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1.
Insectivorous bats are integral components of terrestrial ecosystems. Despite this, a growing number of factors causing world‐wide declines in bat populations have been identified. Relatively abundant species are important for bat conservation because of their role in ecosystems and the research opportunities they offer. In addition, species that have been well‐studied present unique opportunities to synthesize information and highlight important areas of focus for conservation and research. This paper focuses on a well‐studied abundant bat, Eptesicus fuscus. I review the relevant literature on habitat use, diet and roost selection by E. fuscus in North America, and highlight important areas of conservation and research for this species, including the effects of roost disturbance, control of economically important insect pests, exposure to pesticides, long‐term monitoring of populations, and the potential consequences of expanding populations. These issues have broad implications for other species and can be used to focus future research and conservation efforts.  相似文献   

2.
Oridonin, an active diterpenoid isolated from traditional Chinese herbal medicine, has drawn rising attention for its remarkable apoptosis‐ and autophagy‐inducing activity and relevant molecular mechanisms in cancer therapy. Apoptosis is a well known type of cell death, whereas autophagy can play either pro‐survival or pro‐death roles in cancer cells. Accumulating evidence has recently revealed relationships between apoptosis and autophagy induced by oridonin; however, molecular mechanisms behind them remain to be discovered. In this review, we focus on highlighting updated research on oridonin‐induced cell death signalling pathways implicated in apoptosis and autophagy, in many types of cancer. In addition, we further discuss cross‐talk between apoptosis and autophagy induced by oridonin, in cancer. Taken together, these findings open new perspectives for further exploring oridonin as a potential anti‐tumour agent targeting apoptosis and autophagy, in future anti‐cancer therapeutics.  相似文献   

3.
Signals and cues are fundamental to social interactions. A well‐established concept in the study of animal communication is an amplifier, defined as a trait that does not add extra information to that already present in the original cue or signal, but rather enhances the fidelity with which variation in the original cue or signal is correctly perceived. Attenuators as the logical compliment of amplifiers: attenuators act to reduce the fidelity with which variation in a signal or cue can be reliably evaluated by the perceivers. Where amplifiers reduce the effect of noise on the perception of variation, attenuators add noise. Attenuators have been subject to much less consideration than amplifiers; however, they will be the focus of our theoretical study. We utilize an extension of a well‐established model incorporated signal or cue inaccuracy and costly investments by emitter and perceiver in sending and attending to the signal or cue. We present broad conditions involving some conflict of interest between emitter and perceiver where it may be advantageous for emitters to invest in costly attenuators to mask cues from potential perceivers, and a subset of these conditions where the perceiver may be willing to invest in costly anti‐attenuators to mitigate the loss of information to them. We demonstrate that attenuators can be evolutionary stable even if they are costly, even if they are sometimes disadvantageous and even if a perceiver can mount counter‐measures to them. As such, we feel that attenuators of cues may be deserving of much more research attention.  相似文献   

4.
Despite the importance of a thorough understanding of the effect of synthetic fertiliser on insect population dynamics, existing literature is conflicting and an area of intense debate. Here, a categorical random‐effects meta‐analysis and a vote count meta‐analysis are employed to examine the effects of nitrogen (N), phosphorus (P), potassium (K) and NPK fertiliser on insect population dynamics. In agreement with the general consensus, insects were found to respond positively, overall, to fertilisers. Sucking insects showed a much stronger response to fertilisers than chewing insects. The environment in which a study is conducted can have a marked effect on insect responses to fertiliser, with natural environments showing the potential for buffering effects of nitrogen fertilisers in particular. As well as highlighting the potential shortfall in the amount of research investigating particularly the effects of potassium and phosphorus, this study provides an invaluable flag post in the ongoing research investigating fertiliser effects on ecosystems.  相似文献   

