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21.
Ron Macnab 《Ocean Development & International Law》2013,44(2):223-234
Submarine elevations and ridges present an array of definitional uncertainties to coastal states that are engaged in the high-stakes process of delimiting extended continental shelves. Faced with the imprecise terminology of Article 76, with the nonspecific wording of the Scientific and Technical Guidelines of the Commission on the Limits of the Continental Shelf (CLCS), and with the Commission's rules of confidentiality that hamper the open exchange of information concerning ridge and elevation assessments in previous continental shelf implementations, a coastal state needs to develop its own evaluations of what might and might not pass the “test of appurtenance.” Significant components of a continental shelf submission might thus be formulated on the basis of these national evaluations, only to have the CLCS question them, which could necessitate a potentially expensive and time-consuming reworking of the submission. This article outlines the ramifications of this wild card effect. 相似文献
22.
Denise Montgomery 《Arts Education Policy Review》2017,118(1):1-18
ABSTRACTCreative youth development (CYD) is a dynamic area of community arts education that successfully bridges youth development and arts education. CYD is an intentional, holistic practice that combines hands-on artmaking and skill building in the arts with development of life skills to support young people in successfully participating in adolescence and navigating into adulthood. Young people in CYD programs exhibit high levels of artistic skill and accomplishment along with increased self-esteem and sense of belonging. CYD participants are immersed in a broad array of rigorous artistic endeavors, including creating documentary films, researching and reporting on community issues through radio broadcasts, writing and staging new theatrical works, and engaging in thoughtful critique of one another's visual art work. The impact for youth of program participation extends beyond pride in artistic accomplishment. Throughout the United States, teen participants in CYD programs assert that the programs saved their lives, putting them on positive trajectories and away from gangs, drug use, crime, and ennui. This article provides a definition for the term creative youth development, describes core characteristics of CYD programs, and briefly describes four CYD programs. It provides background on the origins and history of creative youth development, including current advances in the field and signs the field is coalescing. The article describes creative youth development in the larger contexts of arts education and of education reform. Lastly, the article discusses policy, funding, and research needs and opportunities and provides questions for consideration. 相似文献
23.
L-Lactate cytochrome c oxidoreductase (flavocytochrome b 2, FC b 2) from the thermotolerant methylotrophic yeast Hansenula polymorpha (Pichia angusta) is, unlike the enzyme form baker’s yeast, a thermostable enzyme potentially important for bioanalytical technologies for highly selective assays of L-lactate in biological fluids and foods. This paper describes the construction of flavocytochrome b 2 producers with over-expression of the H. polymorpha CYB2 gene, encoding FC b 2. The HpCYB2 gene under the control of the strong H. polymorpha alcohol oxidase promoter in a plasmid for multicopy integration was transformed into the recipient strain H. polymorpha C-105 (grc1 catX), impaired in glucose repression and devoid of catalase activity. A method was developed for preliminary screening of the transformants with increased FC b 2 activity in permeabilized yeast cells. The optimal cultivation conditions providing for the maximal yield of the target enzyme were found. The constructed strain is a promising FC b 2 producer characterized by a sixfold increased (to 3 μmol min?1 mg?1 protein in cell-free extract) activity of the enzyme. 相似文献
24.
