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One of the means of creating a more robust methodology for ecological restoration involves reducing the gap between ecological theory and restoration practices. A common strategy to do so is using meta‐analysis to understand key drivers of restoration outcomes. “Active” and “passive” is a dichotomy often used to separate restoration strategies in such meta‐analyses. We investigate previously raised concerns about selection bias and subjective categorization of strategies. We promote a paired experimental design in future empirical research and propose the use of three categories of restoration strategy in lieu of “passive” and “active” to alleviate inconsistency in definitions and categorization. 相似文献
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Lars Grossmann Christina Bock Michael Schweikert Jens Boenigk 《The Journal of eukaryotic microbiology》2016,63(4):419-439
Colourless, nonscaled chrysophytes comprise morphologically similar or even indistinguishable flagellates which are important bacterivors in water and soil crucial for ecosystem functioning. However, phylogenetic analyses indicate a multiple origin of such colourless, nonscaled flagellate lineages. These flagellates are often referred to as “Spumella‐like flagellates” in ecological and biogeographic studies. Although this denomination reflects an assumed polyphyly, it obscures the phylogenetic and taxonomic diversity of this important flagellate group and, thus, hinders progress in lineage‐ and taxon‐specific ecological surveys. The smallest representatives of colourless chrysophytes have been addressed in very few taxonomic studies although they are among the dominant flagellates in field communities. To overcome the blurred picture and set the field for further investigation in biogeography and ecology of the organisms in question, we studied a set of strains of specifically small, colourless, nonscaled chrysomonad flagellates by means of electron microscopy and molecular analyses. They were isolated by a filtration‐acclimatisation approach focusing on flagellates of around 5 μm. We present the phylogenetic position of eight different lineages on both the ordinal and the generic level. Accordingly, we describe the new genera Apoikiospumella, Chromulinospumella, Segregatospumella, Cornospumella and Acrispumella Boenigk et Grossmann n. g. and different species within them. 相似文献
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The transdiagnostic expression of psychotic experiences in common mental disorder (anxiety/depression/substance use disorder) is associated with a poorer prognosis, and a small minority of people may indeed develop a clinical picture that meets criteria for schizophrenia. However, it appears neither useful nor valid to observe early states of multidimensional psychopathology in young people through the “schizo”‐prism, and apply misleadingly simple, unnecessary and inefficient binary concepts of “risk” and “transition”. A review of the “ultra‐high risk” (UHR) or “clinical high risk” (CHR) literature indicates that UHR/CHR samples are highly heterogeneous and represent individuals diagnosed with common mental disorder (anxiety/depression/substance use disorder) and a degree of psychotic experiences. Epidemiological research has shown that psychotic experiences are a (possibly non‐causal) marker of the severity of multidimensional psychopathology, driving poor outcome, yet notions of “risk” and “transition” in UHR/CHR research are restrictively defined on the basis of positive psychotic phenomena alone, ignoring how baseline differences in multidimensional psychopathology may differentially impact course and outcome. The concepts of “risk” and “transition” in UHR/CHR research are measured on the same dimensional scale, yet are used to produce artificial diagnostic shifts. In fact, “transition” in UHR/CHR research occurs mainly as a function of variable sample enrichment strategies rather than the UHR/CHR “criteria” themselves. Furthermore, transition rates in UHR/CHR research are inflated as they do not exclude false positives associated with the natural fluctuation of dimensional expression of psychosis. Biological associations with “transition” thus likely represent false positive findings, as was the initial claim of strong effects of omega‐3 polyunsatured fatty acids in UHR samples. A large body of UHR/CHR intervention research has focused on the questionable outcome of “transition”, which shows lack of correlation with functional outcome. It may be more productive to consider the full range of person‐specific psychopathology in all young individuals who seek help for mental health problems, instead of “policing” youngsters for the transdiagnostic dimension of psychosis. Instead of the relatively inefficient medical high‐risk approach, a public health perspective, focusing on improved access to a low‐stigma, high‐hope, small scale and youth‐specific environment with acceptable language and interventions may represent a more useful and efficient strategy. 相似文献
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M. Gee Chapman 《Restoration Ecology》2012,20(2):277-285
