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901.
Summary
Rhodomonas sp. was grown in a photo-bioreactor equipped with a measuring cell in a spectrophotometer as part of an external flow loop. The apparent absorbance from 400 to 800 nm of the cell suspension was recorded at predetermined intervals and stored in a computer. From the spectra, the biomass and the concentrations of the two pigments chlorophyll a and phycoerythrin were determined in nitrogen-limited batch cultures. 相似文献
902.
Reusing heat through process integration in heat exchanger networks has long been a key measure for increasing energy efficiency in energy‐intensive industries. Thermal pinch analysis is commonly used for a systematic matching of process streams and thus planning of optimal process integration in large chemical plants. The possible savings increase with the amount of heat and the number of integrated process streams. Therefore co‐ siting of several companies in a symbiotic network opens new opportunities for process integration even in small and medium‐size enterprises (SMEs), but also introduces new challenges. Thermal pinch analysis is extended here to account for piping distances and fluctuations and limited availability of energy flows by adding additional costs for the piping system and a backup utility system in the optimization function. Cooperative game theory is proposed to derive a sharing of savings between the partners of the industrial symbiosis that is optimal for each partner and should prevent partners from leaving the network because of higher benefits in a subgroup or alone. It is argued that knowledge about the optimality of a network for each partner creates trust between the partners that is a necessary base for the long‐term commitment needed in industrial symbioses. An exemplary symbiotic network combining the production of pulp and woody biomass energy carriers is used to illustrate the proposed approaches. 相似文献
903.
A taxonomic reappraisal of the European Daphnia longispina complex (Crustacea, Cladocera, Anomopoda)
Adam Petrusek Anders Hobæk Jens Petter Nilssen Morten Skage Martin ČErný Nora Brede Klaus Schwenk 《Zoologica scripta》2008,37(5):507-519
The Daphnia longispina complex contains some of the most common water flea species in the northern hemisphere, and has been a model organism for many ecological and evolutionary studies. Nevertheless, the systematics and nomenclature of this group, in particular its Palaearctic members, have been in flux for the past 150 years; this hinders the correct interpretation of scientific results and promotes the erroneous use of species names. We revise the systematics of this species complex based on mitochondrial sequence variation (12S rDNA and COI) of representative populations across Europe, with a special focus on samples from type localities of the respective taxa. Combining genetic evidence and morphological assignments of analysed individuals, we propose a comprehensive revision of the European members of the D. longispina complex. We show that D. hyalina and D. rosea morphotypes have evolved several times independently, and we find no evidence to maintain these morphotypes as distinct biological species. Alpine individuals described as D. zschokkei are conspecific with the above-mentioned lineage. We suggest that this morphologically and ecologically plastic but genetically uniform hyalina–rosea–zschokkei clade should be identified as D. longispina (O. F. Müller, 1776). The valid name of Fennoscandian individuals labelled D. longispina sensu stricto in the recent literature is D. lacustris G. O. Sars, 1862. Additionally, we discovered another divergent lineage of this group, likely an undescribed species, in southern Norway. Our results present a solution for several prevailing taxonomic problems in the genus Daphnia , and have broad implications for interpretation of biogeographical patterns, and ecological and evolutionary studies. 相似文献
904.
miRNAs in human subcutaneous adipose tissue: Effects of weight loss induced by hypocaloric diet and exercise 下载免费PDF全文
905.
