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1.
<正>Driven by powerful demand and knowledge system innovation,science and technology are advancing by leaps and bounds,showing signs of transformative breakthroughs in solving some key science and technology issues.There is a good possibility that science revolution and technology revolution will take place,either successively,or in an interactive or co-existing way in the future.The ST breakthroughs will give rise to new industries and expedite an industrial revolution,and their impact on overcoming bottlenecks of sustainable socioeconomic development might be beyond expectations.1.Energy and resources In terms of energy,under the pressures of both  相似文献   

2.
1.Current provisions and main views The provisions concerning colours claimed in design patent are set forth in Rules 27 and 28 of the Implementing Regulations of the Patent Law(the Implementing Regulations for short).Rule 27,paragraph two of the Implementing Reg- ulations provides that"where an application for a patent for design seeking concurrent protection of colours is filed,a drawing or photograph in colour shall be submitted in two  相似文献   

3.
To address the current energy crisis, people are exploring new ways of synthesizing fuels with biomass. As biomass contains nearly 50% of oxygen in addition to hydrogen and carbon in its composition, the key to turning it into high-grade fuel for an internal-combustion engine lies in the technology that could liquefy biomass via deoxidation by making the best use of its contents of hydrogen and carbon without adding additional hydrogen or generating water.  相似文献   

4.
A healthy human body is equipped with a powerful immune system for resisting the attack of invading microorganisms. Unfortunately, the system sometimes goes awry and attacks the body itself.Autoimmunity is the failure of an organism to recognize its own constituent parts as"self," resulting in an immune response against its own cells and tissues. A disorder that results from such an aberrant immune response is termed an autoimmune disease.  相似文献   

5.
In today's society where science and technology are undergoing rapid development,and enterprises competing each other primarily with advanced technologies in which they enjoy their own intellectual property right,a major part of an enterprise's business activities is that patented technolo- gy and technical secret(or known-how)are taken as goods of technical trade and that R&D of hi-tech achievements are undertaken by way of conclusion of contracts.It is worth at- taching importance to how to ensure the legitimacy and va-  相似文献   

6.
For today‘s civilized world,with its dotcoms, sitcoms. ATMs,and ATVs.the first 3.5 billion years of life on Earth are a bit of an emharrassment.It was only a few hundred million years ago that trilobites prowled the seas, More primitive life subscribed to two or three basic lifestyles: algal mat spineless worm, or bacterial blob. Before that, in the Archean Eon more than 2. 5 billion years ago-well, that kind of life is what Lysol is for.  相似文献   

7.
Part I How speaking and writing differSpeech can be broken down into pronunciation and intonation,accuracyand fluency,or it can be categorized in terms of strategies,or it can be regardedas a form of interaction and analyzed using the methods of pragmatics or dis-course analysis.The problem is that in the course of a normal conversation,allof these aspects are important.If testers try to separate out the strands,theymay well find that the ecology of speaking is different in different successf…  相似文献   

8.
Although both the generalpurpose genotype hypothesis and the hypothesis about the evolution of invasiveness predict that invasive species are characterized by particular traits that confer invasiveness, what these traits are still remains unclear. A theory put forward by a CAS botanist and colleagues suggests that the success of an invasive plant in a new habitat is due to the allocation of more nitrogen to its photosynthesis. As reported in a recent issue of Oecologia, the hypothesis has been supported by their research on the metabolic comparison between an invasive shrub and five native plants.  相似文献   

9.
BCAS： It is the first ime that an ISRSE symposium is held in China. What＇s your impression about this meeing？ Dr. Briggs： This is about the 7 th or 8 th of ISRSE meetings which I attended over the last 15 years or so. The Beijing meeting is very well organized and very efficient. The program is very good. There are a lot of high quality speakers. I＇m impressed by the way that the program is being put together by the overall organization in Beijing which is excellent.  相似文献   

10.
PIWI-interacting RNAs(piRNAs) are a complex class of small non-coding RNAs that are mostly 24–32nucleotides in length and composed of at least hundreds of thousands of species that speciically interact with the PIWI protein subfamily of the ARGONAUTE family. Recent studies revealed that PIWI proteins interact with a number of proteins, especially the TUDOR-domain-containing proteins, to regulate piRNA biogenesis and regulatory function. Current research also provides evidence that PIWI proteins and pi RNAs are not only crucial for transposon silencing in the germline, but also mediate novel mechanisms of epigenetic programming, DNA rearrangements, m RNA turnover, and translational control both in the germline and in the soma. hese new discoveries begin to reveal an exciting new dimension of gene regulation in the cell.  相似文献   

