SECTORAL EFFECTS OF A WORLD OIL PRICE SHOCK: ECONOMYWIDE LINKAGES TO THE AGRICULTURAL SECTOR

The effects of a world oil price shock on U.S. agriculture are analyzed in an economywide environment. We use an input-output model to analyze the direct and indirect cost linkages between energy and other sectors of the economy. Then, to allow sectoral output adjustment and the effects on the U.S. current account, we use the U.S. Department of Agricultural/Economic Research Service Computable General Equilibrium (CGE) model to analyze the sectoral effects under three different macro adjustment scenarios. The effects on agriculture are not limited to the direct and indirect energy costs and government support programs for agricultural also matter.Agricultural Finance, Resource /Energy Economics and Policy,

Observations of Shear Stress Effects on Staphylococcus aureus Biofilm Formation

Staphylococcus aureus bacteria form biofilms and distinctive microcolony or tower structures that facilitate their ability to tolerate antibiotic treatment and to spread within the human body. The formation of microcolonies, which break off, get carried downstream, and serve to initiate biofilms in other parts of the body, is of particular interest here. It is known that flow conditions play a role in the development, dispersion, and propagation of biofilms in general. The influence of flow on microcolony formation and, ultimately, what factors lead to microcolony development are, however, not well understood. The hypothesis being examined is that microcolony structures form within a specific range of levels of shear stress. In this study, laminar shear flow over a range of 0.15 to 1.5 dynes/cm2 was examined. It was found that microcolony structures form in a narrow range of shear stresses around 0.6 dynes/cm2 Further, measurements of cell density as a function of space and time showed that shear dependence can be observed hours before microcolonies form. This is significant because, among other physiologic flows, this is the same shear stress found in large veins in the human vasculature, which, along with catheters of similar diameters and flow rates, may therefore play a critical role in biofilm development and subsequent spreading of infections throughout the body.IMPORTANCE It is well known that flow plays an important role in the formation, transportation, and dispersion of Staphylococcus aureus biofilms. What was heretofore not known was that the formation of tower structures in these biofilms is strongly shear stress dependent; there is, in fact, a narrow range of shear stresses in which the phenomenon occurs. This work quantifies the observed shear dependence in terms of cell growth, distribution, and fluid mechanics. It represents an important first step in opening up a line of questioning as to the interaction of fluid forces and their influence on the dynamics of tower formation, break-off, and transportation in biofilms by identifying the parameter space in which this phenomenon occurs. We have also introduced state-of-the-art flow measurement techniques to address this problem

Pnpla3 single nucleotide polymorphism prevalence and association with liver disease in a diverse cohort of persons living with hiv

In persons living with HIV (PLWH), there are multiple sources of liver injury. Gene polymorphisms of PNPLA3 (patatin-like phospholipase domain-containing protein 3) have been identified as an important cofactor for increased disease severity in both alcoholic and non-alcoholic steatohepatitis (NASH). We utilized a well-characterized cohort of ethnically and racially diverse patients with HIV to define the prevalence of PNPLA3 SNPs (single nucleotide polymorphism) (rs738409), and to determine the relationship to hepatic steatosis and liver fibrosis. Steatosis was determined using MRI-PDFF (magnetic resonance imaging-determined proton density fat fraction) and fibrosis was estimated using MR Elastography (MRE). From the Miami Area HIV Study (MASH) cohort, 100 HIV positive participants and 40 controls (HCV/HIV = 20; HCV and HIV negative = 20) were evaluated. Nearly 40% of all participants carried the variant G allele associated with increased liver disease severity and 5% were homozygotic GG. The variant SNP occurred most frequently in those self-identified as Hispanic compared to white or Black participants. Hepatic steatosis (\u3e5% fat) was present significantly more often in those without HIV vs. those with (p \u3c 0.001). Putative NAFLD/NASH was found to be present in 6% of tested subjects, who were HIV monoinfected. BMI was lower in those that carried the G allele for PNPLA3. This finding suggests that PNPLA3 may be an independent component to NAFLD (non-alcoholic fatty liver disease)/NASH development and longitudinal follow-up of the cohort is warranted

IL28B Alleles Exert an Additive Dose Effect When Applied to HCV-HIV Coinfected Persons Undergoing Peginterferon and Ribavirin Therapy