Jeffrey A. Harvey Daniela Weber Patrick De Clercq Rieta Gols 《Entomologia Experimentalis et Applicata》2013,149(3):219-228
In some parasitic Hymenoptera the dying caterpillars remain attached or close to the parasitoid cocoons. It has been suggested that the caterpillars act as ‘bodyguards’ for the vulnerable cocoons and therefore protect them against predators and/or hyperparasitoids (the ‘usurpation hypothesis’). This hypothesis has been demonstrated in associations where the caterpillars remain active and/or aggressive after parasitism. However, in other associations the caterpillars are so physiologically depleted after parasitism that they are unable to physically defend the cocoons and instead sit atop them in a moribund state. In this study a generalist predator, the spined soldier bug, Podisus maculiventris Say (Hemiptera: Pentatomidae), was provided with cocoons of the gregarious endoparasitoid Cotesia glomerata L. and the solitary endoparasitoid Microplitis mediator Haliday (both Hymenoptera: Braconidae), in turn attended by their hosts, Pieris brassicae L. (Lepidoptera: Pieridae) and Mamestra brassicae L. (Lepidoptera: Noctuidae), respectively. Cotesia glomerata produces broods of up to 40 cocoons and the dying caterpillars sit atop the cocoons where they exhibit little response to physical stimuli. Previous studies reported that dying P. brassicae caterpillars were ineffective bodyguards against two species of hyperparasitoids. In both associations, the dying host caterpillars were significantly preferred as food by P. maculiventris over the parasitoid cocoons. However, in absence of caterpillars, the bugs readily attacked the C. glomerata cocoons. Alternatively, the survival of M. mediator was very low, irrespective of whether a caterpillar was present or not. Caterpillars attacked by M. mediator are several times smaller than those attacked by C. glomerata. Consequently, the predators ran out of food much more quickly in the former and switched from one prey to the other. We show that in some host–parasitoid associations the dying caterpillars provide more visually apparent or nutritionally superior prey, rather than acting as bodyguards. 相似文献
25.
Ke Wang Jiayu Wang Klaus Hubacek Zhifu Mi Yi‐Ming Wei 《Journal of Industrial Ecology》2020,24(3):564-576
China's high‐speed economic development and reliance on overconsumption of natural resources have led to serious environmental pollution. Environmental taxation is seen as an effective economic tool to help mitigate air pollution. In order to assess the effects of different scenarios of environmental taxation policies, we propose a frontier‐based environmentally extended input–output optimization model with explicit emission abatement sectors to reflect the inputs and benefits of abatement. Frontier analysis ensures policy scenarios are assessed under the same technical efficiency benchmark, while input–output analysis depicts the wide range of economic transactions among sectors of an economy. Four scenarios are considered in this study, which are increasing specific tax rates of SO2, NOx, and soot and dust separately and increasing all three tax rates simultaneously. Our estimation results show that: raising tax rates of SO2, NOx, and soot and dust simultaneously would have the highest emission reduction effects, with the SO2 tax rate making the greatest contribution to emission reduction. Raising the soot and dust tax rate is the most environmentally friendly strategy due to its highest abatement to welfare through avoided health costs. The combination of frontier analysis and input–output analysis provides policy makers a comprehensive and sectoral approach to assess costs and benefits of environmental taxation. 相似文献
26.
27.
Chris L. Schürmann Jan A. R. A. M. van Hooff 《International journal of primatology》1986,7(3):265-287
Recent field data indicate that MacKinnon’s model of the orang-utan’s sexual and agonistic activity needs to be revised. In
this model, male reproductive activity is concentrated in an extended phase of subadulthood and in early adulthood. According
to this model, the role of older adult males is primarily that of range guardian, and in that role they would ensure that
the offspring they had generated earlier would have safe access to food resources. This study presents cases suggesting that
subadult males, even though sexually active, may have low reproductive success. In previous studies adult males were shown
to display less sexual initiative than subadult males. In this study an adult male was at times involved infrequent mating
activity in response to proceptive activity of females in the course of consortship. This adult male proved to be a successful
breeder, thus refuting the hypothesis of adult male sterility. The female is most likely to conceive through cooperative mating
in lengthy consortships with the dominant resident adult male. We hypothesize that the extended subadult phase represents
a submissive strategy, allowing subadult males to remain in the home range of adult males but with minimal reproductive success. 相似文献
28.