Restoration is important in urban areas where habitat destruction is greatest. It incorporates many levels of intervention, with creation of new habitat the most extreme form. Most research on habitat creation has been terrestrial, or in marine habitats dominated by large structuring biota, such as mangroves. Intertidal boulder‐fields in urban areas are vulnerable to disturbances and habitat loss, which adversely affect numerous habitat specialists. This study describes experiments in which quarried stones were used to create new habitat outside natural boulder‐fields as a practical approach to restoring habitat. Colonization by specialist fauna and by common algae and invertebrates was measured for a year after deployment. Despite sessile assemblages on new boulders differing from those on natural boulders, common and rare animals rapidly colonized the new habitat. There was no clear succession, but colonization was variable and patchy at all scales examined, although diversities and abundances of some species in this novel habitat matched those of natural boulders within a few months. Rare and common animals generally colonized the new habitat as adults moving in from surrounding areas. Creating new boulder‐fields using quarried rocks is a successful approach to restoration and conservation of fauna where natural boulder‐fields are threatened. 相似文献
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Abstract: In algae different types of plastids are known, which vary in pigment content and ultrastructure, providing an opportunity to study their evolutionary origin. One interesting feature is the number of envelope membranes surrounding the plastids. Red algae, green algae and glaucophytes have plastids with two membranes. They are thought to originate from a primary endocytobiosis event, a process in which a prokaryotic cyanobacterium was engulfed by a eukaryotic host cell and transformed into a plastid. Several other algal groups, like euglenophytes and heterokont algae (diatoms, brown algae, etc.), have plastids with three or four surrounding membranes, respectively, probably reflecting the evolution of these organisms by so‐called secondary endocytobiosis, which is the uptake of a eukaryotic alga by a eukaryotic host cell. A prerequisite for the successful establishment of primary or secondary endocytobiosis must be the development of suitable protein targeting machineries to allow the transport of nucleus‐encoded plastid proteins across the various plastid envelope membranes. Here, we discuss the possible evolution of such protein transport systems. We propose that the secretory system of the respective host cell might have been the essential tool to establish protein transport into primary as well as into secondary plastids. 相似文献
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In this review, we focus on strategies for designing functional nano gene carriers, as well as choosing therapeutic genes targeting the tumor microenvironment. Gene mutations have a great impact on the occurrence of cancer. Thus, gene therapy plays a major role in cancer therapy and has the potential to cure cancer. Well‐designed gene therapy largely relies on effective gene carriers, which can be divided into viral carriers and non‐viral carriers. A gene carrier delivers functional genes to their intracellular target and avoids nucleic acids being degraded by nucleases in the serum. Most conventional cancer gene therapies only target cancer cells and do not appear to be sufficintly efficient to pass clinical trials. Accumulating evidence has shown that extending the therapeutic strategies to the tumor microenvironment, rather than the tumor cell itself, can allow more options for achieving robust anti‐cancer efficiency. In addition, unusual features between tumor microenvironment and normal tissues, such as a lower pH, higher glutathione and reactive oxygen species concentrations, and overexpression of some enzymes, facilitate the design of smart stimuli‐responsive gene carriers regulated by the tumor microenvironment. These carriers interact with nucleic acids and then form stable nanoparticles under physiological conditions. By regulation of the tumor microenvironment, stimuli‐responsive gene carriers are able to change their properties and achieve high gene delivery efficiency. Considering the tumor microenvironment as the “regulator” and “target” when designing gene carriers and choosing therapeutic genes shows significant benefit with respect to improving the accuracy and efficiency of cancer gene therapy. 相似文献
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The authors consider that cluster analysis does not objectivize but represents the biologist's subjectivity as to (1) characters considered to be significant and to (2) the way of classification. The latter, however, in authors' opinion, must be specific to the field of application. To this effect some methods are suggested for biology. The methods originate in improvements or transformation of Buser and Baroni-Urbani's method, as well as Watanabe's method, and have the property of processing overall information with no loss or distortion. An agglomerative method which yields a necessarily unique result is suggested, being considered by the authors as a homologue of Watanabe's divisive method. The methods proposed are studied using examples logically constructed. These examples can provide from biology, especially from ecology. 相似文献
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Owen McNamara 《The Australian journal of anthropology》2019,30(3):294-308
