370 research outputs found
Automated classification of Persistent Scatterers Interferometry time series
We present a new method for the automatic classification of Persistent Scatters Interferometry (PSI) time series based on a conditional sequence of statistical tests. Time series are classified into distinctive predefined target trends, such as uncorrelated, linear, quadratic, bilinear and discontinuous, that describe different styles of ground deformation. Our automatic analysis overcomes limits related to the visual classification of PSI time series, which cannot be carried out systematically for large datasets. The method has been tested with reference to landslides using PSI datasets covering the northern Apennines of Italy. The clear distinction between the relative frequency of uncorrelated, linear and non-linear time series with respect to mean velocity distribution suggests that different target trends are related to different physical processes that are likely to control slope movements. The spatial distribution of classified time series is also consistent with respect the known distribution of flat areas, slopes and landslides in the tests area. Classified time series enhances the radar interpretation of slope movements at the site scale, pointing out significant advantages in comparison with the conventional analysis based solely on the mean velocity. The test application also warns against potentially misleading classification outputs in case of datasets affected by systematic errors. Although the method was developed and tested to investigate landslides, it should be also useful for the analysis of other ground deformation processes such as subsidence, swelling/shrinkage of soils, or uplifts due to deep injections in reservoirs
The use of fluorescence to investigate the factors leading to complex formation between naphthalenes and ß-cyclodextrins
Fraiji et al. determined a binding constant (K) of 581 = 6 M-1 for the 1:1 complex between 2-acetylnaphthalene (2-AN) and β-cyclodextrin (β-CD) in H20 using fluorescence quenching experiments (Appl. Spectrosc. 1994, 48, 79). Molecular modeling experiments indicate the possibility of complex stabilization resulting from hydrogen bonds between the C=O group of 2-AN and the -OH groups on the rim of β-CD. To check this possibility, we measured the K of the 2-AN:trimethyl-β-CD (TM-β- CD) complex, where all rim -OH groups are converted to –OCH3. In this case, K decreases to 134 M-1. To show that this is due to reduced hydrogen bonding capability rather than steric influence, the K of 2-AN: β-CD was measured at high pH. K decreases to 276 M-1 at pH 13.5, and an inflection point is observed at pH 12.2 (which is the pKa of rim -OH groups). Therefore, our experiments confirm the significance of 2-AN carbonyl hydrogen bonding to β-CD -OH groups. Fluorescence studies were also performed with 1,5-DNSA, 2,6-MANS, and 2,6- TNS. K was 151M-1 for 1,5-DNSA: β-CD and 105M-1 for 1,5-DNSA:TM-β-CD. The smaller K for the TM-β-CD complex is probably due to steric effects associated with the rim -OCH, groups. Thermodynamic properties of the 2,6-MANS:TM-β-CD complex were investigated. ΔH and ΔS were calculated as -35 kJ/mol and -47 J/mol K, respectively. Catena and Bright calculated ΔH as -6.7 kJ/mol and AS as 50 J/mol K for the 2,6-MANS: β-CD complex (Anal. Chem. 1989, 61, 915). The methyl groups of the TM-β-CD make the cavity environment more hydrophobic than the natural β -CD, creating much stronger guest:host interations. The methyl groups also restrict the motion of 2,6-MANS, which overcomes the favored entropic effects of solvent replacement and solvent shell disturbance. The 2,6-TNS:TM-β-CD, K was calculated as 2358 M-1, compared to Catena and Bright\u27s 1980 M-1 for the β-CD complex. The more hydrophobic cavity of TM-β-CD compensates for the loss of hydrogen bonding between the guest SO3- group and CD rim -OH groups. CE was employed for the separation of LSD (d-lysergic acid diethylamide), LAMPA (D-lysergic acid methylpropylamide) and iso-LSD using several types of cyclodextrins as buffer additives. A sample consisting of LSD, LAMPA, and iso-LSD was partially resolved (R\u3e1) with 60 mM α-CD in a 50 mM acetate buffer, pH 4.03, at 15°C. Migration times were under 9 min. Another solution consisting of both 60 mM α-CD and 0.2 mM sulfated-β-CD in 50 mM acetate buffer, pH 4.03, at 25°C provided baseline separation (R\u3e 1.5) of the sample mixture in a similar 9 min. time window. The reproducibility of migration times for both methods was 4-5% between days and 1% on the same day. Partial separation of LSD and LAMPA (R~1) was (observed in a 9 min. time window using 15 mM sulfated-α-CO in a 50 mM borate buffer, pH 8.51 at 25°C. Between day and same day reproducibilities were 2-3% and 1%, respectively
