442 research outputs found

    Image Analysis for Facility Siting: a Comparison of Lowand High-altitude Image Interpretability for Land Use/land Cover Mapping

    Get PDF
    For two test sites in Pennsylvania the interpretability of commercially acquired low-altitude and existing high-altitude aerial photography are documented in terms of time, costs, and accuracy for Anderson Level II land use/land cover mapping. Information extracted from the imagery is to be used in the evaluation process for siting energy facilities. Land use/land cover maps were drawn at 1:24,000 scale using commercially flown color infrared photography obtained from the United States Geological Surveys' EROS Data Center. Detailed accuracy assessment of the maps generated by manual image analysis was accomplished employing a stratified unaligned adequate class representation. Both 'area-weighted' and 'by-class' accuracies were documented and field-verified. A discrepancy map was also drawn to illustrate differences in classifications between the two map scales. Results show that the 1:24,000 scale map set was more accurate (99% to 94% area-weighted) than the 1:62,500 scale set, especially when sampled by class (96% to 66%). The 1:24,000 scale maps were also more time-consuming and costly to produce, due mainly to higher image acquisition costs

    Determinação do potássio em fertilizantes por fotometria de chama de emissão

    Get PDF
    In this paper was studied the flame photometric method for potassium determination in fertilizers using only aqueous extract of fertilizer and aqueous extract content ammonium oxalate, comparatively with the volumetric sodium tetraphenyboron (STPB) method. The flame photometric method using only aqueous extract presented results always down of that STPB method being its relative error on an avarage - 0.76% with potassium fertilizer materials and approximately - 3% with mixtures. The flame photometric method using aqueous extract content ammonium oxalate presented results enough near that STPB method, being its relative error on an avarage - 0.35% with potassium fertilizer materials and approximately 0.7% with mixtures but alternated among positive and negative error. The precision of both photometric method is very high but it must have much care with dilutions, that are larges.O presente trabalho teve por objetivo o estudo do método fotométrico de chama para a determinação do potássio em fertilizantes quando aplicado em extrato simplesmente aquoso e em extrato aquoso contendo oxalato de amônio, comparativamente com o método volumétrico do tetrafenilborato de sódio (TFBS). Os dados obtidos mostraram que o método fotométrico de chama baseado no emprego de extratos simplesmente aquosos de fertilizantes apresentou resultados sempre inferiores ao obtidos pelo método do T.F.B.S. e seu relativo foi, em média, de - 0,76% nos fertilizantes simples e em torno de - 3% nas misturas de fertilizantes. O método fotométrico de chama baseado no emprego de extratos aquosos contendo oxalato de amônio apresentou resultados bastante próximos aos obtidos com o método do T.F.B.S. e seu erro relativo foi, em média, de - 0,35% nos fertilizantes simples e em torno de 0,7% nas misturas de fertilizantes, mas com a alternância entre positivo e negativo. A preciasão foi elevada, mas esmerado cuidado é exigido nas diluições

    Different proportion of root cutting and shoot pruning influence the growth of citronella plants

    Get PDF
    Environment concern, sustainable products demand, and natural components conscious are currently global movement factors. Related to the global movement factors, citronella grass (Cymbopogon nardus L.) is being widely used in folk medicine, and has insect repellent activity, fungal and bactericidal action. Its essential oil has high content of citronellal, citronellol, geraniol. The essential oil is mostly extracted from leaves which turns this plant with high commercial demand. However, to obtain the best therapeutic quality and productivity of medicinal plants, which culminates in greater quantity and quality of the active compounds, the proper management of the crop is fundamental, as several factors can interfere during its growth and development. Thus, we analyzed the growth of citronella plants submitted to different levels of shoot and root cuts. Five different proportions of root pruning (0, 25, 50, 75, 100%), after 145 days of seedling planting and four cuttings in the shoots: blunt; a cut at 145 DAP (days after planting) along with the root cut; a cut at 228 DAP; and cuts at 145 and 228 DAP (two cuts). Four harvesting for dry matter accumulation and photoassimilate partition data were performed. The treatment with 100% root cut, but without leaf cut, increased the total dry mass accumulation of the plant in relation to the other treatments, for the last analysis period, demonstrating a recovery. Thus, the application of two leaf cuts or no leaf cutting within the 100% root cut treatment for leaf dry mass accumulation is more effective when compared to the blunt root treatment

    Preterm birth is not associated with asymptomatic/mild SARS-CoV-2 infection per se: Pre-pregnancy state is what matters

    Get PDF
    Evidence for the real impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on preterm birth is unclear, as available series report composite pregnancy outcomes and/or do not stratify patients according to disease severity. The purpose of the research was to determine the real impact of asymptomatic/mild SARS-CoV-2 infection on preterm birth not due to maternal respiratory failure. This case-control study involved women admitted to Sant Anna Hospital, Turin, for delivery between 20 September 2020 and 9 January 2021. The cumulative incidence of Coronavirus disease-19 was compared between preterm birth (case group, n = 102) and full-term delivery (control group, n = 127). Only women with spontaneous or medically-indicated preterm birth because of placental vascular malperfusion (pregnancy-related hypertension and its complications) were included. Current or past SARS-CoV-2 infection was determined by nasopharyngeal swab testing and detection of IgM/IgG antibodies in blood samples. A significant difference in the cumulative incidence of Coronavirus disease-19 between the case (21/102, 20.5%) and the control group (32/127, 25.1%) (P= 0.50) was not observed, although the case group was burdened by a higher prevalence of three known risk factors (body mass index > 24.9, asthma, chronic hypertension) for severe Coronavirus disease-19. Logistic regression analysis showed that asymptomatic/mild SARS-CoV-2 infection was not an independent predictor of spontaneous and medically-indicated preterm birth due to pregnancy-related hypertension and its complications (0.77; 95% confidence interval, 0.41-1.43). Pregnant patients without comorbidities need to be reassured that asymptomatic/mild SARS-CoV-2 infection does not increase the risk of preterm delivery. Preterm birth and severe Coronavirus disease-19 share common risk factors (i.e., body mass index > 24.9, asthma, chronic hypertension), which may explain the high rate of indicated preterm birth due to maternal conditions reported in the literature

    Increased Placental Anti‐Oxidant Response in Asymptomatic and Symptomatic COVID‐19 Third‐Trimester Pregnancies

    Get PDF
    Despite Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) -induced Oxidative Stress (OxS) being well documented in different organs, the molecular pathways underlying placental OxS in late-pregnancy women with SARS-CoV-2 infection are poorly understood. Herein, we performed an observational study to determine whether placentae of women testing positive for SARS-CoV-2 during the third trimester of pregnancy showed redox-related alterations involving Catalase (CAT) and Superoxide Dismutase (SOD) antioxidant enzymes as well as placenta morphological anomalies relative to a cohort of healthy pregnant women. Next, we evaluated if placental redox-related alterations and mitochondria pathological changes were correlated with the presence of maternal symptoms. We observed ultrastructural alterations of placental mitochondria accompanied by increased levels of oxidative stress markers Thiobarbituric Acid Reactive Substances (TBARS) and Hypoxia Inducible Factor-1 α (HIF-1α) in SARS-CoV-2 women during the third trimester of pregnancy. Importantly, we found an increase in placental CAT and SOD antioxidant enzymes accompanied by physiological neonatal outcomes. Our findings strongly suggest a placenta-mediated OxS inhibition in response to SARS-CoV-2 infection, thus contrasting the cytotoxic profile caused by Coronavirus Disease 2019 (COVID-19)
    corecore