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121.
Massimo Cordone Mario Lituania Caterina Zampatti Ubaldo Passamonti MD Gian Michele Magnano Paolo Tomà 《黑龙江环境通报》1989,9(11):745-750
A prenatal diagnosis of campomelic dysplasia in a primigravida is described. First level fetal ultrasonography demonstrated bowing and shortening of lower limbs. Second level examination allowed the correct diagnosis by demonstrating several skeletal anomalies pathognomonic of campomelic dysplasia. 相似文献
122.
Mario Giampietro 《Ambio-人类环境杂志》2002,31(6):466-470
本文从三个方面论述了保护原则的应用与转基因生物(GMOs)的调控之间的关系:①在应用保护原则时所出现的随意性,反映了一个更深层次的问题,即影响可持续性科学分析的认识论,需要我们区分"风险(risk)"、"不确定性(uncertainty)"和"无知(ignorance)"三个概念之间的差异;②在讨论进化这一科学问题时,我们不可能完全避免不确定性和无知,因此,就难以使用传统的风险分析方法(概率分布分析和精确的数值模拟),而应当选取来自其他科学领域(生态学一般原则或者隐喻)的替代方法;③生态风险的存在,不应当作为完全停止创新的理由,但保护原则的使用,可以使科学家们的理念从"存在合理性"(substantive rationality)(试图给出社会的最优化解决办法),转变到"过程合理性"(procedural rationality)(试图帮助社会找出"令人满意的"解决办法). 相似文献
123.
Literature shows that full-scale pure-oxygen activated sludge (O2-AS) wastewater treatment plants (WWTPs) generate effluents with higher dissolved-organic carbon (DOC) concentrations and larger high-molecular-weight fractions compared to air-activated-sludge (Air-AS) WWTP effluents. The purpose of this paper was to evaluate how gas supplied (air vs. pure oxygen) to sequencing-batch reactors affected DOC transformations. The main conclusions of this paper are (a) O2-AS effluent DOC is more refractory than air-AS effluent DOC; and (b) O2-AS systems may have higher five-day biochemical oxygen demand removals than air-AS systems; however, in terms of COD and DOC removal, air-AS systems are better than O2-AS systems. Analysis of a database from side-by-side O2- and air-AS pilot tests from literature supported these observations. 相似文献
124.
The molecular-weight distribution (MWD) of wastewater dissolved-organic carbon (DOC) was determined in samples from seven full-scale wastewater-treatment plants (WWTPs) that use different biological treatments (air activated sludge [air-AS], pure-oxygen AS [O2-AS], and trickling filters). The research objective was to determine how different biological treatments influenced the MWD of wastewater DOC. Primary sedimentation effluent DOC from most of the WWTPs exhibited a skewed distribution toward the low-molecular-weight fraction (MWF) (40 to 50%, < 0.5 K Daltons [KDa]). The Air-AS effluent DOC exhibited a centrally clustered distribution, with the majority of DOC in the intermediate MWF (0.5 to 3 KDa). The O2-AS effluent DOC exhibited a skewed distribution toward the high MWF (> 3 KDa). The removal of DOC by air- and O2-AS bacteria followed trends predicted by a macromolecule degradation model. Trickling-filter effluent DOC exhibited a skewed distribution toward the high MWF (50% DOC, > 3 KDa). 相似文献
125.
Thaís Pacheco Kasecker Mario Barroso Ramos-Neto Jose Maria Cardoso da Silva Fabio Rubio Scarano 《Mitigation and Adaptation Strategies for Global Change》2018,23(6):981-993
We developed an indicator that defines priority municipalities in order to facilitate the deployment of preventive policies and strategies for ecosystem-based adaptation to climate change (EbA) in Brazilian municipalities. Based on the premises that poor people are the population most vulnerable to climate change and that conservation and sustainable use of biodiversity and ecosystems are adaptive to climate change, our indicator uses three parameters: (1) poverty, (2) proportion of natural-vegetation cover, and (3) exposure to climate change. Thus, we searched for Brazilian municipalities that simultaneously belonged to the quartile of municipalities with the highest percentage of poverty, the quartile with the highest percentage of natural-vegetation cover, and the quartile with the highest exposure indices in two global climate models (Eta-HadGEM, Eta-Miroc). We found 398 (7.1%) EbA hotspots among 5565 Brazilian municipalities, which comprise 36% of the total area of native remnants in the country and are home to 22% of the poor people in Brazil. In their majority, these municipalities cover significant portions of the Amazon, Cerrado, Caatinga, and Atlantic forest, and indeed, these regions are recognised as some of the most vulnerable to climate change in the world. Considering the relevance of these biomes for the global water and nutrient cycle (Amazon), global food security (Cerrado), vulnerability to desertification (Caatinga), and biodiversity (all) we discuss the adaptive strategies in place, the need to bring them to scale, and existing policy gaps. Finally, in an effort to guide international and national investment and policies, we discuss how the approach described here can be applied to societies inhabiting tropical forests, savannas, and semiarid zones in other parts of the world. In particular, we propose that the indicator developed here is a simple and fast way to achieve early detection of priority municipalities for deployment of EbA action and policies, particularly in tropical developing countries. 相似文献
126.
