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1.
Experimental grafting between cloves is very difficult with shoots, and so far has proved impossible with roots. Use has therefore been made of naturally occurring grafts in the study of sudden-death disease. Volunteer seedlings often grow up closely adpressed to old trees. If the old tree dies from sudden-death disease, the pole† usually survives, but occasionally it dies almost simultaneously with the old tree. The poles discussed invariably had an independent root system, but those which died were found to have their roots grafted to those of the old tree whilst poles which survived, although closely adpressed to the old tree, had no organic connexion with it. These observations cannot be reconciled with any but a pathogenic hypothesis as to the nature of the sudden-death disease.  相似文献   

2.
我国儿童药物处于市场需求大、竞争小、政策利好的环境中,面临着前所未有的发展机遇。分析了我国儿童药物的发展环境和市 场现状,并对儿童药物的市场开发策略给予了建议。  相似文献   

3.
Seaweed hydrocolloid markets continue to grow, but instead of the 3?C5% achieved in the 1980s and 1990s, the growth rate has fallen to 1?C3% per year. This growth has been largely driven by emerging markets in China, Eastern Europe, Brazil, etc. Sales of agar, alginates and carrageenans in the US and Europe are holding up reasonably well in spite of the recession. However, price increases to offset costs in 2008 and 2009 have begun to have a dampening effect on sales, especially in markets where substitution or extension with less expensive ingredients is possible. These higher prices have been driven by higher energy, chemicals and seaweed costs. The higher seaweed costs reflect seaweed shortages, particularly for carrageenan-bearing seaweeds. The Philippines and Indonesia are the dominant producers of the farmed Kappaphycus and Eucheuma species upon which the carrageenan industry depends and both countries are experiencing factors limiting seaweed production. Similar tightening of seaweed supplies are beginning to show up in brown seaweeds used for extracting alginates, and in the red seaweeds for extracting agar. The structure of the industry is also undergoing change. Producers in China are getting stronger, and while they have not yet developed the marketing skills to compete effectively in the developed world markets, they have captured much of their home market. China does not produce the red and brown seaweeds needed for higher end food hydrocolloid production. Stocking their factories with raw material has led to the supply problems. Sales growth continues to suffer from few new product development successes in recent years; although some health care applications are showing some promise, i.e., carrageenan gel capsules and alginate micro-beads.  相似文献   

4.
Lack of suitable nesting trees is an increasingly common issue for avian conservation given rampant habitat and tree destruction around the world. In the African savannah, habitat loss and particularly tree damage caused by elephants have been suggested as possible factors in the decline of large bird species. Given the recent declines of vultures and other scavenging raptors, it is critical to understand if nest availability is a limiting factor for these threatened populations. Loss of woodland, partially due to elephant populations, has been reported for the Mara‐Serengeti ecosystem. Data on characteristics of trees used for nesting were collected for white‐backed, lappet‐faced, white‐headed vulture, and tawny eagle nests in Masai Mara National Reserve, Kenya. Nest tree characteristics were compared with the distribution of a random subsample of trees to assess nest preferences and determine suitability of available trees. Nearest neighbor distances were estimated as well as availability of preferred nesting trees to determine if tree availability is a limiting factor for tree‐nesting vultures. Tree availability was found to greatly exceed nesting needs for African vultures and tawny eagles. We thus conclude that on a landscape scale, tree availability is not a limiting factor for any of the species considered here (white‐backed, lappet‐faced, white‐headed vultures and tawny eagles).  相似文献   

5.
Yu Z  Dai Y 《Biotechnology journal》2006,1(11):1253-1257
The Chinese biotech industry is going through a period of fast growth, and with its huge population, China is predicted to be the biggest single-country market in the world. However, the Chinese biotech industry has to tackle the critical issue of innovation, which should be the driving force for China's development into an advanced and responsible country. Here, in this article, the authors review the history of the Chinese biotech industry, exemplified by the development of genetically engineered drugs during the last 20 years, and also point out its the future.  相似文献   