In this article I unpack the labour of “networking” to understand the changes in sociality and worker identity that have occurred in the Australian professional managerial class workforce under post‐Fordism. Drawing on fieldwork undertaken at the interface of the pubic service and private consultancy firms in Canberra, I break from dominant readings of intimacy in post‐Fordism which preference either a downwards imposition of “ways of being” from capital to worker, or a reactive self‐regulation in line with objective external structures. Networking, I argue, is as much about being recognised as patron as it is about any tangible economic benefits. The intimate relations and self‐fashioning of networking constitute attempts to embody particular classed, sexualised, gendered fantasies of the figure of “the networker” in post‐Fordist Australian business culture. This interpretation does not necessitate overlooking the tangible results of networking, and I discuss too, how masculine fantasy structures the topography of workplaces. 相似文献
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Like many economic exchanges, industrial symbiosis (IS) is thought to be influenced by social relationships and shared norms among actors in a network. While many implicit references to social characteristics exist throughout the literature, there have been few explicit attempts to operationalize and measure the concepts. The “short mental distance,”“trust,”“openness,” and “communication” recorded among managers in Kalundborg, Denmark, set a precedent for examining and encouraging social interactions among key personnel in the dozens of eco‐industrial networks around the world. In this article we explore the relationships among various aspects of social embeddedness, social capital, and IS. We develop a conceptual framework and an approach using quantitative and qualitative methods to identify and measure these social characteristics, including social network structure, communication, and similarities in norms and conceptions of waste, and apply them in an industrial network in Nanjangud, South India. The findings suggest that there is a fairly high level of shared norms about dealing with waste—the “short mental distance”—in this network, but by‐product transactions are only weakly correlated with the structure and content of communication among managers. Replication of this approach can increase the understanding and comparability of the role of social characteristics in eco‐industrial activities around the world. 相似文献
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George Szmukler 《World psychiatry》2019,18(1):34-41
The United Nations (UN) Convention on the Rights of Persons with Disabilities (CRPD) is the most up‐to‐date international legal instrument concerning the rights of persons with disabilities. Such persons are taken to include those with serious mental disorders. According to an authoritative interpretation of a crucial Article (Article 12 ‐ Equal recognition before the law) by the UN CRPD Committee, involuntary detention and treatment of people with mental health disabilities are prohibited under the Convention. Both conventional mental health law and “capacity‐based” law are deemed to violate the Convention. However, some other UN bodies are not in full agreement (for example, the UN Human Rights Committee and the Subcommittee on Prevention of Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment), while others are less explicitly absolutist (for example, the Human Rights Council). Furthermore, strong criticisms of the position of the CRPD Committee have been mounted from a number of academic quarters. These criticisms center on whether the role of a person's ability to make a decision can be ignored, no matter the circumstances. Much of the above debate turns on the concept of “legal capacity” and the now often‐repeated precept that one must always respect the “will and preferences” of the person with a disability. However, “will and preferences” remains undefined. In this paper, I offer an analysis of “will and preferences” that can clarify interventions that may be acceptable or non‐acceptable under the terms of the UN Convention. 相似文献
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Within the Asteridae (“Sympetalae Tetracyclicae”) two main developmental patterns can be distinguished as regards the formation of corolla tubes, namely “early” and “late sympetaly”. Since the character “ontogeny of sympetaly”, after intensive studies, proved to be valuable for systematic considerations, we now recognize two blocks of orders within the Asteridae (and related groups): the Asteridae A-block and the Asteridae B-block (Figs. 82 and 83). By and large this bipartition referring mainly to the corolla tube development corresponds well with major lineages indentified by recent molecular data (see, e.g., Chase et al., 1993). Asteridae A-block is characterized predominantely by “late sympetaly” the “early sympetaly” in Rubiales and Oleales can be interpreted as derived within this block or can be linked with that in Asteridae B-block. Asteridae B-block is uniform throughout in its “early sympetaly”. In this block it is a primitive character, as judged from its occasional occurrence in the choripetalous Cornales and Apiales (Apiaceae, Araliaceae, Pittosporaceae), which can be regarded as ancestral for block B. 相似文献
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Hanyu Huo Yue Chen Jing Luo Xiaofei Yang Xiangxin Guo Xueliang Sun 《Liver Transplantation》2019,9(17)
