首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到6条相似文献,搜索用时 0 毫秒
1.
Software is a key factor in the functioning of today’s world. Software is supposed to have some characteristics such as: reliability, security, etc., but it is not at all easy to find energy efficiency considered as being one of software’s most important features. Aspects related to Green Software have begun to be considered vital and basic, due to pressure from a society which is becoming more and more aware of environmental problems. In this paper we want to explore whether software companies, responsible for developing software, are aligning their strategies with environmental concerns. To do so, we have checked the Corporate Social Responsibility (CSR) policies of the ten most important software companies and looked at these documents with reference to the UN’s sustainable development goals. A well-defined method for carrying out the analysis of the CSR policies led the authors to identify which of the sustainability actions proposed can be classified within any of the software sustainability dimensions. The analysis of these actions shows that sustainability is considered in most of the companies; nonetheless, most attention is currently devoted to hardware-based initiatives intended to reduce the carbon footprint of the hardware resources of the companies. In addition, green software initiatives are still not the priority, despite the influence of software on energy consumption, and in spite of its impact on the environment. Using the set of actions selected, a set of specific actions for software sustainability, to be included in the CSR of software companies, has been defined.  相似文献   

2.
3.
Sexual dimorphism is common in polygynous species, and there is clear evidence that both intra-sexual competition and female preferences can drive the evolution of large body size in males. In contrast, sexual monomorphism is often argued to reflect a relaxation of male mate competition or an intensification of resource competition among females. Alternatively, it might imply opportunities for females to circumvent or counteract male mate competition in a polygynandrous mating system. We test the prediction that sexual monorphism is associated with polygynandry in the collared peccary (Pecari tajacu, Tayassuidae), a social ungulate closely related to the old-world suids. The genetic mating system in the Tayassuidae is unknown, but its sexual monomorphism presents a striking contrast to the strong size dimorphism found in most Suidae, so that a departure from the polygynous system common in Suidae would be noteworthy. We characterized genetic relationships among adults within herds in three geographically distinct populations, assigned parents to 75 offspring, and tested for skew in individual reproductive success. Parentage assignment data indicated that multiple males sire offspring within a herd, and in the population for which genetic data were most complete, 19% of parentage assignments were potentially sired by extra-herd males. Some litters have multiple sires, and neither males nor females monopolized reproduction, even in small herds. This result supports our prediction and suggests that sexual monomorphism may either select for or be an evolutionary consequence of a promiscuous mating system.  相似文献   

4.
• A two-compartment model is able to quantify the effect of nano-TiO2 on Pb toxicity. • Nano-TiO2 reduces Pb tolerance level and increased the killing rate for C. dubia. • Thus, nano-TiO2 synergistically enhances Pb toxicity. • Algae reduce Pb transfer rate to the body tissue and the killing rate. Nano-TiO2 can remarkably increase lead (Pb) toxicity in aquatic organisms. However, the mechanism of this toxicity, additive or synergistic, is not well understood. To explore this mechanism, we inspected the role of nano-TiO2 in the toxicity of Pb on Ceriodaphnia dubia (C. dubia), a model water flea species typically used for ecotoxicity studies. The effect of algae, a diet for aquatic organisms, on the effect of this binary mixture was also investigated. A two-compartment toxicokinetic (TK)-toxicodynamic (TD) modeling approach was used to quantify the Pb toxicity under these complex conditions and to develop critical parameters for understanding the mechanism of toxicity. This two-compartment modeling approach adequately described the Pb accumulation in the gut and in the rest of the body tissue under different nano-TiO2 concentrations, with and without algae, and predicted the toxicity response of C. dubia. It indicated that increasing the nano-TiO2 concentration reduced the Pb tolerance level and concurrently increased the killing rate constant of C. dubia. Therefore, nano-TiO2 synergistically enhanced Pb toxicity. Algae remarkably reduced the toxicity of this binary mixture through reducing the Pb transfer rate to the body tissue and the killing rate, although it did not affect the Pb tolerance level. This two-compartment modeling approach is useful in understanding the role of nanoparticles when assessing the overall toxicity of nanoparticles and other toxic elements in the environment.  相似文献   

5.
Free crawling was an original life style, and the ability to build tubes and bore into shells evolved independently in various annelids and more than once within the family Spionidae. Absence of morphological differences between the shell-boring (SB) and tube-dwelling (TD) spionid worms and the innate ability of borers to build tubes raised a question whether the mode of life is fixed or flexible. Sequence data of three gene fragments of the mitochondrial 16S rDNA and nuclear 18S and 28S rDNA (in total 1,677 bp) have shown that SB and TD individuals of Dipolydora carunculata from the Sea of Japan were genetically identical, whereas those of Polydora triglanda from Taiwan were genetically distant and not conspecific. These data indicate that some species are constrained to a certain mode of life, while others are flexible and individuals can be either SB or TD depending on the place of settlement in the end of their larval development.  相似文献   

6.
In recent years, a number of studies have clearly pointed out the nutritional benefits of fish consumption. However, some concerns about potential health risks derived from contaminants found in fish have also been raised. Therefore, balancing adequately the risks and benefits of fish consumption is currently a health key issue. As tuna fish represents a large part of the traditional food in some countries, the possible impact of tuna fish consumption on public health was investigated. Hepatic damages following consumption of tuna fish white (ordinary) or red (dark) muscle were evaluated in rat. Under our experimental conditions, feeding the animals for 60?days with white or, more markedly, red tuna meat resulted in 1) an elevated uric acid level in blood, 2) an accumulation of lead in liver, 3) an atrophy of liver, 4) an increase in plasma aspartate aminotransferase and alanine aminotransferase activities, and 5) an oxidative stress in liver including an increased level of lipids peroxidation and enhanced activities of superoxide dismutase, catalase and glutathione peroxidase. In addition, liver histology revealed several abnormalities. These alterations could be attributed to both lead accumulation and high purine levels in tuna meat. We conclude that attention should be paid to a possible health impact of frequent and important consumption of tuna fish meat, especially the dark one.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号