Simulation-based flood fragility and vulnerability analysis for expanding cities
Accurately quantifying flood-induced impacts on buildings and other infrastructure systems is essential for risk-sensitive planning and decision-making in expanding urban regions. Flood-induced impacts are directly related to the physical components of assets damaged due to contact with water. Such components include building contents (e.g., appliances, furniture) and other non-structural components whose damage/unavailability can severely impact the buildingsďľ’ functionality. Conventional fragility analysis approaches for flooding do not account for the physical damage to the individual components, mostly relying on empirical methods based on historical data. However, recent studies proposed simulation-based, assembly-based fragility models that account for the damage to the building components. Such fragility models require developing detailed inventories of vulnerable components of households and identifying building archetypes to be considered in a building portfolio for the region of interest. Content inventories and building portfolios have so far been obtained for specific socio-economic contexts such as the United States of America. However, building types and their content can significantly differ between countries, making the available fragility models and computational frameworks unsuitable for flood vulnerability analysis in rapidly expanding cities characterised by extensive informal settlements, such as low- and middle-income countries. This paper details how to adapt the available methodologies for flood vulnerability assessment to the context of formal and informal settlements of expanding cities in the global south. It also details the development of content inventories for households in these cities using field surveys. The proposed survey is deployed in various areas vulnerable to floods in Kathmandu, Nepal. Based on the survey results, each component within the household is associated with a corresponding flood capacity (resistance) distribution (in terms of water height and flood duration). These distributions are then employed in a simulation-based probabilistic framework to obtain fragility relationship and consequence models. The relevant differences between the results obtained in this study and those from previous studies are then investigated for a case-study building type. In addition, the influence of socio-economic factors (e.g., household income) and past flood experience (possibly resulting in various flood-risk mitigation strategies at a household level) on the resulting flood impacts is also included in the model
SINOPSIS DE LAS ESPECIES DE MYXOZOA GRASSÉ, 1970 (CNIDARIA: MYXOSPOREA) EN LAS AMÉRICAS
Una sinopsis de los registros de las especies válidas de mixozoários (Myxozoa: Myxosporea) descritas en las AmĂ©ricas se proporciona con base en un levantamiento bibliográfico desde 1893, cuando la primera especie de mixosporĂdeo fue descrita, hasta diciembre de 2016. Esta es una sinopsis de 495 especies, Distribuidas en 36 gĂ©neros, 15 familias y asociadas a 286 especies de hospedadores. En tĂ©rminos de nĂşmero de asociaciones hospedador-parasito, los peces fueron el grupo más representativo (97% del nĂşmero total de asociaciones hospedador-parasito, mientras que los registros en las aves representaron el 0,2%, los crustáceos 0,2%, helmintos 0,2, 0,8% reptiles y 1,6% fueron en los anfibios. El nĂşmero de descripciones de mixozoarios fue mayor en la RegiĂłn Neártica en relaciĂłn a la RegiĂłn Neotropical. La sinopsis incluye una lista parásito-hospedador con datos sobre el hábitat del hospedador, el sitio de infecciĂłn, la localidad, el tamaño y el formato del quiste, las medidas de las esporas y los especĂmenes en las colecciones y una lista de los parásitos
Imaging technologies in the differential diagnosis and follow-up of brown tumor in primary hyperparathyroidism: case report and review of the literature
Brown tumors are osteolytic lesions associated with hyperparathyroidism (HPT). They may involve various skeletal segments, but rarely the cranio-facial bones. We report a case of a young boy with a swelling of the jaw secondary to a brown tumor presenting as the first manifestation of primary HPT (PHPT). He was found to have brown tumor located in the skull, as well. Different imaging technologies were employed for the diagnosis and follow-up after parathyroidectomy. We enclose a review of the literature on the employment of such imaging technologies in the differential diagnosis of osteolytic lesions. A multidisciplinary approach comprising clinical, laboratory and imaging findings is essential for the differential diagnosis of brown tumor in PHPT
Activity and safety of RAD001 (everolimus) in patients affected by biliary tract cancer progressing after prior chemotherapy: a phase II ITMO study.