11.
<正>Chinese Academy of Sciences and the German National Academy of Sciences Leopoldina stand united in their endeavor to promote the scientific spirit and to increase scientific excellence. The oldest academy in the West and the strongest academy in the East make the following declaration on the role and value of basic research and scientific advancement.Humankind is facing a broad range of serious challenges which are of global nature and effect. Examples are climate change, resource shortage or an uneven development, which  相似文献   

12.
 1)  The Compositae in Tibet so far known comprise 508 species and 88 genera, which nearly amounts to one fourth of the total number of genera and one third of the total number of species of Compositae in all China, if the number of 2290 species and 220 genera have respectively been counted in all China. In Tibet there are all tribes of Com- positae known in China, and surprisingly, the large tribes in Tibetan Compositae are also large ones in all China and the small tribes in Tibet are also small ones in all China. Generally speaking, the large genera in Tibet are also large ones in all China and the small genera in Tibet are likewise small ones in all China. In this sense it is reasonable to say that the Compositae flora of Tibet is an epitome of the Compositae flora of all China.      In the Compositae flora of Tibet, there are only 5 large genera each containing 30 species or more. They are Aster, Artemisia, Senecio, Saussurea and Cremanthodium. And 5 genera each containing 10—29 species. They are Erigeron, Anaphalis, Leontopodium, Ajania, Ligularia and Taraxacum. In addition, there are 77 small genera, namely 87% of the total of Compositae genera in Tibet, each comprising 1—9 species, such as Aja-niopsis, Cavea and Vernonia, etc.      2)  The constituents of Compositae flora in Tibet is very closely related to those of Sichuan-Yunnan provinces with 59 genera and 250 species in common. Such a situation is evidently brought about by the geographycal proximity in which the Hengtuang Shan Range links southeastern and eastern Tibet with northern and northwestern Sichuan- Ynnnan.  With India the Tibetan Compositae have 59 genera and 132 species in common, also showing close floristic relationships between the two regions. Apparently the floris- tic exchange of Compositae between Tibet and India is realized by way of the mountain range of the Himalayas.  The mountain range of the Himalayas, including the parallel ranges, plays a important role as a bridge hereby some members of the Compositae of western or northern Central Asia and of the northern Africa or of western Asia have migrated eastwards or southeastwards as far as the southern part of Fibet and northern part of India, or hereby some Compositae plants of eastern and southeastern Asia or Asia Media have migrated northwestwards as the northern part of Central Asia.      Some of the species and genera in common to both Tibet and Sinjiang indicate that this weak floristical relationship between these regions is principally realized through two migration routes: one migration route is by way of the Himalayas including the parallel ranges to Pamir Plataeu and Tien Shan, or vice versa. The other migration route is by way of northern Sinjiang to Mongolia, eastern Inner Mongolia, southwards to Gansu, Qinghai (or western Sichuan), eastern Tibet up to the Himalayas, or vice versa.      However, Tibet is not entirely situated at a migration crossroad of the floral ele- ments. An ample amount of the data shows that Compositae flora have a particular capability of development in Tibet. of the total number of species of Tibetan Com- positae, 102 species and 1 genus (Ajaniopsis Shih) are endemic. Besides, 8 genera are re- gional endemics with their range extending to its neighbourhood. The higher percentage of endemics at specific level than at generic in Tibetan Compositae may be a result of active speciation in response to the new enviromental conditions created by the uplifting of the Himalayas.  The flora in Tibetan Plateau as a whole appears to be of a younger age.       3) The uprising of the Himalayas and of the Tibetan Plateau accompanied by the ultraviolet ray radiation, the microthermal climate and the high wind pressure has, no doubt, played a profound influence upon the speciation of the native elements of Tibetan Compositae. The recent speciation is the main trend in the development of the Com-positae flora native in Tibet in the wake of upheaval of the plateau.  相似文献   

13.
Biological soil crust is a complex organic integrity of cyanobacteria, green algae, lichens and mosses, fungi, and other bacteria. This is a common and widespread phenomenon in desert areas all over the world. Biologically,this kind of soil crust differs a lot from physical ones in terms of physical and chemical properties, and become important biological factors in vegetation succession. Despite its unassuming appearance, the crust plays a significant role in the desert ecosystem, involving the process of soil formation, stability and fertility,the prevention of soil erosion by water or wind, the increased possibility of vascular plants colonization, and the stabilization of sand dunes.  相似文献   

