
BAL Quasars without intrinsic X-ray absorption
W
hile observing a sample telescopes. Short for “QUASi- Scientists have come to a consensus
of quasars with broad stellAR radio source,” a quasar gives that quasars are active galaxies, or
absorption line (BAL) strong emissions of electromagnetic young galaxies still in their formative
in their spectra, Prof. WANG Junxian energy, including radio waves and era, each with a supermassive black
and his colleagues Prof. WANG visible light. Judged from the high hole at the center. The central black
Tinggui and Dr. ZHOU Hongyan with redshift in their spectra, this kind of hole feeds on a large amount of
the Center for Astrophysics dust and stars, releasing
at the University of Science enormous gravitational
Credits: ESA (Image by C. Carreau)
and Technology of China energy in the form of
(USTC) discovered that strong electromagnetic
unlike most of BAL radiation when collapsing
quasars, two of the observed into the bottomless black
do not show intrinsic X-ray hole.
absorption, indicating a Interestingly, while
different composition of voraciously devouring
matter in their outflows. mat t er, s ome q u a s a r s
This might help us better a l s o d i s c h a rg e g a s e s
understand how black into the space in
holes devour and project certain directions. The
gases, according to the An artist’s rendering of the BAL quasar with polar outflows. wide absorption lines
astronomers. appearing in their spectra
The sampled quasars keep celestial bodies is estimated to be are actually the imprints of these
throwing gases into the space along extremely far away from the Earth. gases, which absorb some light
their polar axes, instead of equatorial Most quasars are farther than three of certain wavelengths and hence
direction as most of their counterparts billion light-years, and the farthest leaving shadows on the otherwise
do, as revealed by previous known to date is around 28 trillion continuous spectra. It was previously
observations conducted by the same light-years away. This unimaginable believed that BAL quasars eject the
group of astronomers. Once again distance means that they could work gases along the equatorial direction,
the new data obtained from the same as emissaries from the early evolution parallel to their accretion discs,
objects surprised the astronomers, of our cosmos, bringing us precious which are formed by the matter
because strong X-ray absorption is clues about the aftermath of the Big continuously dropping into the
widely believed to be among the most Bang, which is hypothesized as the nucleus of the growing galaxy, the
prominent characteristics of most origin of our universe. supermassive black hole. The USTC
BAL quasars. A fascinating property of quasars group, however, identified a special
Quasars have been intriguing is the enormous amount of matter kind of quasars two years ago, which
objects of research for astronomers they draw from and throw back propel gases along their polar axes,
since the late 1950s, when the first into the universe, which gives them a direction perpendicular to their
of them were detected with radio the nickname of “cosmic engines.” accretion disk. Using XMM-Newton,
Bulletin of the Chinese Academy of Sciences 133
BCAS Vol.22 No.3 2008
a satellite administered by the When analyzing the snapshot than conceived, for example, a partial
European Space Agency, this group observations of four polar BAL covering of X-ray absorbing gases, and
made further observations on these quasars, the astronomers found that an extra contribution of X-ray to the
quasars during 2006 and 2007, trying two of the radiation sources could be spectra due to possible emission of this
to make clear whether these eccentric detected in X-ray. The spectral model kind of radiation.
celestial bodies absorb X-rays, as fittings indicated that these objects were The outflows from the black hole
most BAL quasars do. X-ray normal, suggesting that X-ray interest astrophysicists because they
To their surprise, the latest data shielding gas, like neutral gases, might might create disturbance in the host
suggest that these polar BAL quasars be absent in their outflows. According galaxy, and moreover, might prevent
are almost “transparent” to X-rays, to the authors, this could also imply that new stars from forming. This new
as they do not appear to make strong the nature of polar outflows is possibly discovery could help researchers
absorption of X-rays. This implies different from that of equatorial improve their computer simulation
that these polar BAL quasars might outflows, and polar BAL quasars might of the dynamic activity of quasars,
eject gases in a way more complicated occur at larger distances than their hence better understanding how these
than expected, as reported by the equatorial peers. The data obtained mysterious celestial bodies devour
astronomers in their paper published so far, however, are not sufficient to and eject gases, and through which
in the April issue of The Astrophysical rule out alternative reasons, including influence the evolution of the host
Journal Letters of USA. an absorption mode more complex galaxies.
Engineering
First engineering application of a 4,000 m
ocean floor survey successful
D
TA - 4 0 0 0 , a d e e p -
tow acoustic system
jointly developed by
researchers from the CAS Institute of
Acoustics and their co-workers, has
accomplished the task of examining
an international submarine cable
route in the northern part of South
China Sea in last February. The
system worked stably for 145 hours
undersea, checking the cable for 640
km with plenty of reliable data. overcame many key research and meters undersea.