BACKGROUND:
Biliary tract cancer (BTC) is a highly lethal disease for which the best available therapy remains undetermined. The mammalian target of rapamycin (mTOR) pathway is up-regulated in several cancers, including BTC, and preclinical evidence indicates that mTOR inhibition may be effective in the treatment of BTC. We sought to evaluate the activity and tolerability of the mTOR inhibitor RAD001-everolimus-in patients with BTC progressing after prior chemotherapy.
PATIENTS AND METHODS:
This was an open-label, single-arm, phase II study (EUDRACT 2008-007152-94) conducted in eight sites in Italy. Patients with locally advanced, metastatic or recurrent BTC progressing despite previous chemotherapy received a daily oral dose of everolimus 10 mg administered continuously in 28-day cycles. The two primary end points were disease control rate (DCR) and objective response rate (ORR). Secondary end points were progression-free survival (PFS), overall survival (OS) and time-to-progression (TTP).
RESULTS:
Thirty-nine patients were enrolled. The DCR was 44.7%, and the ORR was 5.1%. One patient showed a partial response at 2 months and one patient showed a complete response sustained up to 8 months. The median (95% confidence interval) PFS was 3.2 (1.8-4.0) months, and the median OS was 7.7 (5.5-13.2) months. The median TTP was 2.0 (1.7-3.7) months. Most common toxicities were asthenia (43.6%), thrombocytopenia (35.9%), pyrexia (30.8%) and erythema, mainly of mild-to-moderate severity. Two patients required dose reduction due to adverse events.
CONCLUSION:
Everolimus demonstrated a favourable toxicity profile and encouraging anti-tumour activity. Further trials are needed to establish the role of everolimus in the treatment of BTC. EUDRACT 2008-007152-94
Kupffer Cells Hasten Resolution of Liver Immunopathology in Mouse Models of Viral Hepatitis
Kupffer cells (KCs) are widely considered important contributors to liver injury during viral hepatitis due to their pro-inflammatory activity. Herein we utilized hepatitis B virus (HBV)-replication competent transgenic mice and wild-type mice infected with a hepatotropic adenovirus to demonstrate that KCs do not directly induce hepatocellular injury nor do they affect the pathogenic potential of virus-specific CD8 T cells. Instead, KCs limit the severity of liver immunopathology. Mechanistically, our results are most compatible with the hypothesis that KCs contain liver immunopathology by removing apoptotic hepatocytes in a manner largely dependent on scavenger receptors. Apoptotic hepatocytes not readily removed by KCs become secondarily necrotic and release high-mobility group box 1 (HMGB-1) protein, promoting organ infiltration by inflammatory cells, particularly neutrophils. Overall, these results indicate that KCs resolve rather than worsen liver immunopathology
CRECIMIENTO ANTE LA RESPUESTA VISUAL Y REGĂŤMENES PROLONGADOS DE ALIMENTACIĂ“N EN EL BIORREGULADOR LARVAL DE MOSQUITOS GAMBUSIA PUNCTATA POEY, 1854
El objetivo del estudio fue evaluar la respuesta visual ante regĂmenes prolongados de alimentaciĂłn en el biorregulador larval de mosquitos Gambusia punctata Poey, 1854. El estudio se realizĂł bajo condiciones controladas. Se expusieron a 5 juveniles (< 1,7 cm) de G. punctata en cuatro tratamientos sin rĂ©plica. Uno de ellos consistiĂł en el control (alimentaciĂłn diaria: T ) mientras que los restantes consistieron en 1 alimentaciĂłn prolongada con intervalo regular por siete dĂas (T : 7 dĂas, T : 14 dĂas y T : 21 dĂas). Al 2 3 4 trascurrir sus intervalos regulares de tiempo se les suministraron al T , harina de pescado no comercial 1 mientras que, el resto de los tratamientos consumiĂł, larvas del mosquito Aedes aegypti (Linnaeus, 1762). Se observĂł la respuesta visual de los individuos juveniles por exposiciĂłn al alimento en cada tratamiento experimental donde hubo diferencias estadĂsticamente significativas. Sin embargo, no se encontrĂł diferencias estadĂsticamente significativas en el tiempo de respuesta visual, despuĂ©s que se produjo el cambio de alimentaciĂłn. Se concluyĂł que, el crecimiento se afecta cuando la disponibilidad de alimento se prolonga y ocurre un cambio en la preferencia alimentaria independientemente que, la respuesta visual ante la detecciĂłn y consumo del alimento sea inmediata en juveniles del biorregulador G. punctata
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