2,349 research outputs found

    The United States in the Anthropocene

    Get PDF
    This seventh issue of USAbroad aims to look at American history and politics through an environmental lens and reframe the United States’ upward trajectory as a world power in the context of the Anthropocene. In particular, each article offers a unique way to view the intersection of American history, politics, society, and natural resources, showing how the rise of US power—from the late 19th-century imperial project to 20th-century techno-politics—is inextricably linked to the natural elements

    America's Energy Transition, the Evolution of the National Interest, and the Middle Eastern Connection at the Dawn of the Twentieth Century

    Get PDF
    The dissertation investigates the origins of Washington’s interest in petroleum and the elements that originally shaped the country’s foreign oil policy in the early twentieth century. The chapters center on the analysis of the American political debate and give special consideration to the international race to secure oil concessions in the Middle East that began before WWI and that culminated in the early 1920s. The study follows the establishment of a new, more assertive stance towards the securing of sources of supply in U.S. politics, and looks at the parallel evolution of concept of national interest. In examining the process of actual policy-formation, the research looks into the discussion between the various branches and departments of the administration, as well as between the federal government and the other private actors involved in petroleum exploration and production. The aim is to reconstruct the arguments that were used to support Washington’s drive toward the acquisition of petroleum supply, in order to understand how the access to oil resources – both at home and abroad – was presented, justified, and pursued before the American public

    Early impairment of endothelial structure and function in young normal-weight women with polycystic ovary syndrome

    Get PDF
    The aim of this study was to evaluate the presence of early vascular damage in young normal-weight women with polycystic ovary syndrome (PCOS).Thirty young normal-weight women with PCOS, who had no additional metabolic or cardiovascular diseases, and 30 healthy women (controls) matched for age and body mass index were studied. A complete hormonal assay was performed in each subject. Serum insulin and glucose levels were measured at baseline and after the oral glucose tolerance test. Plasma endothelin-1 levels and serum lipid profile were also assessed. The endothelial function was studied by flow-mediated dilation on the brachial artery, and arterial structure was evaluated by intima-media thickness measurement using Doppler ultrasound of both common carotid arteries.A significant (P < 0.05) difference in flow-mediated dilation (14.3 +/- 1.9% vs. 18.1 +/- 2.0% for PCOS patients and controls, respectively) and in intima-media thickness (0.53 +/- 0.09 mm vs. 0.39 +/- 0.08 mm for PCOS patients and controls, respectively) was found between PCOS and control subjects. Serum endothelin-1 levels were also significantly (P < 0.05) higher in PCOS patients compared with controls (1.1 +/- 0.4 pmol/liter vs. 0.5 +/- 0.2 pmol/liter for PCOS patients and controls, respectively).In conclusion, our data show that young, normal-weight, nondyslipidemic, nonhypertensive women with PCOS have an early impairment of endothelial structure and function

    Herbicidal potential of phenolic and cyanogenic glycoside compounds isolated from Mediterranean plants

    Get PDF
    This study was conducted to test five phenolic and cyanogenic glycoside compounds for growth regulating activity on the germination and seedling growth of Portulaca oleracea L., Amaranthus retroflexus L., and Lactuca sativa L. at different concentrations. Overall, the tested compounds revealed growth-regulating activity in species-specific and concentration dependent manner. The most powerful effects were much pronounced on seedling growth rather than on germination. In fact, the compounds 1 (amygdalin) and 2 (salicylic acid) were the most phytotoxic on root growth of  P. oleracea, and they caused, respectively, an inhibition of 55% and 85% at 10-6 M and 10-4 M. On the other hand, the lettuce seedling growth was more sensitive than weeds growth to the compounds 4 (3,4,5-trihydroxybenzoic acid) and 5 (7-hydroxycoumarin), which exhibited a moderate inhibition at the highest concentration. This selectivity and specificity of these active allelopathic compounds could be very useful for the development of new application of natural substances to control the aggressive weeds. Thus, our findings suggest that the integration of these compounds may maintain irrigation system and reduce the massive use of agrochemicals in agro-ecosystems

    Risk factors and outcome among a large patient cohort with community-acquired acute hepatitis C in Italy

