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81.
Neha Babbar Winnie Dejonghe Monica Gatti Stefano Sforza 《Critical reviews in biotechnology》2016,36(4):594-606
Pectin containing agricultural by-products are potential sources of a new class of prebiotics known as pectic oligosaccharides (POS). In general, pectin is made up of homogalacturonan (HG, α-1,4-linked galacturonic acid monomers) and rhamnogalacturonan (RG, alternate galacturonic acid and rhamnose backbone with neutral side chains). Controlled hydrolysis of pectin containing agricultural by-products like sugar beet, apple, olive and citrus by chemical, enzymatic and hydrothermal can be used to produce oligo-galacturonides (GalpOS), galacto-oligosaccharides (GalOS), rhamnogalacturonan-oligosaccharides (RGOS), etc. However, extensive research is needed to establish the role of POS, both as a prebiotic as well as therapeutic agent. This review comprehensively covers different facets of POS, including the nature and chemistry of pectin and POS, potential agricultural residual sources of pectin, pre-treatment methods for facilitating selective extraction of pectin, identification and characterization of POS, health benefits and important applications of POS in food and feed. This review has been compiled to establish a platform for future research in the purification and characterization of POS and for in vivo and in vitro studies of important POS, so that they could be commercially exploited. 相似文献
82.
Patricia P. Iglesias Eduardo M. Soto Ignacio M. Soto Betina Colines Esteban Hasson 《Journal of evolutionary biology》2018,31(7):957-967
Closely related species often differ in the signals involved in sexual communication and mate recognition. Determining the factors influencing signal quality (i.e. signal's content and conspicuousness) provides an important insight into the potential pathways by which these interspecific differences evolve. Host specificity could bias the direction of the evolution of sexual communication and the mate recognition system, favouring sensory channels that work best in the different host conditions. In this study, we focus on the cactophilic sibling species Drosophila buzzatii and D. koepferae that have diverged not only in the sensory channel used for sexual communication and mate recognition but also in the cactus species that use as primary hosts. We evaluate the role of the developmental environment in generating courtship song variation using an isofemale line design. Our results show that host environment during development induces changes in the courtship song of D. koepferae males, but not in D. buzzatii males. Moreover, we report for the first time that host rearing environment affects the conspicuousness of courtship song (i.e. song volume). Our results are mainly discussed in the context of the sensory drive hypothesis. 相似文献
83.
Masahito Morita 《Population Ecology》2018,60(1-2):143-154
Recently, statistical analyses of demographic datasets have come to play an important role for studies into the evolution of human life history. In the first part of this paper, I highlight fertility decline, an evolutionarily paradoxical phenomenon in terms of fitness maximization. Then, I conduct a literature review regarding the effects of socioeconomic status on the number of offspring, especially in modern developed, (post-)industrial, and low-fertility societies. Although a non-positive relationship between them has often been recognized as a general feature of fertility decline, there actually exists a great deal of variation. Based on the review, I discuss the association between socioeconomic success and reproductive success, and tackle an evolutionary question as to why people seek higher socioeconomic success that would not directly lead to higher reproductive success. It has been suggested that, in modern competitive environments, parents should set a higher value on their investment in children, and aim to have a smaller number of high-quality children. Also, parents would maintain higher socioeconomic status for themselves so as to provide high-levels of investment in their children. In the second part, I broadly consider seemingly evolutionarily (mal)adaptive outcomes besides fertility decline, including child abuse, menopause, and suicide. The integration of the major three approaches to human behavioral and psychological research (behavioral ecology, evolutionary psychology, and cultural evolution) could lead to a deeper understanding. I provide a model for the integrated approach. Rich empirical evidence accumulated in demographic studies, especially longitudinal and cross-cultural resources, can assist to develop a theoretical framework. 相似文献
84.