5.
The focus is on a recently developed Yolngu ritual, the memorial or memorial service, which celebrates the lives of Yolngu who have achieved a national reputation. Held before the burial ceremony, the memorial service is orientated ‘both‐ways’ – to the outside as well as to the Yolngu world. Memorial services are analysed in the context of the articulation between Yolngu and the wider Australian society. A diachronically orientated analysis takes into account the longue durée to show how Yolngu create and understand the performance from a historical position and basis of knowledge very different to those of most non‐Yolngu who attend the event. Anthropological research can reveal the durability of local value creation processes that result in very different trajectories of being in an environment of dynamic change.  相似文献   

6.
This article explores the ethnic self‐identification of second‐generation children whose immigrant parents came to the United States from Latin America. The focus of the analysis is the adoption of the pan‐ethnic label, ‘Hispanic’, in contrast to national designators and non‐hyphenated American identities. Using data from a recent large survey of children of immigrants in south Florida and southern California, the analysis explores the determinants of ethnic self‐identities and the potential consequences of the adoption of one of these symbolic labels on children's self‐esteem, educational expectations and perceptions of discrimination. Contrary to the commonly‐held assumption that the label ‘Hispanic’ denotes greater assimilation into the mainstream of US society, our findings indicate that children who adopt the Hispanic label are the least well assimilated: they report poorer English skills, lower self‐esteem and higher rates of poverty than their counterparts who identify themselves as Americans or as hyphenated Americans. Theoretical and policy implications of findings as they bear on prospects for successful adaptation of second‐generation youth are discussed.  相似文献   

7.
Stem cells have been the focus of an intense research due to their potential in Regenerative Medicine, drug discovery, toxicology studies, as well as for fundamental studies on developmental biology and human disease mechanisms. To fully accomplish this potential, the successful application of separation processes for the isolation and purification of stem cells and stem cell‐derived cells is a crucial issue. Although separation methods have been used over the past decades for the isolation and enrichment of hematopoietic stem/progenitor cells for transplantation in hemato‐oncological settings, recent achievements in the stem cell field have created new challenges including the need for novel scalable separation processes with a higher resolution and more cost‐effective. Important examples are the need for high‐resolution methods for the separation of heterogeneous populations of multipotent adult stem cells to study their differential biological features and clinical utility, as well as for the depletion of tumorigenic cells after pluripotent stem cell differentiation. Focusing on these challenges, this review presents a critical assessment of separation processes that have been used in the stem cell field, as well as their current and potential applications. The techniques are grouped according to the fundamental principles that govern cell separation, which are defined by the main physical, biophysical, and affinity properties of cells. A special emphasis is given to novel and promising approaches such as affinity‐based methods that take advantage of the use of new ligands (e.g., aptamers, lectins), as well as to novel biophysical‐based methods requiring no cell labeling and integrated with microscale technologies. Biotechnol. Bioeng. 2012; 109: 2699–2709. © 2012 Wiley Periodicals, Inc.  相似文献   

8.
Tropical reforestation (TR) has been highlighted as an important intervention for climate change mitigation because of its carbon storage potential. TR can also play other frequently overlooked, but significant, roles in helping society and ecosystems adapt to climate variability and change. For example, reforestation can ameliorate climate‐associated impacts of altered hydrological cycles in watersheds, protect coastal areas from increased storms, and provide habitat to reduce the probability of species' extinctions under a changing climate. Consequently, reforestation should be managed with both adaptation and mitigation objectives in mind, so as to maximize synergies among these diverse roles, and to avoid trade‐offs in which the achievement of one goal is detrimental to another. Management of increased forest cover must also incorporate measures for reducing the direct and indirect impacts of changing climate on reforestation itself. Here we advocate a focus on “climate‐smart reforestation,” defined as reforesting for climate change mitigation and adaptation, while ensuring that the direct and indirect impacts of climate change on reforestation are anticipated and minimized.  相似文献   