Based on previous research design problems, such as a deep The DTA-4000 deep-tow acoustic
results of the researchers, the novel withstanding-voltage sonar array, a system could realize the definite goal
system innovatively put forward a deep-sea high-stability tow platform to search and facilitate large devices
new signal processing method, which and a high-performance and low- to work. The system has a promising
could get high-resolution images power mini-sonar electric system. future in marine resources exploration
about benthonic terrain. The system Moreover, it could run below 4,000 and marine engineering.
134 Bulletin of the Chinese Academy of SciencesVol.22 No.3 2008 WATCH
Environment and Resources
Unravel the mystery of musical dripstones
H
it with a rubber mallet,
a group of 12 stalactites
(popularly known as
dripstones), in the Kongshan Cave,
central China’s Hubei Province
can amazingly produce various
notes and complete melodies like
ancient musical bells and chime
stones. A three-day investigation of
CAS karstologist LIU Zaihua and
colleagues in early May sheds light
on the mystery.
On-the-spot experiments and
analyses show that the interesting
Semi-annular in shape, the Kongshan Cave has a long history dating back to the
phenomenon is due to a combination Qing Dynasty. It is 1,584 m long, 48 m to the highest and 26 m to the widest with
of causes, such as the chemical wonderful natural landscapes, including petrified bouquets, stalagmites, pedestal
rocks and curtains. The Cave was opened to the public in 1986.
composition, structure and size of
the stalactites, as well as external Cave stalactites became known as is of 1.5 to 4 cm. These differences are
factors like weathering enhanced by “stone bianzhong" among musicians key factors for the stalactites to sound
lighting, says Prof. Liu with the CAS- and tourists. various notes and pitches.
affiliated State Key Laboratory of The dripstones are largely made Meanwhile, dry sediments are
Environmental Geochemistry. up of calcite, a common and stable observed around the roots of the
When these dripstones were mineral chemically known as calcium stalactites, making their sounds unique.
first discovered to have an amazing carbonate (CaCO 3), also the basic The professor explains that before the
effects of musical instrument in constituent of limestone and chalk. Kongshan Cave was opened to the
August, 2007, experts found that The internal structure consists of public as a tourist site, the stalactites
each of the miraculous stalactites, concentric rings around a hollow had a wet surface; but with high-
within a distance of four meters, was channel from inside, Liu says. These intensity lighting over recent years,
able to give two to three different are basic elements for the stalactites the water is gradually evaporated from
notes featuring low but powerful to produce musical notes. outside the stones. While a wet surface
qualities, which strictly go with the Secondly, seven of the entire 12 may lead to high and clear tones, a
modern heptatonic scale and twelve- dripstones, as especially suitable for stalactite with a dry coat produces
tone equal temperament. Resembling music performance, are of great variety rather low and powerful sounds.
the huge bronze bells hung on in shape, length and diameter. Each Still, the geographical location
wooden racks (“bianzhong”) that cone is of a length between 1.5 and 2.5 is critical for these musical tones.
ancient Chinese played on important m, with a broken top from 0.1 to 0.4 m. According to Liu, they grow under a
occasions like religious ceremonies Each has a diameter ranging from 8 to soundly ventilated condition, which
and imperial audiences, Kongshan 30 cm, where its internal channel width is conducive to the exchange of
Bulletin of the Chinese Academy of Sciences 135BCAS Vol.22 No.3 2008
air, water and carbon dioxide. The The scientists give suggestions also deputy director of the Karst
weathering mantle of each dripstone, to the protection and maintenance of Dynamics Laboratory affiliated to
with a thickness between 0.5 and 1 the marvelous natural instruments. the Ministry of Land and Resources.
cm, also contributes to its unique People need to take better control As a PhD in hydrochemistry from
tone color. Besides, the narrow over the stability and weathering China University of Geosciences as
space in cave enhances the echo and speed of the stalactites. They also well as in karstology from Bremen
penetration of music. should reduce the frequency of strikes University, Germany in the 1990s, he
With above explanations, the and the intensity of lights, and restrict worked as a postdoc in Germany from
mystery of musical stalactites at the the number of visitors for the sake of 1999 to 2000. His research interests
Cave has been generally unmasked. carbon dioxide control. lie in the evolution of hydrochemistry
The group has collected samples Prof. Liu is currently a in karst areas, the mechanisms
for further studies. For instance, they research professor with the State of karst kinetics, etc. He also co-
will apply the uranium dating method Key Laboratory of Environmental authored with CAS academician
to work out the date when these G e o c h e m i s t r y, C A S G u i y a n g YUAN Daoxian on a UN-sponsored
stones came into being. Institute of Geochemistry. He is report on global karst correlation.
