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91.

Background, aim, and scope

Methodology development should reflect demands from the intended users: what are the needs of the user group and what is feasible in terms of requirements involving data and work? Mapping these questions of relevance and feasibility is thus a way to facilitate a higher degree of relevance of the developed methodology. For the emerging area of social life cycle assessment (SLCA), several different potential user groups may be identified. This article addresses the issues of relevance and feasibility of SLCA from a company perspective through a series of interviews among potential company users.

Methods and materials

The empirical basis for the survey is a series of eight semi-structured interviews with larger Danish companies, all of which potentially have the capacity and will to use comprehensive social assessment methodologies. SLCA is not yet a well-defined methodology, but still it is possible to outline several potential applications of SLCA and the tasks a company must be able to perform in order to make use of these applications. The interviews focus on the companies’ interest in these potential applications and their ability and willingness to undertake the required work.

Results

Based on these interviews, three hypotheses are developed relating to these companies’ potential use of SLCA, viz.: (1) needs which may be supported by SLCA relate to three different applications, being comparative assertions, use stage assessments, and weighting of social impacts; (2) assessing the full life cycle of a product or service is rarely possible for the companies; and (3) companies see their social responsibility in the product chain as broader than dictated by the product perspective of SLCA. Trends for these three hypotheses developed on the basis of the opinions of the interviewees. Also, factors influencing the generalization of the results to cover other industries are analyzed.

Discussion

Full comparative assertions as known from environmental life cycle assessment (LCA) may be difficult in a company context due to several difficulties in assessing the full life cycle. Furthermore, the comparative assertion may potentially be hampered by differences in how companies typically allocate responsibility along the product chain and how it is done in SLCA, creating a boundary setting issue. These problems do, only in a limited degree, apply for both the use stage assessment and the tool for weighting social issues.

Conclusion

Despite these difficulties, it is concluded that all three applications of SLCA may be possible for the interviewed companies, but it seems the tendency is to demand assessment tools with very limited life cycle perspective, which to some extent deviate from the original thought behind the LCA tools as being holistic decision aid tools.