9.
This review summarises the current knowledge on cryptic species of polychaetes, one of the most dominant taxa in marine communities, and gives a brief overview of the different methods that has been used for their disclosure. Cryptic species constitute an important part of biodiversity and they are common among all kinds of polychaetes, with different life history traits, and may have sympatric as well as allopatric distributions. It is emphasised that cryptic species must not be neglected for a variety of reasons, and even though the magnitude of cryptic species is largely unknown the available data on polychaetes clearly demonstrate that morphology alone seriously underestimate the number of species. It is suggested that future research should focus on appropriately designed case‐studies using combined approaches, as well as on large‐scale whole sample analyses using next‐generation sequencing in order to be able to answer the many questions that still remains.  相似文献   

10.
The Ecological Society of Australia was founded in 1959, and the society’s journal was first published in 1976. To examine how research published in the society’s journal has changed over this time, we used text mining to quantify themes and trends in the body of work published by the Australian Journal of Ecology and Austral Ecology from 1976 to 2019. We used topic models to identify 30 ‘topics’ within 2778 full‐text articles in 246 issues of the journal, followed by mixed modelling to identify topics with above‐average or below‐average popularity in terms of the number of publications or citations that they contain. We found high inter‐decadal turnover in research topics, with an early emphasis on highly specific ecosystems or processes giving way to a modern emphasis on community, spatial and fire ecology, invasive species and statistical modelling. Despite an early focus on Australian research, papers discussing South American ecosystems are now among the fastest‐growing and most frequently cited topics in the journal. Topics that were growing fastest in publication rates were not always the same as those with high citation rates. Our results provide a systematic breakdown of the topics that Austral Ecology authors and editors have chosen to research, publish and cite through time, providing a valuable window into the historical and emerging foci of the journal.  相似文献   

11.
12.
Yield increase: the contribution of plant biotechnology Modern plant breeding is facing increasing challenges to meet future needs caused by global climate changes, decreasing reserves of fossil fuels, an increasing world population as well as an aging society. Therefore, besides input traits, breeding aims focus on renewable resources and to ensure production of sufficient high quality food and feed. In particular, the world‐wide rising in energy demand harbors the risk that more and more agricultural land will be used for industrial purposes instead for food production. Therefore, breeding of highly productive crop plants for the production of valuable biological materials is of great importance. To optimize the production of valuable compounds a profound molecular and biochemical knowledge of the underlying metabolic pathways and the availability of technologies for the transfer of these findings into crop plants are needed. Plant biotechnology can be a key technology being important for deciphering molecular relationships as well as being required for the implementation of these findings into breeding programs.  相似文献   

13.
The rapid increase in worldwide population coupled with the increasing demand for fossil fuels has led to an increased urgency to develop sustainable sources of energy and chemicals from renewable resources. Using microorganisms to produce high‐value chemicals and next‐generation biofuels is one sustainable option and is the focus of much current research. Cyanobacteria are ideal platform organisms for chemical and biofuel production because they can be genetically engineered to produce a broad range of products directly from CO2, H2O, and sunlight, and require minimal nutrient inputs. The purpose of this review is to provide an overview on advances that have been or could be made to improve strains of cyanobacteria for industrial purposes. First, the benefits of using cyanobacteria as a platform for chemical and biofuel production are discussed. Next, an overview of cyanobacterial strain improvements by genetic engineering is provided. Finally, mutagenesis techniques to improve the industrial potential of cyanobacteria are described. Along with providing an overview on various areas of research that are currently being investigated to improve the industrial potential of cyanobacteria, this review aims to elucidate potential targets for future research involving cyanobacteria as an industrial microorganism. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1357–1371, 2016  相似文献   

14.
Cardiac aging     
Health care for the elderly in western society has emerged as an increasingly important economic and political issue in recent years. As the elderly proportion of western populations continues to expand, maintaining health and wellness of the aged will continue to be an important research priority in the near future. This review will attempt to briefly highlight what is known about age-related changes in cardiac performance in humans, then focus on recent work on cellular mechanisms of cardiac deterioration in vertebrate models. The final section will discuss the implications of work done in the nascent fruit fly model system for aging cardiac function and conclude by outlining potential future uses for invertebrate cardiac model systems.  相似文献   