Life Sciences
Active compounds in bitter melon
might treat diabetes
I
t seems like your mum was right. compounds' structures and absolute
A study led by YE Yang with the configurations. They tested these
CAS Institute of Meteria Medica compounds in vitro on muscle and
in Shanghai, China and David Ernest fat cells, and found four compounds
James at the University of New South that could stimulate an increase in
Wales in Sydney has shown that glucose entry into cells by a factor
eating bitter melons really is good for of three to four — comparable to
you. the optimum response achieved by
The bitter melon (Momordica insulin. Further study revealed that
charantia) is an ingredient often these compounds activate AMPK,
used in Chinese cooking, and this the protein responsible for regulating
unique bitter-tasting fruit is slowly hypoglycaemic effects on humans, fuel metabolism and enabling glucose
being introduced in the West. For which can serve as a treatment uptake — processes that are impaired
thousands of years, traditional for Type 2 diabetes, but until now in diabetics.
Chinese medicine has been using the precise active compounds Of these four compounds, the
the ‘neutral and extremely cooling’ responsible for these effects have not researchers tested two in vivo on mice
bitter melon as a medicinal herb been clearly identified. fed on a high-fat-content diet. They
to treat different types of ‘heat Ye, the researchers have extracted found a significant improvement
fatigue.’ Several clinical studies a number of compounds from in the glucose tolerance in these
have shown that bitter melons exert bitter melon and determined these animals. (Source: Nature China)
136 Bulletin of the Chinese Academy of SciencesVol.22 No.3 2008 WATCH
Environment and Resources
The sixth “golden spike” in China
A
taskforce led by Prof. Geologists use chronostratigraphic of global stratigraphic division and
PENG Shanchi with the units (eonothem, erathem, system, correlation. The selection of a GSSP
CAS Nanjing Institute of series and stage) to help correlate section in a certain county is regarded
Geology and Palaeontology (NIGP) rock sequences. Over the past 150 as an honor of the host country and a
has persuaded the international hallmark to showcase the country's
geological community that the stratigraphic study level. So far, six
stratotype for the base of Cambrian "golden spikes" have been defined
stage 7 about 503 million years in China. The other five are:
ago is located in central China’s In 1997, the Huangnitang
Hunan Province. cross-section in Changshan
On 30 March, Dr. Peter T. County of Zhejiang Province was
Bobrovsky, secretary-general designated as GSSP for the base of
of the International Union of Darriwillian Stage of the Middle
Geological Sciences (IUGS), Ordovician Series, becoming the
ratified the Global Standard- first "golden spike" in China.
stratotype Section and Points Located in the Meishan
(GSSP) for that base is named Section, Changxing County in
Guzhangian. Beforehand, the Zhejiang, the second of such spike
proposal had been accepted by a in China is set up for the boundary
unanimous vote at meetings of between Permian and Triassic
Exposure of the GSSP for the base of Guzhangian.
the International Commission on Systems. It was ratified in 2000.
Stratigrahy and the Sub-commission years, they have mainly relied The GSSP for the base of the
on Cambrian Stratigraphy. on significant events, such as the Paibian Stage and the Furongian
The position of this GSSP appearance of a specific fossil, or a Series in the Huaqiao Formation,
(popularly known as a “golden reversal in the planet's magnetic field, Paibi section, Hunan Province, is the
spike”) is 121.3 meters above the to define the boundary between two third golden spike in this country.
base of the Huaqiao Formation, at time periods. Having defined these Ratified in 2003, it is the first formal
a horizon coinciding with the first physical boundaries, researchers Stage and the first formal Series
appearance of the cosmopolitan then attempted to correlate and date within the Cambrian System.
agnostoid trilobite Lejopyge them. But geologists in different parts The fourth is the GSSP for the
laevigata. It is another “golden of the world used different rocks as base of the Wuchiapingian Stage
spike” defined by Prof. Peng and his benchmarks, leading to disagreements in Lopingian Series of the Permian
colleagues in the Cambrian period. over the exact definition of each System which was formally ratified
The GSSP for the base of the Paibian period. on 3 September, 2005.
Stage and the Furongian Series in the Commonly known as the The fifth one is GSSP for the
Huaqiao Formation, Paibi section, "golden spike" in chronostratigraphic base of the Changshingian Stage in
Hunan Province, was ratified in 2003 research, GSSP provides a common the Lopingian Series of the Permian
as the first formal Stage and the first language for geoscientists speak to System which was ratified on the same
formal Series within the system. one another. It is the only standard date as the Lopingian-base GSSP.
Bulletin of the Chinese Academy of Sciences 137BCAS Vol.22 No.3 2008
Life Sciences
Genome of a mosquito-killing bacterium decoded
R
esearchers with the CAS effects of the pesticides to both 0
Wuhan Institute of Virology humankind and the environment,
4Mb
(WHIOV) recently mosquito control using the insect-
completed the genome sequencing of attacking bacteria Bacillus sphaericus
1Mb
a mosquitocidal bacterium Bacillus and Bacillus thuringiensis subsp.
sphaericus C3-41. The feat, first of its israelensis has been accepted across
kind in China, is expected to further the world.
promote the bio-control studies of Bacillus sphaericus strain C3-41, 3Mb
mosquitoes. selected by WHIOV researchers, is an
aerobic, mesophilic, spore-forming
2Mb
The mosquito transmits some of
the world’s most serious vector-borne microorganism that has been used C3-41, and compared the data with
diseases, such as malaria, encephalitis, with great success in mosquito control that of other published sequences of
filariasis, yellow fever, and dengue. programs over the past two decades. entomopathogenic bacteria.
