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81.
Luiz F L Silveira Gabriel Khattar Stephanie Vaz Vinicius A. Wilson Paula M. Souto José R. M. Mermudes 《Journal of Natural History》2020,54(5-6):275-308
ABSTRACT Fireflies (Coleoptera: Lampyridae) are charismatic insects that have been fruitful model systems in biotechnology. However, lack of information about firefly taxonomy and ecology renders species identification a hard task, especially in the Neotropical region, where fireflies are most diverse. A major gap in the literature on Neotropical fireflies is the lack of knowledge on species’ ecological niches and habitats, which are fundamental aspects for understanding their biology. Here, we provide an annotated checklist of the firefly fauna of the Serra dos Órgãos mountain range (Rio de Janeiro State, Southeastern Brazil), with information on the natural history of each species. We assembled data in three ways: monthly sampling with Malaise traps and active search along an elevational transect from 130 to 2,170 m, over 2 years (2014–2016), extensive field observations, and extracted from historical species records for the Serra dos Órgãos from museum specimens in key collections in Brazil and Europe. We provide a taxonomic key to the genera recorded in the region, and a differential diagnosis for each species, highlighting key references for each taxon. We report 58 species representing 21 genera, making the Serra dos Órgãos one of the richest firefly hotspots on Earth. Most species are restricted to one or two habitat types and/or just one of the regional seasons (warm or cool), and many were only collected either by malaise traps or active search, underlining the importance of sampling different habitat types and seasons, and using different sampling methods when surveying fireflies. Out of the 51 species observed in the field, 49 were active either during the day or the night, although two species – Photuris elliptica and Pyrogaster nigrolineatus – were active in both periods, which is rare in fireflies. 相似文献
82.
83.
Leonardo Vignoli Gabriel Hoinsoudé Segniagbeto Edem A. Eniang Emmanuel Hema Fabio Petrozzi Godfrey C. Akani 《Journal of Natural History》2016,50(11-12):749-758
The ecology of West African arid savannah snakes is still poorly known, especially in regard to the fossorial species. Here, field data on distribution, morphometrics, habitat use and diet are reported for the sand boa Eryx muelleri (Erycidae) from three different countries, i.e. Burkina Faso, Togo and Nigeria. This snake was observed in 21 distinct localities, and a total of 39 individuals was recorded. The species is likely fairly common and locally abundant. Mean body length of snakes was similar among countries and between sexes, but males had proportionately longer tails than females. Body length was significantly positively correlated with both tail length and head length. Adult sex ratio was close to parity. Most of the specimens were found in well-vegetated spots with low percentage of bare soil. There were apparently both ontogenetic and intersexual dietary variations: (1) a single analysed juvenile fed upon a small-sized lizard, whereas adults fed considerably upon young rodents; and (2) females fed exclusively upon young rodents and males upon both lizards and young rodents. In conservation terms, the species is actively exported from Togo for the pet trade, and additional individuals may also be illegally collected in other countries. 相似文献
84.
Takeda Y Costa S Delamarre E Roncal C Leite de Oliveira R Squadrito ML Finisguerra V Deschoemaeker S Bruyère F Wenes M Hamm A Serneels J Magat J Bhattacharyya T Anisimov A Jordan BF Alitalo K Maxwell P Gallez B Zhuang ZW Saito Y Simons M De Palma M Mazzone M 《Nature》2011,479(7371):122-126
PHD2 serves as an oxygen sensor that rescues blood supply by regulating vessel formation and shape in case of oxygen shortage. However, it is unknown whether PHD2 can influence arteriogenesis. Here we studied the role of PHD2 in collateral artery growth by using hindlimb ischaemia as a model, a process that compensates for the lack of blood flow in case of major arterial occlusion. We show that Phd2 (also known as Egln1) haplodeficient (Phd2(+/-)) mice displayed preformed collateral arteries that preserved limb perfusion and prevented tissue necrosis in ischaemia. Improved arteriogenesis in Phd2(+/-) mice was due to an expansion of tissue-resident, M2-like macrophages and their increased release of arteriogenic factors, leading to enhanced smooth muscle cell (SMC) recruitment and growth. Both chronic and acute deletion of one Phd2 allele in macrophages was sufficient to skew their polarization towards a pro-arteriogenic phenotype. Mechanistically, collateral vessel preconditioning relied on the activation of canonical NF-κB pathway in Phd2(+/-) macrophages. These results unravel how PHD2 regulates arteriogenesis and artery homeostasis by controlling a specific differentiation state in macrophages and suggest new treatment options for ischaemic disorders. 相似文献
85.
86.