15.
Pain is a major symptom of many diseases and results in enormous pressures on human body or society. Currently, clinically used analgesic drugs, including opioids and nonsteroidal anti‐inflammatory drugs, have adverse reactions, and thus, the development of new types of analgesic drug candidates is urgently needed. Animal venom peptides have proven to have potential as new types of analgesic medicine. In this research, we describe the isolation and characterization of an analgesic peptide from the crude venom of centipede, Scolopendra subspinipes mutilans. The amino acid sequence of this peptide was identical with SsmTX‐I that was previously reported as a specific Kv2.1 ion channel blocker. Our results revealed that SsmTX‐I was produced by posttranslational processing of a 73‐residue prepropeptide. The intramolecular disulfide bridge motifs of SsmTX‐I was Cys1–Cys3 and Cys2–Cys4. Functional assay revealed that SsmTX‐I showed potential analgesic activities in formalin‐induced paw licking, thermal pain, and acetic acid‐induced abdominal writhing mice models. Our research provides the first report of cDNA sequences, disulfide motif, successful synthesis, and analgesic potential of SsmTX‐I for the development of pain‐killing drugs. It indicates that centipede peptide toxins could be a treasure trove for the search of novel analgesic drug candidates. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   

16.
This article focuses on human‐plant relations, drawing on ethnographic research from northern Australia's Gulf Country to address the concept of indigeneity. Just as the identities of ‘Indigenous’ and ‘non‐Indigenous’ people in this region are contextual and at times contested according to the vernacular categories of ‘Blackfellas’, ‘Whitefellas’, and ‘Yellafellas’, so too the issue of what ‘belongs’ in the natural world is negotiated through ambiguities about whether species are useful, productive, and aesthetically pleasing to humans, as well as local understandings about how plants and animals came to be located in the Gulf region. At the same time, plants’ distinctive characteristics as plants shape their relations with humans in ways which affect their categorization as ‘native’ and ‘alien’ or ‘introduced’. Focusing our analysis on three specific trees, we argue that attention to the ‘plantiness’ of flora contributes significantly to debates about indigeneity in society and nature. At the same time, our focus on human‐plant relations contributes important context and nuance to current debates about human and other‐than‐human relations in a more‐than‐human world.  相似文献   

17.
Baculovirus immediate early P35 protein is well known for its anti‐apoptotic as well as anti‐oxidant properties. Mechanism of action of P35 involves inhibition of a vast range of initiator to executioner class of caspases. In addition, P35's role in inhibiting oxidant‐induced mitochondrial damage, primarily in the apoptotic pathway, has also been extensively investigated. Elucidation of P35's functions during regulation of programmed cell death (PCD) has led to a renewed focus on exploiting this basic knowledge for clinical and other related applications. This review outlines specific biochemical and genetic pathways where P35 intervenes and regulates rate‐limiting steps in the apoptotic signaling cascade. Research efforts are underway to utilize P35 as an agent in regulating apoptosis and under certain circumstances, also explore the therapeutic potential of its anti‐oxidant features. One of the major outcomes of recent studies include significantly improved effectiveness of cytochrome P450 directed enzyme pro‐drug delivery tools when used in conjunction with P35, which may help in alleviating drug resistance in tumor cells and simultaneously prolonging the cytotoxic effects of anti‐cancer drugs. Moreover, applied research carried out recently in the fields of diabetes, ischemia‐induced neuronal cell death, experimental autoimmune encephalomyelitis (EAE), multiple sclerosis (MS), inflammatory arthritis, cardiovascular and ocular disorders illustrate P35's utilization across diverse therapeutic areas and will certainly make it an attractive biomolecule for the discovery research. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010  相似文献   

