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The severity of surficial liquefaction manifestation was significantly over-predicted for a large subset of case histories from relatively recent earthquakes that impacted the Canterbury region of New Zealand. Such over-predicts generally occurred for profiles having predominantly high fines-content (FC), high-plasticity soil strata. Herein, the liquefaction case histories from the Canterbury earthquakes are used to investigate the performances of three different manifestation severity index (MSI) models. The prevalence of high FC, high-plasticity strata in a profile is quantified through the soil behavior type index averaged over the upper 10 m of a profile ([I.sub.c10]). It is shown that for each MSI model (1) the threshold MSI value distinguishing cases with and without manifestation increases as [I.sub.c10] increases and (2) the ability of the MSI to segregate cases with and without manifestation decreases with increasing [I.sub.c10]. Additionally, probabilistic models are proposed for evaluating the severity of surficial liquefaction manifestation as a function of MSI and [I.sub.c10]. The approaches presented in this study allow better interpretations of predictions made by existing MSI models, although their efficacy decreases at sites with high [I.sub.c10]. An improved MSI model is ultimately needed that better accounts for the effects of high-FC, high-plasticity soils more directly. Key words: liquefaction, earthquake, manifestation severity index, Canterbury earthquakes, Introduction The objective of this study is to investigate the effect of high fines-content (FC), high-plasticity soils on the prediction of the occurrence and severity of surficial liquefaction manifestations at [...]

Mycobacteriophages are viruses that infect mycobacterial hosts such as Mycobacterium smegmatis and Mycobacterium tuberculosis. All mycobacteriophages characterized to date are dsDNA tailed phages, and have either siphoviral or myoviral morphotypes. However, their genetic diversity is considerable, and although sixty-two genomes have been sequenced and comparatively analyzed, these likely represent only a small portion of the diversity of the mycobacteriophage population at large. Here we report the isolation, sequencing and comparative genomic analysis of 18 new mycobacteriophages isolated from geographically distinct locations within the United States. Although no clear correlation between location and genome type can be discerned, these genomes expand our knowledge of mycobacteriophage diversity and enhance our understanding of the roles of mobile elements in viral evolution. Expansion of the number of mycobacteriophages grouped within Cluster A provides insights into the basis of immune specificity in these temperate phages, and we also describe a novel example of apparent immunity theft. The isolation and genomic analysis of bacteriophages by freshman college students provides an example of an authentic research experience for novice scientists.

Objectives: Despite recent foundation donations and bilateral commitments there are insufficient funds to implement all of the desired interventions for AIDS prevention and treatment. This paper explores one methodto analyze the allocation of limited budgets. Methods: Based on existing data from African countries, we compare the cost-effectiveness of both HIV prevention and treatment interventions using cost per life-year saved as the outcome measure. We examined five prevention interventions: (1) voluntary counseling and testing; (2) prevention of mother-to-child transmission; (3) STD mass treatment for general population; (4) STD management for sex workers; and (5) blood screening – and four drug price scenarios for antiretroviral treatment for HIV+ patients. In a hypothetical country of one million people and a generalized epidemic, we performed a static budgetary simulation with constrained resources to estimate total life-years gained and number of HIV cases prevented/treated with only prevention or treatment interventions. Results: Both the cost-effectiveness analysis and the budgetary analysis suggest that HIV prevention interventions are much more cost-effective than ARV treatment. Both blood screening and STD control among sex workers are the most cost-effective preventative interventions at the costs of $3.35 and $3.95 per life-year saved (LYS), respectively. ARV treatment is the least cost-effective, costing $1,317.20 per life-year saved at generic drug prices. In the budgetary simulation scenario with donated drugs, ARV treatment consumes the entire budget saving up to 2,974 life years annually. A portfolio of prevention interventions does not require the entire budget and results in 135,030 life years saved. Conclusions: Both the cost-effectiveness analysis and the budgetary analysis suggest that HIV prevention interventions should be prioritized if poor countries hope to maximize the scarce resources available for reducing the impact of the AIDS epidemic.

The 1994 International Conference on Population and Development (ICPD), held in Cairo, produced a Programme of Action accepted and signed by over 180 governments. The Programme of Action marked an important shift in the ideological framework of population programs. By stating such programs should ensure that “a full-range of reproductive health care services, including family planning, are accessible, affordable, acceptable and convenient to all users” (ICPD Programme of Action, 1994, 7.5.a), Cairo identified the crux of population programs to be the reproductive health of women, and expanded the notion of family planning accordingly. This bibliography was initiated as part of an effort to revise the original UNFPA estimates of the cost of implementing the Cairo agenda. It is focused on sub-Saharan Africa for two reasons. First, sub-Saharan Africa, by almost any measure, is most in need of improved provision of health services. Second, accuracy and completeness was a high priority, requiring that the scope be narrowed. Every effort was made to include all relevant literature published in developing countries or unpublished sources. It is primarily focused on recent literature, as the objective is to facilitate estimation of current and future implementation costs. When little or no cost estimates in sub-Saharan Africa are available, such as for breast cancer screening and treatment, we include cost estimates from outside the region. Within each topic references are organized in order (subjectively) of usefulness and quality. Each reference gives a description of points of the study relevant to the cost figures to the extent that the study presents itself. We briefly describe the methodology, including any information provided on which costs were included or not included. The costs presented are typically unit costs, where the units are most often per CYP, per capita, per illness and per affected individual. When additional calculations were necessary to produce unit costs, the additional figures used in the calculations are also presented. We provide the year-basis for the cost figures where possible and the exchange rate used where necessary. When the precise year-basis information was not available or was ambiguous in the source material we attempted provide the dates for the period of the intervention as available to offer some context for the cost data. We occasionally included dates in other references as well to offer addition context as necessary.

