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51.
近年,由于日本人饮食习惯的急速的西方化,过去较少见的癌症、心脏病、糖尿病等疾病日益激增。以附加功能性于大米为目的,2001年开发出了采用浸泡式工艺的发芽糙米,发芽糙米所含GABA对高血压及糖尿病等生活习惯病具有预防效果。通过将富含发芽糙米的功能性成分之一的GABA附加于免淘洗米,开发出功能性免淘洗米(免淘洗GABA米)。利用功能性液化液,制成具有降压等作用的免淘洗功能性包膜米。同时,利用发芽糙米等为功能性原料可开发一系列深加工产品。 相似文献
52.
公益林与商品林分类指标体系及技术标准的研究 总被引：19，自引：0，他引：19
林业分类经营是林业部提出的一项深化林业改革的重要措施,如何科学合理地划公益林与商品林,是当前实施林业分类经营战略迫切需要解决的问题。本文从系统、可行、科学的角度对森林功能性分类系统,划分公益林与商品林的分类指标体系及技术指标进行了探讨。 相似文献
53.
Danilo G. R. Castanho Cláudia P. de Deus Jansen Zuanon Sergio Santorelli Rafael P. Leitão Fabrício B. Teresa 《Ecology of Freshwater Fish》2020,29(4):533-541
The consequences of over-exploitation may seriously impair the integrity and functioning of ecosystems. When loss of species is accompanied by the loss of ecological processes, the effects are no longer just taxonomic and may affect the stability of the environments. Ornamental fishing is one of the main economic activities of the middle Negro River. Such activity is directed to a small number of species and has the Cardinal Tetra (Paracheirodon axelrodi) as the main target species. Given the potential effects this pressure and the lack of information on its consequences, the present study analysed, through simulations, the possible effects of depletion of ornamental fish populations on the functional structure of fish assemblages, represented by functional diversity (FD) and functional redundancy (FR) indexes. We sampled 13 streams exploited by the ornamental fishery, where we collected 4,286 specimens of 110 species, of which 22 were targeted as ornamental fishing. We found that the ornamental species corresponded, on average, to 27.8% of the species and 33.3% of the FD of the assemblages. In a scenario of complete exclusion of ornamental species, local communities would lose 24.6% of the FD and reduce up to 12% of the FR. With these results, it is possible to infer that the local extinction of exploited species would cause negative impacts on the multifunctionality and the resilience of the streams ecosystems. In this way, we emphasise the need for proper management of the ornamental fisheries aiming to the sustainability of the activity and to the conservation of ecosystem functionality. 相似文献
54.
利用 PC机和 B& K2 2 30声级计内部相关电路组成新测量系统 ,通过声级计对系列稳定纯音的测量实现对该新系统的标定 .在此基础上 ,应用信号数字处理技术进行编程 ,使系统具有音频信号频谱分析、图形显示和打印等功能 .结果表明 ,在测量精度不变的前提下 ,新测量系统在测量和数据处理方面明显优于原声级计 相似文献
55.
Tania De Almeida;Xavier Arnan;Yvan Capowiez;Mickaël Hedde;François Mesléard;Thierry Dutoit;Olivier Blight; 《Land Degradation u0026amp; Development》2024,35(4):1284-1295
Global changes call for more nature-based solutions, especially in nature conservation involving ecological restoration. Current methods essentially based on civil engineering are both expensive and costly in non-renewable energy consumption and pollution terms. The non-sustainability of these techniques is leading to the direct use of certain species to restore degraded ecosystems. Ants, because of their central role in ecosystem functioning and their occurrence on almost all terrestrial ecosystems, are promising candidates for environmental monitoring and such ecological restoration projects. We provide here a narrative review of the ecological functions performed by ants, and we take stock of how ants are currently considered in passive and active restoration. We then propose a trait-based approach to facilitate their use by practitioners in future restoration projects. We list and discuss both life-history traits relevant for environmental monitoring and functional traits known to affect abiotic (physical and chemical soil properties) and biotic (plant and fauna communities) components. 相似文献
56.