BACKGROUND: Genetic studies have demonstrated a strong association between single nucleotide polymorphisms (SNPs) at IL28B and response to treatment with peginterferon (PEG) and ribavirin (RBV) in HCV monoinfected persons. We sought to test these associations in a prospective PEG / weight based ribavirin (WBR) treatment trial (ACTG A5178) (National Institution of Health registration number NCT00078403) in persons with HCV-HIV coinfection, and to develop a prediction score. METHODS: We selected subjects enrolled in A5178 who completed at least the first 12 weeks of the trial and had DNA available, and genotyped three SNPs at IL28B (rs12979860, rs12980275, rs8099917). We used multivariate logistic regression analysis to evaluate the association between IL28B SNPs and HCV treatment outcomes and to develop the prediction score. RESULTS: 231 HCV/HIV coinfected subjects were included. We observed a strong association between IL28B genotype and response to therapy among those with genotypes 1 or 4 (odds ratio for complete early virologic responses (cEVR) and sustained virologic response (SVR) was 2.98 [1.7-5.3] and 3.4 [1.7-6.9], respectively, for each additional copy of the C allele of rs12979860). Differences in frequency of the responder allele explained some of the discrepancy in HCV treatment outcomes between blacks and whites. A simple pretreatment prediction score that incorporates the IL28B genotype and baseline HCV viral load has a 93% negative predictive value (NPV) for SVR. CONCLUSIONS: IL28B SNPs have an additive allele dose effect in predicting HCV treatment outcomes in HCV/HIV coinfected persons and can be incorporated into a simple pretreatment prediction score that could minimize the risk of exposure to PEG/RBV therapy for persons with unfavorable scores

Developing a collaborative framework for naturalistic visual search

While much research has investigated the mechanisms of visual search behaviour in laboratory-based computer tasks, there has been relatively little work on whether these results generalise to more naturalistic search tasks and thus how well existing theories explain real-world search behaviour. In addition, work relating to this question has often been carried out by researchers working in very different disciplines, including not just vision science but also fields such as consumer behaviour, sports science and medical science, making it more difficult to get an overview of the progress made and open questions remaining. We present findings from a systematic review of real-world visual search, showing that we can group the current literature into theoretical and applied approaches, and that there are certain well-studied topics (e.g., X-ray screening) but that there are relatively few links made across different search tasks and/or search contexts. We also present preliminary work detailing our development of a “naturalistic search task battery”, which aims to provide a suite of open source, reproducible and standardised real-world search tasks, thus enabling the generation of comparable data across multiple studies and aiding theory and modelling in this area

Importance of continued activation of thrombin reflected by fibrinopeptide A to the efficacy of thrombolysis

Factors responsible for initial success or failure of coronary thrombolysis and persistent recanalization or early reocclusion have not been thoroughly elucidated. Both adequate initial clot lysis and preclusion of rethrombosis are required. Failure may reflect clot lysis followed immediately or somewhat later by rethrombosis. To determine whether differences in the intensity and persistence of the activation of thrombin are determinants of success or failure of recanalization, plasma fibrinopeptide A, a fibrinogen product liberated by thrombin, was serially assayed in 19 patients treated with intravenous streptokinase. In patients exhibiting recanalization (n = 9), plasma fibrinopeptide A decreased after administration of streptokinase but before administration of heparin. In patients without initially apparent recanalization, fibrinopeptide A increased, suggesting ongoing thrombosis, and subsequently decreased promptly after heparin. In patients with initial recanalization followed by overt reocclusion the pattern was different. Despite recanalization, fibrinopeptide A continued to rise markedly. Elevations persisted despite administration of heparin. Thus, inhibition of activation of thrombin is associated with successful recanalization. Conversely, persistent activation of thrombin may be a predisposing factor to both apparent initial failure of recanalization and nvprt early reocclusion

Hepatitis C viral evolution in genotype 1 treatment-naïve and treatment-experienced patients receiving telaprevir-based therapy in clinical trials

Background: In patients with genotype 1 chronic hepatitis C infection, telaprevir (TVR) in combination with peginterferon and ribavirin (PR) significantly increased sustained virologic response (SVR) rates compared with PR alone. However, genotypic changes could be observed in TVR-treated patients who did not achieve an SVR. Methods: Population sequence analysis of the NS3•4A region was performed in patients who did not achieve SVR with TVR-based treatment. Results: Resistant variants were observed after treatment with a telaprevir-based regimen in 12% of treatment-naïve patients (ADVANCE; T12PR arm), 6% of prior relapsers, 24% of prior partial responders, and 51% of prior null responder patients (REALIZE, T12PR48 arms). NS3 protease variants V36M, R155K, and V36M+R155K emerged frequently in patients with genotype 1a and V36A, T54A, and A156S/T in patients with genotype 1b. Lower-level resistance to telaprevir was conferred by V36A/M, T54A/S, R155K/T, and A156S variants; and higher-level resistance to telaprevir was conferred by A156T and V36M+R155K variants. Virologic failure during telaprevir treatment was more common in patients with genotype 1a and in prior PR nonresponder patients and was associated with higher-level telaprevir-resistant variants. Relapse was usually associated with wild-type or lower-level resistant variants. After treatment, viral populations were wild-type with a median time of 10 months for genotype 1a and 3 weeks for genotype 1b patients. Conclusions: A consistent, subtype-dependent resistance profile was observed in patients who did not achieve an SVR with telaprevir-based treatment. The primary role of TVR is to inhibit wild-type virus and variants with lower-levels of resistance to telaprevir. The complementary role of PR is to clear any remaining telaprevir-resistant variants, especially higher-level telaprevir-resistant variants. Resistant variants are detectable in most patients who fail to achieve SVR, but their levels decline over time after treatment