Vector control is recognized as an Teaming up with their co-workers Experts say that their knowledge
effective approach to controlling from the CAS Beijing Institute of will increases people’s understanding
the diseases. Due to the increasing Genomics and the Cardiff University of the bacilli and may offer prospects
resistance of the insect to chemical in UK, WHIOV researchers mapped for future genetic improvement of this
pesticides, as well as detrimental out the complete genome of the strain important biological control agent.
Chemistry
A new appraoch for identifying metabolic
biomakers
T
he idea of finding a single German chemists may just have clinical biomarker. Some researchers
metabolite biomarker that improved the chances of detecting a have got around this problem by
can unambiguously diagnose proper biomarker. monitoring changes in the abundance
a disease is a beguiling one, but The problem is not identifying of a whole suite of different biomarkers,
unfortunately not currently supported metabolites that differ between healthy rather than trying to pick out a single one.
by reality. Although researchers have subjects and disease sufferers, which The team of Chinese and German
reported the discovery of a whole can easily be revealed using high chemists led by XU Guowang from
range of potential biomarkers for performance liquid chromatography the CAS Dalian Institute of Chemical
numerous diseases, they often don't (HPLC), mass spectrometry (MS) and Physics, chose a different tack. They
stand up to closer scrutiny. But now, multivariate statistical techniques such decided to develop a novel strategy for
by combining together a whole range as principal components analysis, but working out the identity of differently-
of different analytical and statistical in determining which of these many expressed metabolites, as identifying a
techniques, a team of Chinese and metabolites are best able to act as a metabolite can help to reveal its origin
138 Bulletin of the Chinese Academy of SciencesVol.22 No.3 2008 WATCH
and functions. And this information — one which is able to distinguish metabolite, although it won't be able to
can indicate whether the metabolite between healthy controls and disease distinguish between different isomers.
will make a good biomarker, by sufferers — the chemists analyze To do this, the researchers compare
revealing whether it has a central role it with tandem MS. This technique the retention times of the candidate
in the disease process. fragments the metabolite into its isomers with the retention time of their
Their work was published product ions and therefore provides metabolite on both HPLC and gas
recently in Analytical Chemistry information on its molecular structure, chromatograph columns.
under the title of “Practical approach such as indicating whether it contains T h e r es ear ch er s t es t e d t h i s
for the identification and isomer carboxyl or amide groups. Next, Xu strategy on a metabolite in urine that
elucidation of biomarkers detected in a and his team analyze the metabolite they discovered could distinguish 28
metabonomic study for the discovery using Fourier transform ion cyclotron healthy controls from 23 individuals
of individuals at risk for diabetes by resonance mass spectrometry (FTICR- found to be insulin resistant, which is
integrating the chromatographic and MS), which can provide an accurate a condition that presages full-blown
mass spectrometric information.” measurement of the metabolite's diabetes. After conducting an FTICR-
The standard way of identifying mass and also reveal its elemental MS analysis of the metabolite, the
metabolites is to compare their spectral composition. researchers were able to obtain 18
data with that in metabolite databases Only after gathering this detailed possible matches from metabolite
such as the Human Metabolome information on mass and elemental databases. They then removed those
database, but this often fails to produce composition do the chemists molecules that didn't contain the
a firm match and also cannot identify interrogate metabolite databases, phenoxy and carboxyl groups that the
specific isomers. So Xu and his team thereby to ensure that the only ones tandem MS analysis had indicated
set about designing a completely novel come up with a fairly short list of formed part of the metabolite.
identification strategy, based on applying good matches. They then whittle This revealed that the metabolite
successive analytical and statistical these matches down still further by was one of three isomers of
techniques to metabolite spectra. removing those that don't fit with the hydroxyhippuric acid. Finally, by
After choosing an interesting structural information provided by comparing the retention times of
looking metabolite from the spectra the tandem MS analysis. Hopefully, these isomers, the researchers were
this process should reveal a single able to pinpoint the metabolite as
candidate for the identity of the 3-hydroxyhippuric acid.
Proving the advantage of this
technique, the successful identification
allowed the chemists to speculate
about the exact link between this
metabolite and insulin resistance. For
3-hydroxyhippuric acid is known
to form part of the pathway for
metabolising dietary flavonoids (plant
pigments). This pathway involves
the action of gut bacteria and recent
research has shown that the precise
composition of the bacteria in the gut
is associated with insulin resistance.