Tiziana Romagnoli Giorgio Bavestrello Emellina M. Cucchiari Mario De Stefano Cristina G. Di Camillo Chiara Pennesi Stefania Puce Cecilia Totti 《Marine Biology》2007,151(2):537-552
The microalgal community associated with Eudendrium racemosum, a marine hydroid widely distributed in the Mediterranean Sea, was studied during an annual cycle, at monthly frequency,
in a coastal station of the Ligurian Sea. Microalgae were represented mainly by diatoms, which exhibited higher abundance
and biomass values between autumn and spring (max 46,752 cells mm−2 and 1.94 μg C mm−2, respectively), while during summer a significant decrease was observed (min 917 cells mm−2 and 0.013 μg C mm−2). High levels of abundance of filamentous cyanobacteria were observed in summer. Spatial distribution of epibiontic microalgae
showed a markedly increasing gradient from the basal to the apical part of hydroid colonies. Considering the growth forms
of diatom communities, motile diatoms (mainly small naviculoid taxa) were the most abundant in all the periods. Adnate (Amphora and Cocconeis spp.) were distributed mainly in the basal and central part of hydroid colonies and showed two peaks (autumn and summer).
Erect forms (mainly Tabularia tabulata, Licmophora spp., Cyclophora tenuis) were mainly distributed in the apical part of the colonies and showed their maximum densities in spring–summer. Tube-dwelling
(Berkeleya rutilans, Parlibellus sp.) were observed at low densities throughout the study period, without any significant temporal or spatial variability.
Comparing the microalgal communities on marine hydroid to those grown on mimic substrata placed in the sampling station during
summer, significantly higher values of abundance were observed in the hydroid, suggesting that microalgae may benefit from
the polyp catabolites. This fact was particularly evident for the adnate diatoms, whose temporal trend paralleled the cycle
of hydroid host. 相似文献
127.
Knowing how far away animals can detect food has important consequences for understanding their foraging and social behaviors.
As part of a broader set of field experiments on primate foraging behavior, we set out artificial feeding platforms (90 × 90 cm
or 50 × 50 cm) throughout the home range of one group of 22 brown capuchin monkeys, at sites where they had not seen such
platforms previously. Whenever the group approached such a new platform to within 100 m, we recorded the group's direction
and speed of approach, and the identity and distance from the platform of the group member that detected the platform or came
closest to it without detecting it. We used logistic regression on these data to examine the effects of group movement speed,
platform size and height, and focal individual age and sex on the probability of detecting the platform as a function of distance.
Likelihood of detecting a platform decreased significantly at greater distances – the probability of detecting a platform
reached 0.5 at 41 m from the group's center and 25.5 m from the nearest group member. These results show that detectability
of platforms by the entire group (9 adults, 13 juveniles) was less than twice that for single group members. Detectability
at a given distance decreased severely as the group moved faster; at their fastest speed, individuals had to approach a platform
to within less than 10 m to find it. The large platforms were significantly more likely to be detected than the small ones,
suggesting that increased use of larger food patches by wild primates may not necessarily reflect foraging preferences.
Received: 20 May 1996 / Accepted after revision: 5 April 1997 相似文献
128.
Self-purification ability of a resurgence stream 总被引:14,自引:0,他引:14
The self-purification ability of a resurgence stream has been investigated by taking samples along the course of a channeled tract made up of a first part in beaten soil (3.3 km) and a second in concrete (7.2 km). The study has been conducted by statistically processing pre-existent data, acquired monthly by analyzing waters at the beginning and at the end of the whole canal for 6 years, from 1995 to 2000 (historic data), and by performing specific experiments (recent data) to evaluate differently the self-purification capacity of the beaten soil section and that in concrete. A significant abatement of concentrations has been observed from historic data for ammonium, phosphates, turbidity, heavy metals and bacteria. From the recent data, all these parameters seem to decrease in the beaten soil tract. Whereas significant further decreases in the concrete tract were observed only for ammonium, phosphates and bacteria. For other parameters, e.g. pH, dissolved oxygen, chlorides, fluorides, sodium, and sulfates, a significant increase was observed from the historic data. 相似文献
129.
Collado Sergio Oulego Paula Alonso Saúl Díaz Mario 《Environmental science and pollution research international》2017,24(26):21262-21271
Environmental Science and Pollution Research - Flow cytometry has recently been presented as a research tool in the assessment of the viability/activity of activated sludge from municipal... 相似文献