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Astronomische Nachrichten, nos 2869-2875
No full textR. R. Astronomische Nachrichten, nos 2869-2875. In: Bulletin astronomique, tome 6, 1889. pp. 178-184
Vertical structure and kinematics of tropical monsoon precipitation observed from a 2875-MHz profiler during NAME
No full textFall 2006.Includes bibliographical references (pages 100-105).Deep cloud systems in the Tropics play a significant role in the global heat budget. This is due to the fact that atmospheric circulations, such as the Hadley and Walker cells, are sensitive to the shape of the diabatic heating profile, which in turn depends on the vertical structure of tropical convective systems. The goal of this project is to create a climatology of the vertical structure of precipitating cloud systems that characterized the 2004 North American monsoon. The study utilized data from the 2875-MHz profiler stationed near Sinaloa, Mexico from early July through mid-September of 2004 for the North American Monsoon Experiment (NAME). The profiler observed 23 rain events. Climatologic frequency distributions of reflectivity, Doppler velocity, and spectral width were created for various precipitation regimes. The NAME distributions compared favorably with results from previous studies. Stratiform precipitation exhibited a radar bright band and a strong Doppler velocity gradient in the melting layer, and weak spectral width above the melting layer. Mixed stratiform/convective regions contained low reflectivity and a weak bright band. Convective profiles contained high reflectivity, large Doppler velocities, and high spectral width. Vertical air motions derived from the 2875-MHz profiler were compared with EVAD and 449-MHz profiler retrievals. The 2875-MHz pro filer vertical air motion estimates contained a negative bias to both methods of approximately 0.5 m s-1. Though the errors in the stratiform vertical air motion estimates were of the same order as the stratiform air motions, the NAME vertical air motion composites for stratiform and mixed stratiform/convective precipitation exhibited similar features to composites from previous studies. However, convective composites from past studies showed ascent throughout the troposphere while the NAME composite showed a significant region of descent between 4 and 6 km. This discrepancy cannot be fully explained by the negative bias of 0.5 m s-1 in the NAME estimates. Climatologic vertical profiles of precipitating clouds were successfully created from the 2875-MHz pro filer NAME dataset for various precipitation regimes. While the vertical air motion estimates yielded unexpected values in the melting layer of convective precipitation, they proved useful in analyzing the vertical structure of vertical air motion for various precipitation regimes in a mean sense as well as assessing general updraft and downdraft intensity in individual convective cells
Target product profiles for protecting against outdoor malaria transmission.
No full textBACKGROUND\ud
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Long-lasting insecticidal nets (LLINs) and indoor residual sprays (IRS) have decimated malaria transmission by killing indoor-feeding mosquitoes. However, complete elimination of malaria transmission with these proven methods is confounded by vectors that evade pesticide contact by feeding outdoors.\ud
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METHODS\ud
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For any assumed level of indoor coverage and personal protective efficacy with insecticidal products, process-explicit malaria transmission models suggest that insecticides that repel mosquitoes will achieve less impact upon transmission than those that kill them outright. Here such models are extended to explore how outdoor use of products containing either contact toxins or spatial repellents might augment or attenuate impact of high indoor coverage of LLINs relying primarily upon contact toxicity.\ud
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RESULTS\ud
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LLIN impact could be dramatically enhanced by high coverage with spatial repellents conferring near-complete personal protection, but only if combined indoor use of both measures can be avoided where vectors persist that prefer feeding indoors upon humans. While very high levels of coverage and efficacy will be required for spatial repellents to substantially augment the impact of LLINs or IRS, these ambitious targets may well be at least as practically achievable as the lower requirements for equivalent impact using contact insecticides.\ud
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CONCLUSIONS\ud
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Vapour-phase repellents may be more acceptable, practical and effective than contact insecticides for preventing outdoor malaria transmission because they need not be applied to skin or clothing and may protect multiple occupants of spaces outside of treatable structures such as nets or houses
Telegram re: Bill 2875 and Bill 1281
No full textLetter from Amon G. Carter to Sam Rayburn, Speaker of the House of Representatives, regarding Bill 2875 and Bill 1281
Block Card 2875 Nash Road
No full textThis image was produced by the Auditor's Office in Lucas County, Ohio for tax assessment purposes. Associated dates are approximate. Descriptive terms related to this photograph include: Dwelling | 2875 Nash Road (Toledo, Ohio) | Cape Cod Style | Boyville (Toledo, Ohio) | Deveaux Area (Toledo, Ohio) | West Toledo area (Toledo, Ohio
Telegram re: S. 2875, Extension Air Port Act
No full textTelegram from Lyndon B. Johnson to Amon G. Carter re: the Senate adopting S. 2875, Extension Air Port Ac
Assessing agreement between malaria slide density readings.
No full textBACKGROUND: Several criteria have been used to assess agreement between replicate slide readings of malaria parasite density. Such criteria may be based on percent difference, or absolute difference, or a combination. Neither the rationale for choosing between these types of criteria, nor that for choosing the magnitude of difference which defines acceptable agreement, are clear. The current paper seeks a procedure which avoids the disadvantages of these current options and whose parameter values are more clearly justified. METHODS AND RESULTS: Variation of parasite density within a slide is expected, even when it has been prepared from a homogeneous sample. This places lower limits on sensitivity and observer agreement, quantified by the Poisson distribution. This means that, if a criterion of fixed percent difference criterion is used for satisfactory agreement, the number of discrepant readings is over-estimated at low parasite densities. With a criterion of fixed absolute difference, the same happens at high parasite densities. For an ideal slide, following the Poisson distribution, a criterion based on a constant difference in square root counts would apply for all densities. This can be back-transformed to a difference in absolute counts, which, as expected, gives a wider range of acceptable agreement at higher average densities. In an example dataset from Tanzania, observed differences in square root counts correspond to a 95% limits of agreement of -2,800 and +2,500 parasites/microl at average density of 2,000 parasites/microl, and -6,200 and +5,700 parasites/microl at 10,000 parasites/microl. However, there were more outliers beyond those ranges at higher densities, meaning that actual coverage of these ranges was not a constant 95%, but decreased with density. In a second study, a trial of microscopist training, the corresponding ranges of agreement are wider and asymmetrical: -8,600 to +5,200/microl, and -19,200 to +11,700/microl, respectively. By comparison, the optimal limits of agreement, corresponding to Poisson variation, are +/- 780 and +/- 1,800 parasites/microl, respectively. The focus of this approach on the volume of blood read leads to other conclusions. For example, no matter how large a volume of blood is read, some densities are too low to be reliably detected, which in turn means that disagreements on slide positivity may simply result from within-slide variation, rather than reading errors. CONCLUSIONS: The proposed method defines limits of acceptable agreement in a way which allows for the natural increase in variability with parasite density. This includes defining the levels of between-reader variability, which are consistent with random variation: disagreements within these limits should not trigger additional readings. This approach merits investigation in other settings, in order to determine both the extent of its applicability, and appropriate numerical values for limits of agreement
Letter re: S. 2875, Extension Air Port Act
No full textLetter from Lyndon B. Johnson to Amon G. Carter re: the passage of S. 2875 Airport Extension Bill by the Senate. Also included are a copies of the Bil
Telegram re: S. 2875, Extension Air Port Act
No full textTelegram from Lyndon B. Johnson to Amon G. Carter re: the Senate adopting S. 2875, Extension Air Port Act, this time sent to the Everglades Hotel in Florid
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