Sharifah N. Syed Jaafar Johanna Baron Susanne Siebenhandl‐Ehn Thomas Rosenau Stefan Böhmdorfer Heinrich Grausgruber 《Plant Breeding》2013,132(6):546-552
Due to their antioxidant activity, anthocyanins are of increasing interest for nutritionists, food scientists and plant breeders. Anthocyanins in wheat grains are expressed in either the pericarp or aleurone layer. Previous studies revealed that different anthocyanins are present in wheat varieties carrying genes for either the purple pericarp or the blue aleurone trait. Progeny from crosses between red‐, purple‐ and blue‐grained wheat varieties were selected over several cycles for grain colour by visual scoring. Bulked F5 grains were evaluated for their total anthocyanin content by UV‐VIS spectrophotometry and HPLC‐MS. The results demonstrate that it is possible to increase the anthocyanin content by the combination of the different genetic backgrounds for purple pericarp and blue aleurone, even though the majority of progeny were within the range of the purple‐ and blue‐grained check varieties. Visual scoring for grain colour is efficient, reliable and fast for selection in early breeding generations. Advanced breeding lines with high anthocyanin content can be identified by simple extraction methods and spectrophotometric measurements. 相似文献
57.
《植物养料与土壤学杂志》2017,180(4):425-429
The microbial habitat is rarely studied in soil microbial ecology even though microbial cells are exposed and adapt to their local environmental conditions. The physical environment also constrains interactions among organisms. The nature of microbial communities and their functioning can only be fully understood if their habitat is accounted for. Here, I describe the soil microbial habitat and show how our understanding of microbial functioning has been shaped by this line of investigation. 相似文献
58.
Stress of aquatic animals occurs due to physical and physiological disturbances in the aquatic environment or system when transportation, crowding, handling or changes of physical and chemical factors take place. There are three regulatory systems having a vital role in stress response: the neural, endocrine and immune systems. Fish exhibit multiple genomic and physiological responses to adjust the compensatory or adaptive mechanism that allows them to mitigate the stressors, maintain their haemostasis and survive. In this review, we describe multiple important genes that are associated with responses to environmental and husbandry stressors and that could be used as biomarkers of environmental and husbandry stressors in fish. The described environmental and husbandry stressors include salinity, temperature, hypoxia and hyperoxia, confinement, density and handling. The main role of stress response in aquatic animals is to compensate or adapt their biological systems and arrange the metabolism to afford the energy required by the stressor and a wide array of metabolic processes and pathways are involved. We summarized and discussed highly significant genes in several organs and tissues that are involved and active during this adaption process. The traditional stress biomarkers in some circumstances have some difficulties in interpretation of results and lead to tricky diagnosis and searching and understanding alternative tools is critical for aquaculture, fisheries and fish welfare. Using genomic tools to study the candidate genes associated with stress responses are often unique signatures or imprints of specific stressors and could determine early signs of stressors. 相似文献
59.
Although nucleotides (NT) have long been implicated as feed attractants in both vertebrate and invertebrate species, research into potential growth and health benefits of dietary NT in aquaculture species has just been implemented in early 2000s. To date, research pertaining to NT supplementation in aquafeed as functional nutrients has shown rather consistent and encouraging, beneficial results in fish and shrimp health management. Dietary NT serve a marked role to enhance growth in early stages of development, improve reproductive performances of brood fish, enhance larval quality, increase stress and disease resistance, modulate immune functions and improve intestinal morphology and gut microbiota of fish and shrimp. NT have also been used as functional supplement in alternative protein based diet, where NT was found as an effective supplement to increase the efficiency of utilizing alternative proteins. However, still there are numerous gaps in existing knowledge about exogenous NT administration to fish and shrimp including various aspects of digestion, absorption, metabolism, administration duration and age/size‐related responses. Adoption of different molecular technologies, like proteome modification and study of several gene expression pattern related to growth, immunity, gut health and stress resistance in details are important for exploring the underlying mechanisms of NT functions in improved growth and health performances of fish and shrimp. Efforts are also needed on production technologies to reduce the NT cost. Moreover, extensive research information is also required regarding the use of NT in alternative protein and lipid based diet to develop cost‐effective, ecofriendly functional aquafeed in near future. 相似文献
60.
Nabeel T. Alzuwaid Mike Sissons Barbara Laddomada Christopher M. Fellows 《Cereal Chemistry》2020,97(2):304-315