Janet B. Croft David S. Freedman Nora L. Keenan David P. Sheridan Caroline A. Macera Fran C. Wheeler 《Obesity (Silver Spring, Md.)》1996,4(6):505-512
Few epidemiologic studies have investigated the impact of body mass index, low educational attainment, cigarette smoking, and physical activity on the considerable black-white difference in waist-to-hip ratio. These relationships were assessed with multi-variable linear regression among 3,094 adults (24% black) who were examined in 1987 in South Carolina. The unadjusted mean waist-to-hip ratio was lower for black men than for white men (-0.03 units) and higher for black women than for white women (+0.03 units). After adjustment for age, body mass index, education, smoking, and physical activity, the black-white difference in mean waist-to-hip ratio was ?0.02 units (p<0.001) among men and +0.01 units (p<0.01) among women. Although differing distributions of age, body mass index, and educational attainment accounted for a 59% reduction in the black-white difference among women, these factors did not explain the difference among men. Thus, these results suggest that other environmental or biologic factors may also play an important role in the marked variation in body fat distribution between the two ethnic groups. The results also support the importance of the prevention of cigarette smoking and overweight in potentially preventing abdominal obesity in both black adults and white adults. 相似文献
85.
Ian Oliver Alan Ede Wendy Hawes Alastair Grieve 《Ecological Management & Restoration》2005,6(3):197-205
Summary In 2002 the Environmental Services Scheme (ESS) was launched in New South Wales, Australia. Its aim was to pilot a process to provide financial incentives to landholders to undertake changes in land use or land management that improved the status of environmental services (e.g. provision of clean water, healthy soils, biodiversity conservation). To guide the direction of incentive funds, metrics were developed for use by departmental staff to score the benefits of land use or land management changes to a range of environmental services. The purpose of this paper is to (i) report on the development of one of these metrics – the biodiversity benefits index; (ii) present the data generated by field application of the metric to 20 properties contracted to the ESS; and (iii) discuss the lessons learned and recent developments of the metric that aim to make it accessible to a wider range of end-users and applications. 相似文献
86.
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88.
生命周期方法在产业共生系统环境效益评价中的应用——研究进展及问题分析 总被引:1,自引:0,他引:1
近年来,产业共生作为产业生态学最具特征的领域引起了相关研究者的广泛关注。当前的研究逐渐从产业共生系统的定性描述分析转向定量的系统评价上。传统的产业共生系统环境效益评价仅仅关注共生系统本身,而忽视了占环境影响20%—50%的上、下游过程及替代过程的环境影响,为了得到客观的、系统的环境影响评价,将生命周期分析方法引入产业共生效益评价显得尤为重要。首先回顾了生命周期分析方法在产业共生研究中的发展过程,接着评述了3种生命周期分析方法在产业生态研究中的优劣势。并重点分析了将生命周期思想引入产业共生效益评价方法存在的功能单位设定问题及系统边界的选择问题。最后,呼吁为避免隐形污染的转移,必须尽快将生命周期分析的方法和管理理念引入我国生态工业园设计、规划、评价和管理的全过程中。 相似文献
89.
Marine Protected Areas (MPAs), if well designed and managed, can produce conservation benefits to fish assemblages within no-take zones and fishery benefits in neighboring areas through ‘spillover’. However, although plenty of studies have provided evidence of the benefits produced within MPA boundaries, overall benefits to local fisheries, especially via spillover, seem to be still unclear. Because of the lost fishing grounds following an MPA establishment, local fishermen usually oppose MPAs. There is, therefore, the urgent need for a better understanding of the mechanism(s) through which MPAs can export fishable fish biomass towards adjacent fished areas, a process that could counterbalance the loss of fishing grounds. Here we review the literature on spillover for refining the terminology, detailing the underlying mechanisms and identifying both the existing and needed methodological approaches to measure spillover. Operationally, two types of spillover should be considered: ecological spillover (i.e. the net export of juvenile, subadult and adult biomass from MPAs outwards driven by density-dependent processes) and the fishery spillover (i.e. the proportion of this biomass that can be fished, taking into account regulations and accessibility). Underwater visual census and tagging/tracking may allow getting evidence of ecological spillover, while experimental catch data are essential to assess and monitor fishery spillover, which is the main component of MPAs that can provide direct benefit to local fisheries. 相似文献
90.
The young sperm gambit 总被引:3,自引:0,他引:3
Siva-Jothy 《Ecology letters》2000,3(3):172-174
Thermodynamic and oxidative damage to the condensed nuclear DNA of spermatozoa may result in age-related deterioration that results in zygote death. By definition, any such spermatozoan-age effects are direct (i.e. nonheritable) and, if they occur, females may be selected to avoid such costs. This paper examines the potential of spermatozoan-age effects to provide alternative explanations for several reproductive phenomena. 相似文献