18.
Organic photovoltaic (OPV) solar cells that can be simply processed from solution are in the focus of the academic and industrial community because of their enormous potential to reduce cost. One big challenge in developing a fully solution‐processed OPV technology is the design of a well‐performing electrode system, allowing the replacement of ITO. Several solution‐processed electrode systems were already discussed, but none of them could match the performance of ITO. Here, we report efficient ITO‐free and fully solution‐processed semitransparent inverted organic solar cells based on silver nanowire (AgNW) electrodes. To demonstrate the potential of these AgNW electrodes, they were employed as both the bottom and top electrodes. Record devices achieved fill factors as high as 63.0%, which is comparable to ITO based reference devices. These results provide important progress for fully printed organic solar cells and indicate that ITO‐free, transparent as well as non‐transparent organic solar cells can indeed be fully solution‐processed without losses.  相似文献   

19.
From its discovery as a phosphatidylethanolamine‐binding protein in bovine brain to its designation as a physiological inhibitor of Raf kinase protein, RKIP has emerged as a critical molecule for maintaining subdued, well‐orchestrated cellular responses to stimuli. The disruption of RKIP in a wide range of pathologies, including cancer, Alzheimer's disease, and pancreatitis, makes it an exciting target for individualized therapy and disease‐specific interventions. This review attempts to highlight recent advances in the RKIP field underscoring its potential role as a master modulator of many pivotal intracellular signaling cascades that control cellular growth, motility, apoptosis, genomic integrity, and therapeutic resistance. Specific biological and functional niches are highlighted to focus future research towards an enhanced understanding of the multiple roles of RKIP in health and disease. J. Cell. Physiol. 228: 1688–1702, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

20.
Life‐history traits describe parameters associated with growth, size, survival, and reproduction. Life‐history variation is a hallmark of biological diversity, yet researchers commonly observe that one of the major axes of life‐history variation after controlling for body size involves trade‐offs among growth, reproduction, and longevity. This persistent pattern of covariation among these specific traits has engendered a search for shared mechanisms that could constrain or facilitate production of variation in life‐history strategies. Endocrine traits are one candidate mechanism that may underlie the integration of life history and other phenotypic traits. However, the vast majority of this research has been on the effects of steroid hormones such as glucocorticoids and androgens on life‐history trade‐offs. Here we propose an expansion of the focus on glucocorticoids and gonadal hormones and review the potential role of insulin‐like growth factor‐1 (IGF‐1) in shaping the adaptive integration of multiple life‐history traits. IGF‐1 is a polypeptide metabolic hormone largely produced by the liver. We summarize a vast array of research demonstrating that IGF‐1 levels are susceptible to environmental variation and that IGF‐1 can have potent stimulatory effects on somatic growth and reproduction but decrease lifespan. We review the few studies in natural populations that have measured plasma IGF‐1 concentrations and its associations with life‐history traits or other characteristics of the organism or its environment. We focus on two case studies that found support for the hypothesis that IGF‐1 mediates adaptive divergence in suites of life‐history traits in response to varying ecological conditions or artificial selection. We also examine what we view as potentially fruitful avenues of research on this topic, which until now has been rarely investigated by evolutionary ecologists. We discuss how IGF‐1 may facilitate adaptive plasticity in life‐history strategies in response to early environmental conditions and also how selection on loci controlling IGF‐1 signaling may mediate population divergence and eventual speciation. After consideration of the interactions among androgens, glucocorticoids, and IGF‐1 we suggest that IGF‐1 be considered a suitable candidate mechanism for mediating life‐history traits. Finally, we discuss what we can learn about IGF‐1 from studies in free‐ranging animals. The voluminous literature in laboratory and domesticated animals documenting relationships among IGF‐1, growth, reproduction, and lifespan demonstrates the potential for a number of new research questions to be asked in free‐ranging animals. Examining how IGF‐1 mediates life‐history traits in free‐ranging animals could lead to great insight into the mechanisms that influence life‐history variation.  相似文献   

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