The scheme proposed by Prof. Xu and his co-workers succeeded for the first time in (Adopted from a news report at www.
qualitatively identifying metabolic markers through the correlating of the segmenting
behavior of mass spectrometry with the retention behavior of chromatography. separationsNOW.com)
Bulletin of the Chinese Academy of Sciences 139BCAS Vol.22 No.3 2008
Chemistry
A new bread improver to replace
traditional gluten fortifier
S
cientists with the CAS contain a certain content of water, a promote the dough’s toughness.
Changchun Institute for proper specific volume and an evenly However, recent studies show that the
Applied Chemistry recently distributed porosity. The conventional bromate is a carcinogen.
developed a new plant derivative practice widely accepted both at The new additive developed
of polysaccharide to replace the home and abroad is to put in a certain by CAS scientists is able to replace
traditional agent of gluten fortifier in amount of potassium bromate to the bromate in the bread and satisfy
the bread-baking industry. various requirements.
The new bread improver is a According to experts, the new
kind of high-purity sugar extracted ingredient is featured with a new
from a plant endemic to China. With special microstructure and when it is
a new molecular structure, it cannot mixed with flour, the polysaccharide
be digested by human body, thus will wrap the flour particles in
producing no toxicant side-effects. the dough, including the air drops
In order to bake mellow, soft contained in them. So the baked
and tasty bread, the flour dough must product is mellow, porous and tasty.
Life Sciences
Higher dopamine level promotes male-
male courtship in Drosophila
O
n May 21 2008, Journal fundamental to the propagation of be induced by gene mutation or
of Neuroscience published animal species and their adaptations ectopic gene expression.
an online paper from the to changes in the environment. Male Dopamine, as an important
Institute of Neuroscience, the CAS courtship in Drosophila is complex, neuromodulator, is involved in
Shanghai Institutes for Biological consisting of a stereotypic set of the regulation of many simple
Sciences, entitled "Increased behaviors, including orientation and complex behaviors. The role
dopamine level enhances male-male towards a female, tapping with of dopamine in sexual behavior
courtship in Drosophila." This work its forelegs, following the female, has been extensively studied in
was done by Mr. LIU Tong, a doctoral singing a courtship song, licking mammals. Some studies indicated
candidate, and colleagues under the the female's genital, attempting that the dopaminergic system plays
supervision of Dr. GUO Aike, and in copulation, and final copulation. a role in regulating the receptivity
collaboration with Dr. Jean-François While male flies generally court of female and sexual arousing of the
Ferveur from France. female flies, an intense male male in fruit fly courtship behavior.
Courtship behavior is homosexual courtship behavior can This current study showed that
140 Bulletin of the Chinese Academy of SciencesVol.22 No.3 2008 WATCH
elevation of dopamine level induced activity, or their general olfactory/ male courtship towards other mature
male-male courtship behavior in gustatory abilities. Furthermore, males. Although, at this moment,
fruit flies. In this study, genetic, visual and chemosensory inputs it is still unknown that how high-
pharmacological, behavioral and played a positive role in this level dopamine can induce male-
surgical methods were used to enhancement, indicating that male courtship behavior in fruit
show that male flies with increased the high intensity of male-male flies and whether these results can
dopamine level tend to have interactions shown by males with be generalized to other species,
enhanced propensities to court other higher dopamine levels is related to further dissections of fly male-male
males, without affecting overall their altered sensory perception of courtship may help us understand the
male heterosexual courtship, their other males. These findings indicate fine mechanisms underlying sensory
attractiveness to other males, their that increased dopamine level is communication regulating inter-
short-term spontaneous locomotor correlated with a more intense male- individual behaviors.
Resources and Environment
Minqin, once an oasis, initiates research
to curb desertification
E
v e r y d a y, C H A I E r h o n g
drives a motorcycle miles
away to fetch water and
irrigates his cotton fields. Though the
water is salty and the cotton is low-
yielding, they are two most important
things for Huang’s living. Some of his
neighbors, pushed out by the drifting
sands and water shortages, have left
their homes in Minqin County to
resettle elsewhere.