6.
在查阅大量文献资料的基础上,结合作者的研究成果,对国内外黑莓(Rubus spp.)产业发展及研究现状进行了综述,并分析了存在的问题,阐述了中国黑莓产业的发展优势和产业化前景.目前黑莓在全世界的种植面积约为20 035 hm2,年产量1.5×105 ~2.0×105 t,栽培区域遍及各大洲,其中塞尔维亚的黑莓种植面积位居世界第一,美国的黑莓年产量居世界第一,亚洲仅中国种植黑莓;近几年来,罗马尼亚、波兰、墨西哥、智利、匈牙利、中国以及美国的黑莓种植面积增长较快;因黑莓极不易贮存,绝大多数鲜果用于加工.国外以常规育种技术为主、分子技术为辅培育出许多黑莓品种,栽培技术已经非常成熟,成功实现了机械化采收,并逐步推广黑莓的有机生产体系和大棚栽培技术.国外黑莓生产中面临的主要问题是经济、冻害和病虫害等.黑莓于1986年引入中国,从1994年开始推广,至2010年种植面积约4 500 hm2,主要集中在江苏省的溧水县、赣榆县和溧阳市,90%以上鲜果加工成速冻果出口.在国外引种和国内野生种质资源收集的基础上,中国的研究者开展了黑莓的选种和育种研究,并培育和筛选出适宜于本地种植的黑莓优良品种;黑莓的栽培、加工技术研究也取得了显著的成果,并研制出一些加工产品.当前中国黑莓产业主要面临主栽品种单一、农药残留量超标、栽培条件差等方面的问题,制约了黑莓产业的发展.由于黑莓适于低山丘陵栽培,具有结果早、见效快、营养价值高等优势,在中国具有广阔的发展前景.  相似文献   

7.
Cocoa production in Côte d’Ivoire (40% of the world market) has tripled in the past 35 years even as the country’s forests are depleted. The chocolate industry, concerned about production so concentrated in one country and its dependence on the forest, is trying to convince smallholders to obtain ‘cocoa certification.’ This scheme, while couched in environmental terms, aims to increase cocoa yields and recommends the removal of kola trees from cocoa plots. This advice, ultimately largely ignored by the cocoa farmers, reflects a lack of understanding of farmer practices and kola tree’s economic, social, and cultural role. The chocolate industry reveals its vision for agroforestry as limited to production and demonstrates an unwillingness to participate in the smallholder-driven innovation system that is transforming Ivorian cocoa cultivation.  相似文献   

8.

Background

Scuba diving fishing, predominantly targeting sea cucumbers, has been documented to occur in an uncontrolled manner in the Western Indian Ocean and in other tropical regions. Although this type of fishing generally indicates a destructive activity, little attention has been directed towards this category of fishery, a major knowledge gap and barrier to management.

Methodology and Principal Findings

With the aim to capture geographic scales, fishing processes and social aspects the scuba diving fishery that operate out of Zanzibar was studied using interviews, discussions, participant observations and catch monitoring. The diving fishery was resilient to resource declines and had expanded to new species, new depths and new fishing grounds, sometimes operating approximately 250 km away from Zanzibar at depths down to 50 meters, as a result of depleted easy-access stock. The diving operations were embedded in a regional and global trade network, and its actors operated in a roving manner on multiple spatial levels, taking advantage of unfair patron-client relationships and of the insufficient management in Zanzibar.

Conclusions and Significance

This study illustrates that roving dynamics in fisheries, which have been predominantly addressed on a global scale, also take place at a considerably smaller spatial scale. Importantly, while proposed management of the sea cucumber fishery is often generic to a simplified fishery situation, this study illustrates a multifaceted fishery with diverse management requirements. The documented spatial scales and processes in the scuba diving fishery emphasize the need for increased regional governance partnerships to implement management that fit the spatial scales and processes of the operation.  相似文献   

9.
Acacia auriculiformis Benth., Mimosaceae, has been introduced relatively recently as a plantation tree to the island of Unguja, Zanzibar. It has been reported to establish itself outside the plantations, but it is not known if the success of establishment depends on habitat quality. We investigated the occurrence of A. auriculiformis in 5-m-wide sample lines, which started from the edge of acacia plantations and reached farthermost the distance of 1 km. The results of 7.24 ha studied showed that: (1) A. auriculiformis occurred in most of the studied habitats in Unguja and appeared to be more abundant in deep soils than in shallow coral-derived soils. However, statistical analyses suggested that the species has little preference or avoidance towards any of the habitats, even though forests – the least disturbed habitats – seemed to have less acacias than other more disturbed habitats. (2) The number of acacias decreased rapidly with the distance from an acacia plantation, and most of the found acacias were still young, below three metres tall. Our results suggest that the invasion of A. auriculiformis is at its beginning in Unguja. If no preventive measures are taken, A. auriculiformis may have an increasing impact on local ecosystem in the future.  相似文献   