The energy dissipated in soil during cyclic loading can be used to predict the change in the pore-water pressure developed in the soil. To examine whether the energy required to cause liquefaction is dependent on or independent of the load shape applied, a series of 28 cyclic triaxial tests were performed using five different load shapes having a range of cyclic stress ratios. The five load shapes were applied to identically prepared specimens of clean sand and the dissipated energy--pore pressure generation characteristics examined. It was found that that the dissipated energy to cause initial liquefaction was normally distributed and independent of the load shape, although it is seemingly somewhat dependent on duration of loading. A corollary to this finding is that laboratory data from specimens tested using sinusoidal loadings can be used to calibrate the Green, Mitchell, and Polito (GMP) energy-based pore pressure generation model for use in predicting in situ pore pressures in soils subjected to nonsinusoidal loadings (e.g., earthquake loadings). Given the relative simplicity of the GMP model, these findings make the model an attractive alternative to implement in effective stress dynamic response codes. Key words: liquefaction, excess pore pressure generation, energy-based liquefaction methods. L'energie du sol dissipee durant les sollicitations cycliques peut etre utilisee pour predire les variations de pression interstitielle developpee dans le sol. Dans le but d'evaluer si l'energie necessaire pour causer la liquefaction est dependante ou independante de la forme de la sollicitation appliquee, une serie de 28 essais triaxiaux cycliques ont ete realises avec cinq formes de sollicitations differentes sur une variete de ratio de contrainte cyclique. Les cinq formes de sollicitations ont ete appliquees sur des echantillons identiques de sable propre et les caracteristiques de la dissipation de l'energie et des pressions interstitielles ont ete examinees. Il a ete observe que l'energie dissipee causant la liquefaction initiale est distribuee normalement et est independante de la forme de sollicitation, quoique l'energie semble legerement dependante de la duree de la sollicitation. Une information complementaire obtenue est que les donnees de laboratoire provenant d'echantillons testes avec des charges sinusoidales peuvent etre utilisees pour calibrer le modele de Green, Mitchell et Polito (GMP) de generation de pression interstitielle base sur l'energie, pour ensuite servir lors de la prediction des pressions interstitielles in-situ dans des sols soumis a des sollicitations non-sinusoidales (par exemple, des tremblements de terre). En raison de la simplicite relative du modele GMP, ces resultats font que le modele devient une alternative interessante pour l'integrer dans des codes de contrainte effective dynamique. [Traduit par la Redaction] Mots-cles: liquefaction, generation de pression interstitielle, methodes de liquefaction basees sur l'energie., Introduction Energy-based pore pressure models, which are used to predict the change in residual excess pore-water pressure in a soil subjected to cyclic loading, are an important emerging tool in [...]

This paper discusses the applicability of two simple models for predicting pore water pressure generation in nonplastic silty soil during cyclic loading. The first model was developed by Seed et al. in the 1970s and relates the pore pressure generated to the cycle ratio, which is the ratio of the number of applied cycles of loading to the number of cycles required to cause liquefaction. The second model is the Green-Mitchell-Polito model proposed by Green et al. in 2000, which relates pore pressure generation to the energy dissipated within the soil. Based upon the results of approximately 150 cyclic triaxial tests, the writers show that both models are applicable to silty soils. A nonlinear mixed effects model was used for regression analyses to develop correlations for the necessary calibration parameters. The results show that the trends in both [alpha] and pseudoenergy capacity calibration parameters for the Seed et al. and Green et al. pore pressure generation models, respectively, differ significantly for soils containing less than and greater than ~35% fines, consistent with the limiting fines content concept. CE Database subject headings: Dynamic analysis; Liquefaction; Pore pressure; Regression models; Silts; Sands; Cyclic loads.

As an alternative to a field-based liquefaction resistance approach, cyclic triaxial tests with bender elements were used to develop a new correlation between cyclic resistance ratio (CRR) and overburden stress-corrected shear-wave velocity ([V.sub.S1]) for two nonplastic silts obtained from Providence, Rhode Island. Samples of natural nonplastic silt were recovered by block sampling and from geotechnical borings/split-spoon sampling. The data show that the correlation is independent of the soils' stress history as well as the method used to prepare the silt for cyclic testing. The laboratory results indicate that using the existing field-based CRR-[V.sub.S1] correlations will significantly overestimate the cyclic resistance of the Providence silts. The strong dependency of the CRR-[V.sub.S1] curves on soil type also suggests the necessity of developing silt-specific liquefaction resistance curves from laboratory cyclic tests performed on reconstituted samples. DOI: 10.1061/(ASCE)1090-0241(2008)134:1(37) CE Database subject headings: Silts; Liquefaction; Cyclic tests; Shear waves; Velocity.