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981.
982.
This report shows that the background magnetic field in biological incubators can vary by orders of magnitude within and between incubators. These variations can be observed within the same incubator in locations that are centimeters apart from each other as well as between incubators that are identical and located in the same laboratory. Additionally, the values measured were frequently outside the range of magnitudes found naturally on the Earth's surface or ordinary habitation spaces. Exposure to such altered magnetic field environments has been experimentally shown to be sufficient to cause numerous effects in cell cultures. Examples of the effects reported span from differential generation of free radicals and heat shock proteins to differences in cellular proliferation, differentiation, and death. Although the effects are not well established and the molecular mechanism of action is currently under debate, these observations alone support the notion that the inhomogeneity of the background magnetic field in incubators is a potential confounding source of the variability and reproducibility for studies performed on cell cultures. In this regard, it is recommended that special measures be adopted to control the background magnetic fields in incubators when investigating the biological effects of exposure to magnetic fields of comparable characteristics as the ones measured in this study, or when studying small biological effects in general. Bioelectromagnetics 34:337–348, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
983.
Peter Vandamme Edward R.B. Moore Margo Cnockaert Evie De Brandt Liselott Svensson-Stadler Kurt Houf Theodore Spilker John J. LiPuma 《Systematic and applied microbiology》2013
The phenotypic and genotypic characteristics of fourteen human clinical Achromobacter strains representing four genogroups which were delineated by sequence analysis of nusA, eno, rpoB, gltB, lepA, nuoL and nrdA loci, demonstrated that they represent four novel Achromobacter species. The present study also characterized and provided two additional reference strains for Achromobacter ruhlandii and Achromobacter marplatensis, species for which, thus far, only single strains are publicly available, and further validated the use of 2.1% concatenated nusA, eno, rpoB, gltB, lepA, nuoL and nrdA sequence divergence as a threshold value for species delineation in this genus. Finally, although most Achromobacter species can be distinguished by biochemical characteristics, the present study also highlighted considerable phenotypic intraspecies variability and demonstrated that the type strains may be phenotypically poor representatives of the species. We propose to classify the fourteen human clinical strains as Achromobacter mucicolens sp. nov. (with strain LMG 26685T [=CCUG 61961T] as the type strain), Achromobacter animicus sp. nov. (with strain LMG 26690T [=CCUG 61966T] as the type strain), Achromobacter spiritinus sp. nov. (with strain LMG 26692T [=CCUG 61968T] as the type strain), and Achromobacter pulmonis sp. nov. (with strain LMG 26696T [=CCUG 61972T] as the type strain). 相似文献
984.
Elizabeth Garland Robert J. Gordon 《Visual Anthropology: Published in cooperation with the Commission on Visual Anthropology》2013,26(2-3):267-287
Focusing on tourism ventures that market contact with so‐called bushmen, this paper examines some of the current dynamics and consequences of cultural tourism in Namibia, where the Government has instituted a series of progressive policies to promote local control over tourism development. While notions of primitive cultural otherness continue to feature centrally in tourist demand for contact with “bushmen,” the community‐based and collaborative tourism’ ventures currently being developed in Namibia teach tourists to see their “bushman” hosts as modernizing producers of tourism in their own right, and not just as objects of touristic commodification. Drawing from the anthropological literature on tourism and authenticity, and on the work of Slavoj Zizek on the workings of modern ideology, we argue that such ventures encourage tourists to practise a sort of “meta‐tourism,” in which the authenticity of “traditional bushmen” is replaced by the meta‐authenticity of a tourism experience that thematizes its own effects on the lives of those being visited. For the “bushman” participants in such ventures, we contend, the financial and political benefits of tourism, substantial as they can sometimes be, are ultimately offset by the developmentalist underpinnings of meta‐tourist discourse, which casts “bushmen” as forever not‐quite‐yet fully modern, in perpetual contrast to the tourists who visit them. 相似文献
985.
Previous study of the ear ossicles in Primates has demonstrated that they vary on both functional and phylogenetic bases. Such studies have generally employed two-dimensional linear measurements rather than three-dimensional data. The availability of Ultra- high-resolution X-ray computed tomography (UhrCT) has made it possible to accurately image the ossicles so that broadly accepted methodologies for acquiring and studying morphometric data can be applied. Using UhrCT data also allows for the ossicular chain to be studied in anatomical position, so that it is possible to consider the spatial and size relationships of all three bones. One issue impeding the morphometric study of the ear ossicles is a lack of broadly recognized landmarks. Distinguishing landmarks on the ossicles is difficult in part because there are only two areas of articulation in the ossicular chain, one of which (the malleus/incus articulation) has a complex three-dimensional form. A measurement error study is presented demonstrating that a suite of 16 landmarks can be precisely located on reconstructions of the ossicles from UhrCT data. Estimates of measurement error showed that most landmarks were highly replicable, with an average CV for associated interlandmark distances of less than 3%. The positions of these landmarks are chosen to reflect not only the overall shape of the bones in the chain and their relative positions, but also functional parameters. This study should provide a basis for further examination of the smallest bones in the body in three dimensions. 相似文献
986.