10.
Economic, environmental, and political issues arising in the last two decades have changed agricultural practice worldwide. While the agrochemical market has diminished, time and cost of R & D and regulatory restrictions have increased, thereby reducing profit margins dramatically. This has led to a change of strategy from screening whole organisms to screening diverse compounds, with high-throughput screening processes similar to those used in drug discovery. For large-scale high-throughput screening to efficiently facilitate storage, retrieval, preparation and tracking of compounds, the sample management process needs to be highly automated. The introduction of modern automated technology will help to address the problems faced by the agrochemical industry.  相似文献   

11.
在当前面对医疗市场激烈的竞争现状,医院如何立于不败之地,如何使医院建设保持一个良性发展势态,是医院管理者面临的严峻课题。各级医院应主动适应市场变化,大力推行市场营销,促进医院的建设与发展。讨论医院怎样运用现代营销理论来构建面向市场、符合医院行业特点的医院营销体系。  相似文献   

12.
The coffee berry borer Hypothenemus hampei (Ferrari) is the most serious pest of the world's most valuable tropical export crop. Since the last review on this insect was published six years ago, many new studies have contributed to an improved insight into the biology and ecology of the beetle, and have indicated new avenues for integrated and biological control. The latest developments in research, both laboratory and field, on the pest, its natural enemies and their implications for integrated control of H. hampei are summarized, with a particular focus on the situation in The Americas. Lately, the global coffee industry has changed radically; it has suffered a long cycle of lowest-ever world market prices caused by overproduction and technological change. At the same time, the advent of sustainable certification schemes has had a major impact on the industry. The role of integrated pest management and biological control of H. hampei in an era of changes in the coffee industry is discussed.  相似文献   

13.
Removing the apical cloves from the excised garlic scapes could delay the senescence of scape and decrease the rate of dry matter loss during storage. The ABA content of all the portions of the scapes with apical cloves is decreased as the prolongation of storage period; but its content of all the portions of the scapes with the cloves reaches their peak one after another within the first 6 days of the experiment period. The peak of ABA in the apical cloves appears earliest; the ABA content of any portion of the scapes is lower than that of the cloves, and gradually decreases from upper to lower portions, and the peak of ABA content appears in the sequence as above. Exogenous ABA which is added to the top of the scapes without cloves would simulate the function of the apical cloves in part and accelerates the chlorophyll destruction and senescence of the scapes. No ethylene can be detected by the G. C., in the process of senescence. The authors suggest that ABA is mainly synthesized in the cloves, and then transported into the scapes from there. In the senescence of garlic scapes and in the redistribution of material between the apical cloves and the scapes (the relation between the sink and source), ABA functions as transporting information and promoting senescence but ethylene has not such a function. The senescence of garlic scape could be divided into two stages: first the static phase and second, the active phase.  相似文献   

14.
我国是栽培食用菌最早的国家,食用菌产量居世界首位,食用菌产业化发展已具有一定规模。针对食用菌产业中存在的发展不均衡、生产规模偏小等问题,提出了开拓国内外市场、增加产品特色等发展对策,为加快食用菌产业化发展提供思路。  相似文献   

15.
森林退化/衰退的研究与实践   总被引:7,自引:3,他引:4  
森林退化可以理解为森林面积减少、结构丧失、质量降低、功能下降;森林衰退则是森林退化的一种形式,指森林(树木)在生长发育过程中出现的生理机能下降、生长发育滞缓、生产力降低甚至死亡,以及地力衰退等状态.国内外研究表明,森林采伐/毁林是造成森林面积减少的最主要原因,有关森林采伐/毁林引起的森林退化研究主要集中在森林退化的后果、国家/国际政策的影响、加强全球性合作以及寻求解决途径等方面.森林衰退原因可归纳为:工、农业污染,自然胁迫/致衰因子,林分动态发生变化,森林衰退病或生态病,人工纯林以及纯林连栽导致的地力、生产力衰退等.中国的森林退化/衰退现状与世界各地森林退化基本一致,但由于历史原因,中国森林退化又有其自身特点:近一个世纪的强烈人为干扰,使大部分原始天然林退化为次生林;中国拥有世界上最多的人工林,且多数人工林均具有质量差、功能低等衰退特征.本文在综述森林退化/衰退研究与实践基础上,提出中国现代森林退化/衰退的的主要原因,给出中国森林退化/衰退的基本对策.  相似文献   