14.
Restoration forestry (forest rehabilitation) or re-vegetation is one effective measure to solve environmental problems, notably soil erosion. It may be further stimulated by the Clean Development Mechanism for carbon sequestration. However, there is an intensive and on-going debate about the adverse effects arising from afforestation in dryland areas, such as soil drying up which may cause further damage to the success of forest restoration, and the water yield reduction from watershed which may harm the regional development. On other hand, some preliminary studies showed a possibility that these adverse effects may be diminished more or less by properly designing the system structure and spatial distribution of forest/vegetation in a watershed. However, it is urgent to develop an evidence-based and sustainable new forestry policy for harmonizing forest-water interrelation. As a leading country in afforestation, China is beginning to develop a more trans-disciplinary and cross-sectoral forestry policy for harmonizing forestry development with water management. The main points of the changing new forestry policy should include: (1) Establishing a regional development strategy focusing on harmonized forest-water relations; (2) Taking forest-water interactions as an important part of evaluation; (3) Reducing the ’eco-water’ quota of forests through technical advancement; (4) Developing and extending water-adaptive forest management practices; (5) Strengthening forest ecohydrological research and decision support ability.  相似文献   

15.
Multiple morphological abnormalities of the sperm flagella(MMAF) are one of the major causes of male infertility and are characterized by multiple defects.In this study,we found that the coiled-coil domain-containing 189(Ccdc189) gene was predominantly expressed in mouse testes and that inactivation of the Ccdc189 gene caused male infertility.Histological studies revealed that most sperm from Ccdc189-deficient mice carried coiled,curved or short flagella,which are typical MMAF phenotypes.Immunoe...  相似文献   

16.
白洋淀水生植物区系初步分析   总被引：1，自引：0，他引：1  
The Baiyandian Lake lies at 115°56′ E. and 38°55′ N.  It is about 8 m above sea level, with an area about 312 square km.  There are abundant aquatic plants here, inc- luding flowering plants of 30 families, 46 genera, 66 species and 3 varieties besides one in- troduced species.  32 species are erect ones covering about 48.5% of the total number of species in this lake, 20 are submerged ones, about 30.3%, 9 are leaf-floating ones, about 13.6% and 5 are floating ones, 7.6%.  The soil at the bed of the lake is very fertile and the depth is appro- priate, favouring various plants.  The coverage is large, sometimes it may reach 100%, for example, in communities of Phragmites communis, Hydrilla verticillata,  Hydrocharis dubis, Trapa bicornis, etc. Although the Baiyandian Lake is located in the temperate zone, the floristic elements are complex.  There are tropic-subtropic elements and elements of high-frigid zone as well.  When compared respectively with the floras of the Lakes Jingbo Lake, Honghu Lake and Lugu Lake, the flora of this lake is found more similar to that of subtropic Honghu Lake than to those of the other lakes, which shows that it hase a character transitional between the south and the north in China.  Further studies of the floristic relationships are needed in order to exploit and use the resources of the aquatic plants in this lake.  相似文献   

17.
<正>In recent years,with the rapid development of interdisciplinary studies such as molecular biology,genomics and systems biology,and with the breakthroughs in genome sequencing and other technologies,molecular marker-assisted selection and transgenic technology gradually became two important means of plant/animal breeding.Despite of the achievements,however,there are a number of problems in molecular breeding that need to be addressed immediately.As the major agronomic and economic traits of plants or animals are usually very complex and controlled by multiple genes,the modifi cation of a single or several functional genes is inadequate for the overall improvement of the target’s complex traits.Thus efficient,targeted and  相似文献   

18.
<正>Introduction With enhancing and deepening globalization,it is apparent that our world where we live is becoming smaller and smaller(or we called it a‘village’).In terms of human resource management,some people extend that we are getting involved in more complicated HRM,or IHRM issues.In addition,a wide variety of business organizations are operated all over the world,some of which hiring a great quantity of employees and its subsidiaries are situated in different countries.(War-  相似文献   

19.
1.General framework of galaxy formation and evolution Galaxies are the building blocks of the universe,and we mankind live in the Milky Way which itself is a typical spiral galaxy.If one takes a look at an image photographed by a big telescope,e.g.the Hubble Space Telescope(HST) or the Sloan Digital Sky Survey(SDSS),except for a small fraction of stars in our Milky Way,most of the sources are  相似文献   

20.
As a result of their three- year studiesin Drosophilae (fruit flies), CAS scientists reveal that the memory and learning in the insect could be enhanced by stimuli com- bining olfactory (or smell) and visual signals. In its evolutionary history, an organism could develop various sen- sory modalities (or channels) in the form of sight, hearing, smell, taste, touch and pain. These modalities serve as interfaces or pathways for the brain to exchange data with the outside world. In the merciless…  相似文献   

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