Perspectives

It is advocated that there is a need to focus more on questions regarding the relevance and feasibility of SLCA from several different perspectives to direct the future methodology development.  相似文献   
92.
The genomic organization and chromosomal location of theβ-tubulin isogenes inLeishmania donovani promastigotes has been studied by nucleic acid hybridization techniques using a cloned β-tubulin gene. We have cloned aβ-tubulin gene fragment, 3.3 kbp long, from genomic DNA ofLeishmania donovani using a heterologousβ-tubulin DNA as probe. Restriction maps of this clone have been prepared. It has been estimated that there are approximately 11–15 copies of theβ-tubulin genes per haploid genome. The majority of these isogenes are arranged in a tandem repeat with a length of 3.5 kbp on a single chromosome. In addition a few dispersed gene copies at different chromosomal loci were detected by pulse field gradient gel electrophoresis. Part of the internal coding region of the gene has been sequenced to confirm the identity of theβ-tubulin clone and is found to be nearly identical to that ofLeishmania mexicana amazonensis.  相似文献   
93.
Compared to younger adults, seniors (≥60 yrs) often adopt a highly regular lifestyle, perhaps as an adaptive response to age‐related changes in their sleep and circadian rhythms. At baseline, diary measures of lifestyle regularity (SRM‐5) were obtained from 104 seniors of three separate groups. Thirty‐three subjects were challenged by spousal bereavement or the need to care for a spouse at home with dementia (Challenged); 33 were suffering from formally diagnosed (DSM‐IV) insomnia (Insomnia); and 38 were healthy, well‐functioning older seniors in the second half of their eighth decade of life or later (Healthy Older). The objective of this study was to determine whether lifestyle regularity increased as a function of age within each of these three senior groups. Overall, age was significantly correlated with SRM‐5 (r=0.41, p<0.001), with the SRM score increasing by 0.67 units/decade. The same was true for the Challenged and Insomnia groups, which also showed a significant correlation between SRM and age (Challenged: r=0.48, p<0.01; Insomnia: r=0.36, p<0.05), though with a slightly faster rate of SRM increase in the Challenged (0.95 units/decade) than Insomnia (0.55 units/decade) group. Perhaps there was no correlation between age and SRM (r=0.07, n.s.) in the Healthy Older group due to the small age range, although this group did have a higher overall SRM score than the other two groups (p<0.01). The study thus confirmed that the previously observed increase in lifestyle regularity over the adult lifespan persists into later life. This may represent an adaptive behavioral response that might be used in future therapeutic approaches.  相似文献   
94.
Egg activation is the essential process in which mature oocytes gain the competency to proceed into embryonic development. Many events of egg activation are conserved, including an initial rise of intracellular calcium. In some species, such as echinoderms and mammals, changes in the actin cytoskeleton occur around the time of fertilization and egg activation. However, the interplay between calcium and actin during egg activation remains unclear. Here, we use imaging, genetics, pharmacological treatment, and physical manipulation to elucidate the relationship between calcium and actin in living Drosophila eggs. We show that, before egg activation, actin is smoothly distributed between ridges in the cortex of the dehydrated mature oocytes. At the onset of egg activation, we observe actin spreading out as the egg swells though the intake of fluid. We show that a relaxed actin cytoskeleton is required for the intracellular rise of calcium to initiate and propagate. Once the swelling is complete and the calcium wave is traversing the egg, it leads to a reorganization of actin in a wavelike manner. After the calcium wave, the actin cytoskeleton has an even distribution of foci at the cortex. Together, our data show that calcium resets the actin cytoskeleton at egg activation, a model that we propose to be likely conserved in other species.  相似文献   
95.
The nautilus, commonly known as a “living fossil,” is endangered and may be at risk of extinction. The lack of genomic information hinders a thorough understanding of its biology and evolution, which can shed light on the conservation of this endangered species. Here, we report the first high-quality chromosome-level genome assembly of Nautilus pompilius. The assembled genome size comprised 785.15 Mb. Comparative genomic analyses indicated that transposable elements (TEs) and large-scale genome reorganizations may have driven lineage-specific evolution in the cephalopods. Remarkably, evolving conserved genes and recent TE insertion activities were identified in N. pompilius, and we speculate that these findings reflect the strong adaptability and long-term survival of the nautilus. We also identified gene families that are potentially responsible for specific adaptation and evolution events. Our study provides unprecedented insights into the specialized biology and evolution of N. pompilius, and the results serve as an important resource for future conservation genomics of the nautilus and closely related species.  相似文献   
96.
Animal communication often involves multimodal signals, and interactions between sensory modalities can trigger unique responses in receivers. Response to social signals was investigated in fire-bellied toads by exposing them to playback of male calls (advertisement and release calls) and a video clip of a male conspecific in the laboratory. The cues were presented in isolation and as a combined bimodal stimulus, and approach frequency, latency to approach and time spent around the stimulus source were measured. No positive phonotaxis was observed toward the advertisement call, both during the day and during a phonotaxis trial performed at night. However, females, but not males, approached with greater frequency, lower latency, and spent more time near the source of the bimodal stimulus in an experiment involving the advertisement call. Female response was specific to the advertisement call, as approach was not increased when the release call was used. Males, on the other hand, did not show increased approach in the advertisement call experiment, but approached with greater frequency the bimodal stimulus involving the release call within the first minute of stimulus presentation. The findings suggest that females orient toward calling males and that males eavesdrop on release calls, but in both cases a visual stimulus is also needed to trigger a response. Social approach in Bombina orientalis is thus dependent on multisensory cues, and the nature of the interaction between sensory modalities depends on receiver sex and call type.  相似文献   
97.
98.
群居性动物的幼仔对亲本的识别有利于获得最大化的亲本抚育。雄性棕色田鼠对幼仔具有较高水平的父本投资,那么幼仔在断乳前是否能够识别父鼠并形成条件位置偏爱(Conditioned place preference,CPP)呢?本研究通过双向选择测试、社会互作测试以及CPP 测试探讨了这一问题。双向选择结果显示,与陌生雄鼠相比,出生后14 d 和21 d 的幼仔对父鼠访问的持续时间及潜伏期有显著性差异(P < 0.05);社会互作结果表明,14 d幼仔对父鼠的跟随行为较陌生雄鼠多,但探究行为及亲密行为没有显著性差异(P > 0.05),21 d 幼仔对父鼠的探究行为较少、跟随行为和亲密行为较多(P < 0.05)。CPP 结果表明,在连续4 d (出生后13 ~ 16 d;19 ~ 22 d)的父鼠强化后,第17 d 和第23 d 的幼仔不能形成对父鼠的位置偏爱(P > 0.05)。这些结果说明断乳前的棕色田鼠幼仔已能够识别父鼠和陌生雄鼠,但不能形成对父鼠的位置偏爱。  相似文献   
99.
Approximately 43–60% of the total genome in bovine, goat and sheep consisted of interspersed repeated and single copy DNA sequences. Most of the interspersed repeated DNA sequences were 1500–2400 nucleotide pair long while a minor portion was more than 4000 nucleotide pair long in goat and sheep and 3200 nucleotide pair long in bovine. About 1/3rd of single copy sequence were interspersed and their length was in the range of 1000–1500 nucleotide pairs.  相似文献   
100.
Summary The major families of repeated DNA sequences in the genome of tomato (Lycopersicon esculentum) were isolated from a sheared DNA library. One thousand clones, representing one million base pairs, or 0.15% of the genome, were surveyed for repeated DNA sequences by hybridization to total nuclear DNA. Four major repeat classes were identified and characterized with respect to copy number, chromosomal localization by in situ hybridization, and evolution in the family Solanaceae. The most highly repeated sequence, with approximately 77000 copies, consists of a 162 bp tandemly repeated satellite DNA. This repeat is clustered at or near the telomeres of most chromosomes and also at the centromeres and interstitial sites of a few chromosomes. Another family of tandemly repeated sequences consists of the genes coding for the 45 S ribosomal RNA. The 9.1 kb repeating unit in L. esculentum was estimated to be present in approximately 2300 copies. The single locus, previously mapped using restriction fragment length polymorphisms, was shown by in situ hybridization as a very intense signal at the end of chromosome 2. The third family of repeated sequences was interspersed throughout nearly all chromosomes with an average of 133 kb between elements. The total copy number in the genome is approximately 4200. The fourth class consists of another interspersed repeat showing clustering at or near the centromeres in several chromosomes. This repeat had a copy number of approximately 2100. Sequences homologous to the 45 S ribosomal DNA showed cross-hybridization to DNA from all solanaceous species examined including potato, Datura, Petunia, tobacco and pepper. In contrast, with the exception of one class of interspersed repeats which is present in potato, all other repetitive sequences appear to be limited to the crossing-range of tomato. These results, along with those from a companion paper (Zamir and Tanksley 1988), indicate that tomato possesses few highly repetitive DNA sequences and those that do exist are evolving at a rate higher than most other genomic sequences.  相似文献   
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