    Get PDF
    BACKGROUND: The epidemiology of acute hepatitis C has changed during the past decade in Western countries. Acute HCV infection has a high rate of chronicity, but it is unclear when patients with acute infection should be treated. METHODS: To evaluate current sources of hepatitis C virus (HCV) transmission in Italy and to assess the rate of and factors associated with chronic infection, we enrolled 214 consecutive patients with newly acquired hepatitis C during 1999-2004. The patients were from 12 health care centers throughout the country, and they were followed up for a mean (+/- SD) period of 14+/-15.8 months. Biochemical liver tests were performed, and HCV RNA levels were monitored. RESULTS: A total of 146 patients (68%) had symptomatic disease. The most common risk factors for acquiring hepatitis C that were reported were intravenous drug use and medical procedures. The proportion of subjects with spontaneous resolution of infection was 36%. The average timespan from disease onset to HCV RNA clearance was 71 days (range, 27-173 days). In fact, 58 (80%) of 73 patients with self-limiting hepatitis experienced HCV RNA clearance within 3 months of disease onset. Multiple logistic regression analyses showed that none of the variables considered (including asymptomatic disease) were associated with increased risk of developing chronic hepatitis C. CONCLUSIONS: These findings underscore the importance of medical procedures as risk factors in the current spread of HCV infection in Italy. Because nearly all patients with acute, self-limiting hepatitis C - both symptomatic and asymptomatic - have spontaneous viral clearance within 3 months of disease onset, it seems reasonable to start treatment after this time period ends to avoid costly and useless treatment

    The prognostic role of different renal function phenotypes in patients with acute heart failure

    Get PDF
    Objective: Worsening renal function (WRF) is common in patients treated for acute heart failure (AHF) and might be associated with a significant increase in blood nitrogen urea (BUN). Although many patients develop WRF during hospitalisation, its prognostic role is still unclear. Thus, we aimed to evaluate the prognostic relevance of WRF according to BUN changes during hospitalization. Methods: We studied patients with AHF screened for Diur-HF Trial (NCT01441245). WRF was defined as an in-hospital rise in serum creatinine ≥0.3 mg/dl or estimated glomerular filtration rate (GFR) reduction ≥20%. BUN increase was defined as a rise in BUN ≥20% during admission. Effective decongestion was defined as complete resolution of two, or more, signs of HF, or absence of clinical signs of congestion at discharge. Results: Of 247 patients enrolled, 59 (23%) patients experienced WRF, 107 (43%) had a BUN increase ≥20%, and 111 (45%) were effectively decongested during hospitalization. During 180 days of follow-up, 136 patients died or were re-hospitalised for AHF. An increase in BUN was an independent predictor of adverse outcome, regardless of WRF (HR = 2.19 [1.35–3.54], p = 0.002 and 1.71 [1.14–2.59], p = 0.010; with and without WRF, respectively) or congestion at discharge. WRF was not an independent predictor of outcome if BUN did not increase or when congestion was effectively relieved. Conclusions: an increase in BUN≥20% during hospitalization for AHF predicts a poor outcome independently from renal function deterioration and decongestion. WRF predicts adverse outcome only if BUN increases substantially or clinical congestion persists

    Silymarin from Silybum marianum by Naviglio’s extractor: a new and very efficient approach

    Get PDF
    The aim of this work is to compare new and traditional extraction methods to obtain silymarin from Silybum marianum, a biennial herbaceous plant of the Asteraceae family, present throughout the Mediterranean basin and used to treat several diseases. Silymarin primarily contains flavonolignans and flavonoids and is used in some pharmaceutical preparations to improve of liver function and as a protective against some hepatotoxins. In six extracts obtained by new and traditional extraction methods, the total contents of silymarin and its main flavonolignans, total phenols and condensed tannins were evaluated in addition to their respective antioxidant capacities. By the Naviglio extractor, that is a rapid solid-liquid dynamic extraction method, it is possible to obtain a fraction quantitatively more abundant than other methods, and with a lower content of tannins and phenolic compounds but with a higher content of flavonolignans, rare and expensive, and therefore easier to separate and purify

    Custom-Made Implants in Ankle Bone Loss: A Retrospective Assessment of Reconstruction/Arthrodesis in Sequelae of Septic Non-Union of the Tibial Pilon

    Get PDF
    Background and Objectives: Treating segmental tibial and ankle bone loss after radical surgery for chronic osteomyelitis is one of the most challenging problems encountered by orthopaedic surgeons. Open tibia and ankle fractures occur with an incidence of 3.4 per 100,000 and 1.6 per 100,000, respectively, and there is a high propensity of developing fracture-related infection with associated chronic osteomyelitis in patients. Segmental tibial and ankle bone loss have recently received new and improved treatments. Materials and Methods: Above all, 3D printing allows for the customization of implants based on the anatomy of each patient, using a personalized process through the layer-by-layer deposition of materials. Results: This article presents different cases from the authors' experience. Specifically, four patients suffered tibia and ankle fractures and after radical surgery for chronic osteomyelitis combined with high-performance antibiotic therapy underwent ankle reconstruction/arthrodesis with custom-made tibial spacers. Conclusions: Thanks to 3D-printed patient-specific devices, it is possible to perform surgical procedures that, for anatomical reasons, would have been impossible otherwise. Moreover, an improvement in overall functionality and an important reduction in pain were shown in the last follow-up in all patients
    • …
    corecore