To save Minqin from becoming a the CAS Cold and Arid Regions recent years have seen it worsen into
second Lop Nur, a pilot demonstration Environmental and Engineering one of China’s four major sources
research project is kicked off on Research Institute will take charge of sandstorms. On one hand, there
March 21, 2008 to address impending of the project with Prof. XIAO was a drive of land reclamation and
desertification and develop Honglang as chief scientist. reservoir construction along the
technologies for local rehabilitation. According to Prof. Xiao, Minqin Shiyang River, upstream from Minqin
As a National Key Technology R&D County, located in the northeast of County, and waters were diverted
Program, it is part of a 4.7-billion- Hexi Corridor on lower reaches of for irrigation purposes. On the other
yuan national project on integrated the Shiyang River, is bounded by hand, years of unprecedented dry
water resources management around Tengger and Badain Jaran Deserts in spells have brought Minqin very
the Shiyang River Basin. the east, west and north. The oasis in little annual precipitation. Today, the
Joining efforts from Gansu- Minqin was once a natural barrier on county is one of the driest places and
and Beijing-based research bodies, the path of the encroaching sand. But one of the most seriously affected by
Bulletin of the Chinese Academy of Sciences 141BCAS Vol.22 No.3 2008
desertification in China. at providing experience and sand-proofing, reforestation, rain-
Government leaders have technological supports for the fed restoration of desert vegetation,
vowed to protect the area. Premier mega-project on ecological and high-efficiency and water-saving
WEN Jiabao called for “unremitting environmental restoration along reconstruction of green oases,
efforts” to halt the invasion of sand Shiyang River, which is now under upstream water-source conservation
and promote the local sustainable preparation. Anyway, the anti- and an overall study on water-
development. He even ordered desertification effort in Minqin is a ecology-economy management in
provincial officials to supply more big part of the entire plan, and most the Basin.
water to the drought-stricken farmers urgent as well,” Xiao says. With a total investment of $5.7
by tapping on upstream reservoirs. Researchers will develop million, the work is planned to wind
“Our pilot research aims integrated technologies concerning up by 2011.
Life Sciences
Discovery of neural circuits for saccadic
modulation of visual perception
I
n daily life, we move our eyes Sciences under the CAS Institute
frequently to search for or fixate of Biophysics in Beijing recently
a target of interest with the retinal discovered the neural circuits that
fovea. Usually, the eyes would dart modulate visual responses of brain
from one position to another in the neurons around the saccades in the
visual field at velocities higher than pigeon, which might be critical for
500 degrees per second. This rapid interpreting the mysteries of visual
eye movement is called a saccade. perception.
From a physical point of view, As the visual pathways in the courses of these neurons in response
when our eyes make a rapid and pigeon are basically similar to those to saccades, the authors discovered
jerky movement, the image of an of mammals including human beings, the neural circuits for transmitting
object moves swiftly across the with a comparable ability for visual corollary discharge signals from the
retina, resulting in blurred and cognition, experts believe that this brainstem raphe complex through
unstable visual perception. In fact, discovery is of significance for the optokinetic nuclei to the visual
we can still perceive a stable and explaining how our brain processes thalamus as a relay station and finally
clear-cut world. Obviously, our visual information and modulates to telencephalic neurons.
brain makes a clever treatment of visual responses of cortical neurons Experts say that this finding
the contradiction between biology during saccades. is conductive to revealing the
and physics of visual perception. As recently reported online mystery of how visual information
However, little is known about by the prestigious journal Nature is processed in the brain and how
the neural mechanisms behind the -Neuroscience, the researchers we can perceive a stable and clear
natural ingenuity. examined saccadic responses in more visual world during saccades. In
A research team headed by Prof. than 300 neurons in five brain areas of addition, it might inspire scientists
WANG Shurong at the State Key a pigeon. After analyzing the change to design visual robots with eye
Laboratory for Brain and Cognitive in discharge frequencies and the time movements.
142 Bulletin of the Chinese Academy of SciencesVol.22 No.3 2008 FOCUS
Research progresses shed
light on superconductivity
mechanism
T
he spring of 2008 saw substantial breakthroughs with the crystalline lattice. Based on the understanding that
in superconductivity research. Four groups electrical resistivity results from the energy loss produced
of physicists, one after another, achieved when traveling electrons collide with the vibrations of
remarkable progresses in the study of iron-based materials the crystalline lattices or defects in the material, it argues
after the breakthrough made by H. Hosono’s group in that at extremely low temperatures, no sufficient energy is
Japan, providing renewed insights into the fundamental available to separate these pairs, making it impossible to
mechanism of high-temperature superconductivity (HTSC), deflect them. In other words, no electrical resistance can
a perplexing enigma on the frontier of condensed matter arise in this case. Nevertheless, it is widely doubted that
physics. this theory can explain the superconductivity of cuprate
materials, as the latter’s electrical resistance turns into
Enigma of high-temperature superconductivity zero at a critical transition temperature (Tc) as high as
Superconductivity, a fascinating quantum phenomenon over 138 kelvin (-135.15˚C), which makes available the
that occurs in certain materials at extremely low energy necessary for breaking the electron pairs (named
temperatures featuring the vanishing of electrical resistance Cooper pairs amongst the physics community). The limited
and interior magnetic field, has attracted intense attention materials available for theoretical exploration—the cuprate
from scientists. The discovery of HTSC in copper oxides, system had long been the only high-Tc superconductors
or cuprate in 1986 has fueled new waves of enthusiasm known by human society—made this mechanism even
for this topic and various cuprate high-temperature more mysterious. Against this background, the physicists
superconductors have been synthesized. For a long time, have long been awaiting a non-cuprate system of high-Tc
however, the underlying mechanism of HTSC remains superconducting materials to gain new inspirations.