16.
The rightful emphasis on collaboration between the public and private sectors in solving the world's health problems, especially those of the poor in the developing world, relies on industry developing new technologies with the support of government and foundations. However, certain products, despite their potential to have a great impact on disease in the developing world, will not be developed by industry because they carry the risk of lawsuits owing to possible severe adverse reactions--risks that are not counterbalanced by potential profit of products that are of limited use in the developed world. Freund's incomplete adjuvant (FIA) is one such example that is better developed in the public sector. In this article, we present the evidence that has led to our interest in FIA, evidence of its potential benefit in vaccines against blood-stage malaria, and the way forward to make safe, effective and affordable vaccines for malaria and other serious diseases in the developing world.  相似文献   

17.
18.
蒜苔在切除珠蒜后可减少贮存中干物质的损失,延缓衰老,在切口处施加外源ABA可加速苔干叶绿素的破坏和组织的老化,气相色谱与色质联用法检测完整蒜苔和无珠蒜蒜苔各部分组织中ABA含量在衰老过程中的变化,发现无珠蒜苔干上,中,下各段ABA含量在衰老进程中是逐步减少的,变化幅度小,而带有珠蒜的苔干各相应段和珠蒜的ABA含量均有一迅速增加而后减少的过程,珠蒜的ABA含量最大,ABA含量高峰出现时间最早,苔干各段ABA含量按上,中,下顺序依次减少,高峰出现的时间也是由上至下依次推迟,没有发现蒜苔在衰老过程中有乙烯放出,外加乙烯对其衰老进程影响不大,本文认为珠蒜是蒜苔衰老的关键部位,能加速苔干衰老的ABA主要是在珠蒜中合成的,并自上向下极性运往苔干组织,进而动员物质的再分配,起着信息传递作用,蒜苔的衰老过程可分为“准备期”和“活跃期”两个阶段。  相似文献   

19.
The pharmaceutical industry is one of the largest and most profitable industries in the world, and in the United States, the industry has a particularly privileged economic position. Yet the cost of drugs in the United States is higher than anywhere else, due largely to the fact that the industry is focusing increasingly on marketing rather than on the development of meaningful new medications: available evidence does not support claims of great expense for the development of new drugs. Because of its vast resources, the pharmaceutical industry has assumed an increasing influence in medicine, which, given the differences in values and priorities between medicine and the drug companies, is a cause for concern. The pharmaceutical industry has acted to maximize its profits in ways that frequently conflict with medicine's need for truth and full disclosure. Indeed, the industry has arguably worked to compromise physicians' judgments, as well as academic standards. As a result, despite government regulation there have been unnecessary adverse effects from drugs. The experience with butorphanol (Stadol) exemplifies problems in the current system and the harm that can result. Changes are suggested to make the pharmaceutical industry more responsive to the needs of patients and physicians.  相似文献   

20.
Studies of the extraction of non-timber forest products have shown that the standing rainforest may be more valuable than alternatives involving deforestation

Although this article is about placing a value on rainforest, it begins by stressing the importance and value of rainforest for its environmental function, particularly for the control of world climate patterns. It is then shown how rainforest peoples depend on the plants around them and in some study areas were found to have a use for every tree on the one-hectare plots. It is therefore not surprising that the rainforest can contain many non-timber forest products (NTFPs) of commercial potential, some of which such as rubber latex and Brazil nuts have been in the market economy for many years. A summary is given of various attempts to place a value on rainforest for its NTFPs. Each of the three studies showed that the extraction of these products could be more valuable than alternative land uses involving deforestation. Various rainforest countries such as Brazil, Guatemala, and Indonesia have set up extractive reserves where local people are allowed to extract NTFPs but not to clear cut the forest. Extractive reserves have slowed down deforestation in some areas, but only provide a meagre subsistence existence for their inhabitants, so while they are useful, they are not a panacea that will solve all the conservation problems of tropical rainforest.  相似文献   

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