Ross Vander Vorste Mariska Obedzinski Sarah Nossaman Pierce Stephanie M. Carlson Theodore E. Grantham 《Global Change Biology》2020,26(7):3834-3845
Recent droughts raise global concern over potential biodiversity loss and mitigating impacts to vulnerable species has become a management priority. However, drought impacts on populations are difficult to predict, in part, because habitat refuges can buffer organisms from harsh environmental conditions. In a global change context, more extreme droughts may turn previously suitable habitats into ecological traps, where vulnerable species can no longer persist. Here, we explore the impacts of California's recent record‐breaking drought on endangered juvenile Coho salmon. We estimated the variability of cumulative salmon survival using mark–recapture of nearly 20,000 tagged fish in intermittent stream pools during a 7‐year period encompassing drought and non‐drought conditions. We then determined the relative importance of physical habitat, streamflow, precipitation, landscape, and biological characteristics that may limit survival during drought. Our most striking result was an increase in the number of pools with reduced or zero survival during drought years and a coincident increase in spatial variability in survival among study reaches. In nearly half of the stream pools, salmon survival during drought was similar to mean survival of pools assessed during non‐drought years, indicating some pools had remarkable resistance (ability to withstand disturbance) to extreme drought. Lower survival was most attributable to longer duration of disconnection between upstream and downstream habitats, a consequence of increasing drought severity. Our results not only suggest that many pools sustain juvenile salmon in non‐drought years transition into ecological traps during drought but also highlight that some pools serve as refuges even under extreme drought conditions. Projected increases in drought severity that lead to longer droughts and greater habitat fragmentation could transform an increasing proportion of suitable habitats into ecological traps. Predicting future impacts of drought on Coho salmon and other sensitive species will require identification and protection of drought refuges and management strategies that prevent further habitat fragmentation. 相似文献
987.
988.
Huachun Zou Christopher K. Fairley Rebecca Guy Jade Bilardi Catriona S. Bradshaw Suzanne M. Garland Jun Kit Sze Afrizal Afrizal Marcus Y. Chen 《PloS one》2013,8(4)
Background
Guidelines recommend frequent screening of men who have sex with men (MSM) for sexually transmissible infections (STIs) but few interventions have demonstrated increased testing and detection of bacterial STIs among MSM in controlled studies.Methods
We used automated text message and email reminders generated by computer assisted self-interview (CASI) to remind MSM to retest for syphilis. We compared clinic visits, STI testing and detection rates over 12 month between men receiving reminders (reminder group) and men not offered the reminders (concurrent control group).Results
Men who chose 3-monthly reminders had more clinic visits (median 3 vs 1) and higher testing rates for pharyngeal gonorrhoea (67.0% vs 33.6%), rectal gonorrhoea (62.7% vs 31.1%), urethral chlamydia (67.3% vs 39.3%), rectal chlamydia (62.9% vs 31.3%), syphilis (67.0% vs 39.3%) and HIV (64.9% vs 36.7%) (all p<0.001) than concurrent controls, within 12 months after their first visit. Also, men receiving reminders had a higher combined testing rate for all the aforementioned STIs at a same visit (55.7% vs 25.5%, p<0.001) compared with concurrent controls. This association remained after adjusting for differences in characteristics between the two groups (adjusted odds ratio:1.77, 95% confidence interval:1.51-2.08). Men receiving reminders also had a higher detection rate of: rectal gonorrhoea (3.7% vs 1.2%, p = 0.001), urethral chlamydia (3.1% vs 1.4%, p = 0.027), rectal chlamydia (6.6% vs 2.8%, p<0.001), and early, latent syphilis (1.7% vs 0.4%, p = 0.008) compared with concurrent controls.Conclusion
This is the first study to demonstate that a fully automated reminder system using CASI was associated with increased detection of bacterial STIs among MSM. 相似文献989.
990.
Eric K. Hoobler Ganesha Rai Andrew G. S. Warrilow Steven C. Perry Christopher J. Smyrniotis Ajit Jadhav Anton Simeonov Josie E. Parker Diane E. Kelly David J. Maloney S. L. Kelly Theodore R. Holman 《PloS one》2013,8(6)
We report the discovery of a novel dual inhibitor targeting fungal sterol 14α-demethylase (CYP51 or Erg11) and human 5-lipoxygenase (5-LOX) with improved potency against 5-LOX due to its reduction of the iron center by its phenylenediamine core. A series of potent 5-LOX inhibitors containing a phenylenediamine core, were synthesized that exhibit nanomolar potency and >30-fold selectivity against the LOX paralogs, platelet-type 12-human lipoxygenase, reticulocyte 15-human lipoxygenase type-1, and epithelial 15-human lipoxygenase type-2, and >100-fold selectivity against ovine cyclooxygenase-1 and human cyclooxygnease-2. The phenylenediamine core was then translated into the structure of ketoconazole, a highly effective anti-fungal medication for seborrheic dermatitis, to generate a novel compound, ketaminazole. Ketaminazole was found to be a potent dual inhibitor against human 5-LOX (IC50 = 700 nM) and CYP51 (IC50 = 43 nM) in vitro. It was tested in whole blood and found to down-regulate LTB4 synthesis, displaying 45% inhibition at 10 µM. In addition, ketaminazole selectively inhibited yeast CYP51 relative to human CYP51 by 17-fold, which is greater selectivity than that of ketoconazole and could confer a therapeutic advantage. This novel dual anti-fungal/anti-inflammatory inhibitor could potentially have therapeutic uses against fungal infections that have an anti-inflammatory component. 相似文献