elusive, though scientists have reached a greater agreement
on the mechanism of conventional superconductivity. Breaking through
So far, a well-known effort to explain this magical The latest confluence of discoveries of iron-based high-
effect in conventional superconductors is the BCS theory Tc superconductors by Japanese and Chinese scientists,
based on electron-phonon interaction coupling. This as well as the ensuing debate is fostering new hopes for
theory, which was developed by John Bardeen, Leon N. solving this predicament. Soon after the synthesis of the
Cooper and John R. Schrieffer in 1957 and reaped the 1972 lanthanum oxygen fluorine iron arsenide (LaO1-xFxFeAs),
Nobel Prize in Physics, suggests that the disappearance of a superconductor with a Tc of 26 kelvin (-247.15˚C) by a
electrical resistance is due to the formation of electron pairs Japanese group with the Tokyo Institute of Technology
at extremely low temperatures, through their interactions (TIT), three groups of researchers at the CAS Institute of
Bulletin of the Chinese Academy of Sciences 143BCAS Vol.22 No.3 2008
(a) (b) in so short a time, IoP Director-
By courtesy of Prof. Fang Zhong.
general Prof. WANG Yupeng, a
theorist specialized in condensed
matter physics, attributes this to the
academic build-up of his institute
over several decades on cuprate high-
Tc superconductors. “We benefit
from a powerful faculty, a very good
environment for research and lasting
support from the government which
helps scientists focus on important
Prof. Wang Nanlin's group works closely with a theoretical group led by Prof. Fang issues on the disciplinary frontiers.”
Zhong, and successfully identify a spin-density-wave (SDW) instability in undoped
LaOFeAs. They further suggest that the superconductivity competes with the
This institute is emerging as a world
SDW instability in pure LaOFeAs, and overcomes the latter when the samples are known center of scientific excellence
doped with fluorine. The existence of SDW in LaOFeAs is later demonstrated by the
neutron diffraction studies conducted by two independent groups from the USA. (a)
with a quite low annual budget of
The stripe-type antiferromagnetic pattern in the SDW state of LaOFeAs; (b) Nesting $25 million compared to those of
between electron and hole Fermi surfaces.
Western countries.
Physics (IoP) and one group at the University of Science Achieving high-temperature superconductivity
and Technology of China (USTC) reported, in succession, Truly, opportunities favor those who are well prepared.
their successes in inducing HTSC in different iron-based Prof. Wang Nanlin’s group has been engaged in growing
materials. single crystals of LaOFeAs since last December in a
The IoP gained first limelight when two of its research hope of investigating their electronic properties. Another
groups, respectively headed by Profs. WANG Nanlin IoP fellow, CAS Member Prof. ZHAO Zhongxian made
and WEN Haihu, confirmed the result obtained by the significant contributions to cuprate high-Tc superconductor
TIT group within one week after its publication. Then research as early as in 1987. Once again in this spring,
on 25 March, a USTC group headed by Prof. CHEN Zhao’s team scored “quick” and arresting achievements. On
Xianhui announced their successful identification of 28 March, his group reported a Tc of 52 kelvin (-221.15˚C)
superconductivity at a Tc of 43 kelvin (-230.15˚C) in the in a new superconductor, the praseodymium-arsenide
samarium oxygen fluorine iron arsenide (Sm1-xOxFxFeAs). compounds (PrO1-xFxFeAs). This was the first time ever a
Only one day later, Prof. Wang Nanlin’s group reported Tc above 50 kelvin to be achieved in a non-cuprate system,
another superconductor, the Ce(O1-xFx)FeAs, with a Tc of 41 suggesting the discovery of a new high-Tc superconductor.
kelvin. These two results, each independent from the other, Soon after that they reported another new system, the
mark a breakthrough, as the Tc went beyond 39 kelvin, the Nd[O 1-x F x ]FeAs with a Tc of 51.9 kelvin, explicitly
commonly assumed McMillan Limit and can be defined as confirming the potential of the quaternary iron-arsenide
unconventional superconductors. Subsequently, the later compounds as a new family of high-Tc superconducting
group also reported that the Tc could be further increased to materials. Again on 13 April, they further raised the Tc
almost 50 kelvin by substituting the element La with other to 55 kelvin (-218.15˚C) in Sm[O 1-xFx]FeAs by using a
smaller rare earth elements, for example, Nd. novel method—a high-pressure synthesis method, which
The seemingly surprising blossom of significant could make more fluorine doping to the oxygen site and
discoveries at IoP is actually not so accidental as it looks. get higher Tc. So far this remains the highest Tc achieved
When asked about what has made it possible for IoP to in all non-cuprate systems. Later in April, moreover,
respond so quickly and achieve so many breakthroughs they reported similar superconductivity in six lines of
144 Bulletin of the Chinese Academy of SciencesVol.22 No.3 2008 FOCUS
materials from the same quaternary family, depicted as “natural foe of superconductivity.” This anomaly is
ReFeAsO1-, where Re indicates rare earth elements Gd, especially interesting for theorists because of the implied
Sm, Nd, Pr, Ce or La. Rather than F-doping, in this work potential of greater discoveries.