Solid polymer electrolytes as one of the promising solid‐state electrolytes have received extensive attention due to their excellent flexibility. However, the issues of lithium (Li) dendrite growth still hinder their practical applications in solid‐state batteries (SSBs). Herein, composite electrolytes from “ceramic‐in‐polymer” (CIP) to “polymer‐in‐ceramic” (PIC) with different sizes of garnet particles are investigated for their effectiveness in dendrite suppression. While the CIP electrolyte with 20 vol% 200 nm Li6.4La3Zr1.4Ta0.6O12 (LLZTO) particles (CIP‐200 nm) exhibits the highest ionic conductivity of 1.6 × 10?4 S cm?1 at 30 °C and excellent flexibility, the PIC electrolyte with 80 vol% 5 µm LLZTO (PIC‐5 µm) shows the highest tensile strength of 12.7 MPa. A sandwich‐type composite electrolyte (SCE) with hierarchical garnet particles (a PIC‐5 µm interlayer sandwiched between two CIP‐200 nm thin layers) is constructed to simultaneously achieve dendrite suppression and excellent interfacial contact with Li metal. The SCE enables highly stable Li plating/stripping cycling for over 400 h at 0.2 mA cm?2 at 30 °C. The LiFePO4/SCE/Li cells also demonstrate excellent cycle performance at room temperature. Fabricating sandwich‐type composite electrolytes with hierarchical filler designs can be an effective strategy to achieve dendrite‐free SSBs with high performance and high safety at room temperature. 相似文献
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M. Michael Gromiha 《Biopolymers》2009,91(7):591-599
In a seminal paper, Pakula and Sauer (Nature, 1990, 344, 363–364) demonstrated that the increase in side‐chain hydrophobicity has a reverse relationship with protein stability. We have addressed this problem with several examples of mutants that span at different locations in protein structure based on secondary structure and solvent accessibility. We confirmed that the stability change upon single coil mutation at exposed region is reversely correlated with hydrophobicity with a single exception. In addition, we found the existence of such relationship in partially buried coil mutants. The stability of exposed helical mutants is governed by conformational properties. In buried and partially buried helical and strand mutants properties reflecting hydrophobicity have direct relationship with stability, whereas an opposite relationship was obtained with entropy and flexibility. The structural analysis of partially buried/exposed mutants showed that the surrounding residues are important for the stability change upon mutation. These results provide insights to understand the general behavior for the stability of proteins upon amino acid substitutions. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 591–599, 2009. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com 相似文献
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Intraspecific variability in the “vowel”‐like sounds of beluga whales (Delphinapterus leucas): Intra‐ and interpopulation comparisons 下载免费PDF全文
Elena M. Panova Roman A. Belikov Alexandr V. Agafonov Olga I. Kirillova Anton D. Chernetsky Vsevolod M. Bel'kovich 《Marine Mammal Science》2016,32(2):452-465
The beluga whale (Delphinapterus leucas) has a rich and complicated vocal repertoire. However, different populations use similar and common types of signals. We studied physical features of one of these types, “vowels,” in three Russian populations: the White Sea population (European North), the Chukotka population (the Bering Sea, Chukotka), and the Okhotsk Sea population (Russian Far East) as well as in four summer aggregations of the White Sea belugas over several years in duration. The pulse repetition rate (PRR) at half of the duration of the signal was measured. We found that the PRR of “vowels” collected in the same summer aggregation during different years is stable in time but varies between locations. The degree of variation corresponds with the geographic distance between different locations. Significant differences were discovered between populations separated by thousands of kilometers, and to a lesser extent, between summer aggregations inhabiting different bays of the White Sea. The variation in PRR between the locations can be caused by the divergence of signals owing to the accumulation of random errors during transmission of these signals from generation to generation, which progressed independently in different summer aggregations and populations. 相似文献
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Thomas M. Butynski Colin A. Chapman Lauren J. Chapman Daniel M. Weary 《American journal of primatology》1992,28(3):183-189
This study examines whether individual adult male blue monkeys (Cercopithecus mitis stuhlmanni) can be identified through acoustic analysis of their “pyow” calls. It is possible to reliably assign the pyow call of the blue monkeys of Kibale Forest, Uganda, to the individual caller based on the acoustic properties of the vocalization. Analysis of pyows made by a recognizable male over a 10-yr period shows that the acoustic properties of one individual's pyow call can remain relatively constant over time. Acoustic analysis of pyow calls may provide a relatively easy and reliable method to document tenure lengths of adult male blue monkeys resident in groups. Similar analyses of the loud calls of other species of primates may, likewise, prove to be useful in documenting long-term membership. © 1992 Wiley-Liss, Inc. 相似文献