On the morphology of antennular sensory and attachment organs in cypris larvae of the deep‐sea vent/seep barnacles,Ashinkailepas and Neoverruca 下载免费PDF全文
Takefumi Yorisue Benny K. K. Chan Ryusuke Kado Hiromi Watanabe Koji Inoue Shigeaki Kojima Jens T. Høeg 《Journal of morphology》2016,277(5):594-602
Barnacle cypris larvae show high morphological variation in the organs used in search of and attaching to a substratum. This variation may represent adaptation to the habitat of the species. Here, we studied SEM level morphologies of cypris antennular sensory and attachment organs in a deep‐sea vent endemic species (Neoverruca sp.) and a vent/seep inhabiting species (Ashinkailepas seepiophila). We compare them with three species from other environments. The antennular morphologies of Neoverruca sp. and A. seepiophila were similar, which is consistent with recent molecular studies showing a close relationship of the two species. The setation pattern of the antennules was very conservative among species from various environments. In contrast, striking differences were observed in the structure of the attachment organ (the third antennular segment). Neoverruca sp. and A. seepiophila had no velum or a skirt surrounding the attachment disc on the third segment, while other cirripede cyprids almost always have either of these structures. In addition, both cyprids of A. seepiophila and Neoverruca sp. had the attachment disc angled toward the substratum, whereas it faces distally in cyprids from hard bottom inhabiting barnacles. We suggest that both velum/skirt and the angle of the attachment disc play an important role, when the antennules are contacting the substratum during surface exploration. Differences in attachment organ structures may be highly adaptive, enabling cirripede species to enter new habitats during evolution. J. Morphol. 277:594–602, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
906.
907.
The binding of cardiac glycosides to the E2 conformation of Na, K ATPase suggests that this conformation may represent a potential regulatory site for an endogenous ligand. To examine this hypothesis, delipidated and desalted, ethanolic extracts were prepared from plasma. Plasma extracts produced displacement of 3H-ouabain from Type I and II high affinity binding sites that was parallel to the displacement by cold ouabain. Plasma extracts shifted the binding curve of 3H-ouabain to the right indicating a competitive and reversible displacement. Extracts also produced a dose-dependent inhibition of Na, K ATPase and K-stimulated, p-nitrophenyl phosphatase activity. These results indicate that this ligand may function as an endogenous ligand to the E2 conformation of the Na, K ATPase molecule and be involved in its regulation. 相似文献
908.
Claudia Sengler Julian Zink Jens Klotsche Martina Niewerth Ina Liedmann Gerd Horneff Christoph Kessel Gerd Ganser Angelika Thon Johannes-Peter Haas Anton Hospach Frank Weller-Heinemann Arnd Heiligenhaus Dirk Foell Angela Zink Kirsten Minden 《Arthritis research & therapy》2018,20(1):276
Objective
The objective was to evaluate the 25(OH) vitamin D (25(OH)D) status of patients with juvenile idiopathic arthritis (JIA) and determine whether the 25(OH)D level is associated with disease activity and the course of JIA.Methods
Patients ≤?16?years of age with recently diagnosed JIA (<?12?months) were enrolled in the inception cohort of patients with newly diagnosed JIA (ICON), an ongoing prospective observational, controlled multicenter study started in 2010. Clinical and laboratory parameters were ascertained quarterly during the first year and half-yearly thereafter.Of the 954 enrolled patients, 360 patients with two blood samples taken during the first 2?years after inclusion and with follow up of 3?years were selected. The serum 25(OH)D levels were determined and compared with those of subjects from the general population after matching for age, sex, migration status and the month of blood-drawing.Results
Nearly half of the patients had a deficient 25(OH)D level (<?20?ng/ml) in the first serum sample and a quarter had a deficient level in both samples. Disease activity and the risk of developing JIA-associated uveitis were inversely correlated with the 25(OH)D level (β?=???0.20, 95% CI ??0.37; 0.03, hazard ratio 0.95, 95% CI 0.91; 0.99, respectively).Conclusion
In this study, 25(OH)D deficiency was common and associated with higher disease activity and risk of developing JIA-associated uveitis. Further studies are needed to substantiate these results and determine whether correcting 25(OH)D deficiency is beneficial in JIA.909.
Gradients of disturbance and environmental conditions shape coral community structure for south‐eastern Indian Ocean reefs 下载免费PDF全文
Jens Zinke James P. Gilmour Rebecca Fisher Marji Puotinen Joseph Maina Emily Darling Michael Stat Zoe T. Richards Timothy R. McClanahan Maria Beger Cordelia Moore Nicholas A. J. Graham Ming Feng Jean‐Paul A. Hobbs Scott N. Evans Stuart Field George Shedrawi Russ C. Babcock Shaun K. Wilson 《Diversity & distributions》2018,24(5):605-620
910.
Jens Baumert Christin Heidemann Rebecca Paprott Yong Du Christa Scheidt-Nave 《BMC endocrine disorders》2018,18(1):95