the superconductivity is induced by oxygen-vacancies in
the crystal lattice, which they proved to be applicable to Working at theoretical frontier
all the six lines and actually more effective an approach. Particularly, the identification of the possible connection
The discovery of this general applicability is expected to between the spin-density-wave (SDW) instability and
facilitate later experiments and theoretical research in this the resistivity anomaly in a new system is deemed to be
direction by providing a much simpler studying platform. an encouraging effort to reveal the HTSC mechanism.
Naturally, the exceptionally high critical transition In cooperation with another IoP group led by Prof. Fang
temperatures achieved in this wave of discoveries have Zhong, Prof. Wang Nanlin’s group discerned that a phase,
gained due acclaims over the world. Although some of the antiferromagnetic SDW instability, was competing with
the compounds in the parent family of the new system superconductivity in the LaO1-xFxFeAs system. The two
were found to show superconductivity at extremely low groups demonstrated that this SDW instability might be
temperatures, for example between 3 to 5 kelvin, none responsible for the resistivity anomaly occurring at about
was ever found to undergo any superconductivity above 150 kelvin in undoped LaOFeAs. When the samples are
20 kelvin. What is more striking, however, is the fact that treated with F-doping, however, the instability is suppressed
HTSC could even be induced in iron-based compounds, and hence leading to the superconducting ground state.
which was widely believed to be a mission impossible They further show that similar competing orders exists in
because of the ferromagnetism of these materials, the other rare-earth substituted systems. The SDW instability in
the undoped compound was later confirmed by the neutron
diffraction studies conducted by two independent groups in
the USA. The surprisingly high Tc achieved by Wang’s group
By courtesy of Dr. Ren Zhi’an.
in CeOFeAs samples, as high as 41 kelvin, has suggested
intriguing prospects implied in the competing phenomenon.
In fact, being consistent with this work, Prof. Zhao’s group
has proved that producing oxygen vacancies in the system
is more efficient an approach than F-doping to inducing
superconductivity in this kind of materials and higher Tc has
been achieved. It is believed that this discovery will inspire
further pursuit of the fundamental mechanism of HTSC.
On the other hand, the discovery made by Prof. Wen’s
group also attracts extra attention, as it directly challenged
the latest hypothesis proposed by the TIT group led by
chemist Hideo Hosono. The TIT group explicitly stated
in February in their paper that a critical factor for the
occurrence of superconductivity in the new system of
superconductors was electron doping, rather than hole
doping. This implies that superconductivity can only
The layered structure of the ReFeAsO, where the “Re” be obtained by introducing extra electrons rather than
represents different rare earth elements Gd, Sm, Nd, Pr, Ce
and La. By introducing oxygen vacancies in the crystalline “holes” (provided by positive ions) into the structure of the
lattice, the IOP scientists successfully induce high-Tc material. In only a month, however, the new results from
superconductivity in all the six lines of compounds with this
structure. Wen’s group subverted this hypothesis by successfully
Bulletin of the Chinese Academy of Sciences 145BCAS Vol.22 No.3 2008
inducing superconductivity in hole-doped materials of
By courtesy of Dr. Ren Zhi’an.
the same system. If confirmed by further experiments,
this result might also provide some novel thoughts for the
related exploration.
Looking into the future
The newly made progresses in iron-based materials,
the only high-Tc system other than cuprate chemicals to
date, might lead to greater clarity in superconductivity
mechanism, one of the most abstruse problems in
condensed matter physics, as believed by the researchers
and some renowned theorists, including Nobel Prize
The crystals of SmFeAsO, in which superconductivity at a Tc as
winner Philip Anderson with the Princeton University high as 55 K can be achieved by introducing oxygen vacancies.
of USA, as reported by the Science Magazine. Some The sample clearly appears a layered structure.
researchers, including some from the IOP groups, are more
cautious, however, believing that there is still a long way the excellent team of scientists. Some young scientists have
to go before we can really knock on the door to the core made outstanding contributions during the few months
mysteries of HTSC mechanism. since their joining us, like Dr. CHEN Genfu with Prof.
Nevertheless, the people are optimistic about the future Wang Nanlin’s team and Dr. REN Zhi’an with Prof. Zhao’s
because of something beneath the surface. “This time we group. We still have problems, of course. Most scientists
are thought to have taken over the lead,” remarks Director are expecting more stable support from the government
Wang: “China is becoming a strong country in science due and more reasonable an evaluation mechanism, given their
to the increased investment in fundamental research and essential roles in generating innovative results.”
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