Enterotypes of the human gut microbiome 总被引:6,自引:0,他引:6
Arumugam M Raes J Pelletier E Le Paslier D Yamada T Mende DR Fernandes GR Tap J Bruls T Batto JM Bertalan M Borruel N Casellas F Fernandez L Gautier L Hansen T Hattori M Hayashi T Kleerebezem M Kurokawa K Leclerc M Levenez F Manichanh C Nielsen HB Nielsen T Pons N Poulain J Qin J Sicheritz-Ponten T Tims S Torrents D Ugarte E Zoetendal EG Wang J Guarner F Pedersen O de Vos WM Brunak S Doré J;MetaHIT Consortium Antolín M Artiguenave F Blottiere HM Almeida M Brechot C Cara C Chervaux C Cultrone A 《Nature》2011,473(7346):174-180
Our knowledge of species and functional composition of the human gut microbiome is rapidly increasing, but it is still based on very few cohorts and little is known about variation across the world. By combining 22 newly sequenced faecal metagenomes of individuals from four countries with previously published data sets, here we identify three robust clusters (referred to as enterotypes hereafter) that are not nation or continent specific. We also confirmed the enterotypes in two published, larger cohorts, indicating that intestinal microbiota variation is generally stratified, not continuous. This indicates further the existence of a limited number of well-balanced host-microbial symbiotic states that might respond differently to diet and drug intake. The enterotypes are mostly driven by species composition, but abundant molecular functions are not necessarily provided by abundant species, highlighting the importance of a functional analysis to understand microbial communities. Although individual host properties such as body mass index, age, or gender cannot explain the observed enterotypes, data-driven marker genes or functional modules can be identified for each of these host properties. For example, twelve genes significantly correlate with age and three functional modules with the body mass index, hinting at a diagnostic potential of microbial markers. 相似文献
87.
88.
This paper presents an algorithmic way of building complex membrane systems by coupling elementary membranes. Its application seems particularly valuable in the case of asynchronous membrane systems, since the resulting membrane system remains asynchronous. The composition method is based on a handshake mechanism implemented by using antiport rules and promoters. 相似文献
89.
Many approaches of business analysis focus on single disciplines or specific problems but ignore complex and dynamic interrelations between small and medium-sized enterprises (SMEs), their stakeholders, and their business environment. In order to meet these challenges, the system analysis tool Vester sensitivity model (VSM) is applied on a reference company representative of the German horticultural retail sector. Based on the principles of system theory and (bio-) cybernetics, the VSM system building tool uses net thinking, heuristics, and a participatory approach to illustrate and evaluate the systemic role of relevant key variables, and their interrelations in the example company. In this article, the analytical steps of the VSM are applied up to the finalized effect system model of the reference company. As an innovative aspect, the article emphasizes how the multilevel process of the system analysis can be put into practice more effectively by using interactive media tools to enable the required communication and consensus by the participating stakeholder panel. Elements such as the manager’s ability of strategic planning, the organizational climate, and the company’s image were uncovered as critical, but also stabilizing key factors for such companies. Although the study focuses on the specific situation of German horticultural retail companies as the research subject, the suggested procedure of integrated knowledge generation is transferrable to any business, industry branch, and country. Especially scholars, advisors, and business analysts working in the field of SME management can use the concept to evaluate such systems in the overall context of the companies under investigation. 相似文献
90.
Kanneganti TD Ozören N Body-Malapel M Amer A Park JH Franchi L Whitfield J Barchet W Colonna M Vandenabeele P Bertin J Coyle A Grant EP Akira S Núñez G 《Nature》2006,440(7081):233-236
Missense mutations in the CIAS1 gene cause three autoinflammatory disorders: familial cold autoinflammatory syndrome, Muckle-Wells syndrome and neonatal-onset multiple-system inflammatory disease. Cryopyrin (also called Nalp3), the product of CIAS1, is a member of the NOD-LRR protein family that has been linked to the activation of intracellular host defence signalling pathways. Cryopyrin forms a multi-protein complex termed 'the inflammasome', which contains the apoptosis-associated speck-like protein (ASC) and caspase-1, and promotes caspase-1 activation and processing of pro-interleukin (IL)-1beta (ref. 4). Here we show the effect of cryopyrin deficiency on inflammasome function and immune responses. Cryopyrin and ASC are essential for caspase-1 activation and IL-1beta and IL-18 production in response to bacterial RNA and the imidazoquinoline compounds R837 and R848. In contrast, secretion of tumour-necrosis factor-alpha and IL-6, as well as activation of NF-kappaB and mitogen-activated protein kinases (MAPKs) were unaffected by cryopyrin deficiency. Furthermore, we show that Toll-like receptors and cryopyrin control the secretion of IL-1beta and IL-18 through different intracellular pathways. These results reveal a critical role for cryopyrin in host defence through bacterial RNA-mediated activation of caspase-1, and provide insights regarding the pathogenesis of autoinflammatory syndromes. 相似文献