T. Reed Miller Peter Berrill Paul Wolfram Ranran Wang Yookyung Kim Xinzhu Zheng Edgar G. Hertwich 《Journal of Industrial Ecology》2019,23(6):1410-1424
Each year businesses, governments, and homeowners in the United States invest around one fifth of gross domestic product into the creation of capital assets such as buildings, machinery, and software to enable production and consumption. Use of capital is typically included to some extent in environmental life cycle assessments of goods and services but is not incorporated into most environmentally extended input‐output (EEIO) models, including the US Environmental Protection Agency's USEEIO. Capital assets are typically created in years prior to their use, so a challenge lies in distributing the impacts of their creation over time. In this work, a highly detailed capital flow matrix approach is followed to distribute the use of fixed capital assets to consuming industries. Data from the US Bureau of Economic Analysis's Fixed Asset Accounts is merged with its Industry Accounts data by the creation of concordance tables. Public highways and streets are partially reallocated to industries operating vehicles. The resulting capital use matrix is later combined into a modified USEEIO. “Housing” is found to be the largest consumer of fixed assets, followed by general government, fossil fuel extraction, and financial industries involved in leasing. Construction, vehicles, and machinery are mostly used by industries in the form of fixed assets. The types of fixed assets used by industries are consistent with expectations: housing is dominated by structures, transport by equipment, and information industries by intellectual property products. 相似文献
29.
André Franz Leena Ackermann Thorsten Hoppe 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2014
The AAA-ATPase Cdc48 (also called p97 or VCP) acts as a key regulator in proteolytic pathways, coordinating recruitment and targeting of substrate proteins to the 26S proteasome or lysosomal degradation. However, in contrast to the well-known function in ubiquitin-dependent cellular processes, the physiological relevance of Cdc48 in organismic development and maintenance of protein homeostasis is less understood. Therefore, studies on multicellular model organisms help to decipher how Cdc48-dependent proteolysis is regulated in time and space to meet developmental requirements. Given the importance of developmental regulation and tissue maintenance, defects in Cdc48 activity have been linked to several human pathologies including protein aggregation diseases. Thus, addressing the underlying disease mechanisms not only contributes to our understanding on the organism-wide function of Cdc48 but also facilitates the design of specific medical therapies. In this review, we will portray the role of Cdc48 in the context of multicellular organisms, pointing out its importance for developmental processes, tissue surveillance, and disease prevention. This article is part of a Special Issue entitled: Ubiquitin–Proteasome System. Guest Editors: Thomas Sommer and Dieter H. Wolf. 相似文献
30.
Frithjof C. Küpper Catherine Leblanc Wolfram Meyer‐Klaucke Philippe Potin Martin C. Feiters 《Journal of phycology》2014,50(4):652-664
Members of various algal lineages are known to be strong producers of atmospherically relevant halogen emissions, that is a consequence of their capability to store and metabolize halogens. This study uses a noninvasive, synchrotron‐based technique, X‐ray absorption spectroscopy, for addressing in vivo bromine speciation in the brown algae Ectocarpus siliculosus, Ascophyllum nodosum, and Fucus serratus, the red algae Gracilaria dura, G. gracilis, Chondrus crispus, Osmundea pinnatifida, Asparagopsis armata, Polysiphonia elongata, and Corallina officinalis, the diatom Thalassiosira rotula, the dinoflagellate Lingulodinium polyedrum and a natural phytoplankton sample. The results highlight a diversity of fundamentally different bromine storage modes: while most of the stramenopile representatives and the dinoflagellate store mostly bromide, there is evidence for Br incorporated in nonaromatic hydrocarbons in Thalassiosira. Red algae operate various organic bromine stores – including a possible precursor (by the haloform reaction) for bromoform in Asparagopsis and aromatically bound Br in Polysiphonia and Corallina. Large fractions of the bromine in the red algae G. dura and C. crispus and the brown alga F. serratus are present as Br? defects in solid KCl, similar to what was reported earlier for Laminaria parts. These results are discussed according to different defensive strategies that are used within algal taxa to cope with biotic or abiotic stresses. 相似文献