The problems of supplementary social insurance in Greece: Conclusions of a conference

No abstrac

The problems of supplementary social insurance in Greece: Conclusions of a conference

No abstrac

Serum and Urine α — Amylase Isoenzymes levels After Operative Cholangiogram

Serum and urine total α-amylase isoenzymes values were estimated in two groups of patients, who underwent either elective cholecystectomy and operative cholangiogram (group A — 59 patients) or cholecystectomy without operative cholangiogram (group B — 68 patients). Serum and urine total α-amylase and pancreatic isoamylase (p-type) values were statistically significantly increased within the first 24 postoperative hours as compared to the preoperative levels only in group A (p < 0.05). No clinical signs of pancreatitis were observed. Serum lipase alterations did not reach any statistically significant difference in either group. It is concluded that transient hyperamylasaemia after peroperative cholangiogram may be due to a reversible chemical pancreatitis caused by the infused opacifying agent into the common bile duct

The History of Reception of Charles S. Peirce in Greece

Despite the great interest on Peirce’s work in Europe especially from the 1960s onwards, Peirce’s name in Greek literature could be found only in introductory books of philosophy and in particular in those concerned with the theory of language. An exception is Evangelos Papanoutsos’ Pragmatism or Humanism: Elaboration and Criticism of the Theories of a Great Current of Contemporary Philosophy (Papanoutsos 1924), which studies pragmatism as it had been shaped mainly by F. C. S. Schiller. Refer..

The Use of Entropy as a Model Diagnostic in Rainfall-Runoff Modelling

Recent papers have called for the development of robust model diagnostics (in addition to traditional “measures of fit”) that provide insights on where model structural components and/or data may be insufficient. The potential of entropy measures to provide these in hydrology has not been adequately explored. Further, flow duration (FD) curves provide a useful visual diagnostic of catchment response, but attempts to quantify the fit of modelled versus observed FD curves to date have relied on using time series measures of fit. We note that Shannon entropy of flow is strongly related to the FD relationship, so suggest it provides a more appropriate quantitative measure of fit. This paper presents initial results from a study calibrating two rainfall-runoff models to 4 years of hourly data from the Mahurangi catchment, NZ. Kling-Gupta efficiency (KGE), Nash-Sutcliffe efficiency (NSE) and two entropy measures were considered. When assessed using a range of model diagnostics, KGE was overall the single best measure, outperforming NSE at all times. Entropy outperformed KGE over particular hydrograph sections, and we show performance may improve further with careful choice of discretisation. We demonstrate entropy’s strong relationship to FD and interrogate the performance of entropy measures in the presence of timing and bias errors. As entropy is insensitive to timing errors but very sensitive to most other errors (in sharp contrast to, e.g., the NSE measure) it potentially provides a useful diagnostic of the types of error present in combination with other OFs

Meta‐analysis of flow modeling performances—to build a matching system between catchment complexity and model types

Hydrological models play a significant role in modelling river flow for decision making support in water resource management. In the past decades, many researchers have made a great deal of efforts in calibrating and validating various models, with each study being focused on one or two models. As a result, there is a lack of comparative analysis on the performance of those models to guide hydrologists to choose appropriate models for the individual climate and physical conditions. This paper describes a two-level meta-analysis to develop a matching system between catchment complexity (based on catchment significant features (CSFs)) and model types. The intention is to use the available CSF information for choosing the most suitable model type for a given catchment. In this study, the CSFs include the elements of climate, soil type, land cover and catchment scale. Specific choices of model types in small and medium catchments are further explored with all CSF information obtained. In particular, it is interesting to find that semi-distributed models are the most suitable model type for catchments with the area over 3000 km2, regardless of other CSFs. The potential methodology for expanding the matching system between catchment complexity and model complexity is discussed. Copyright © 2014 John Wiley & Sons, Ltd

Intercomparison of regional-scale hydrological models and climate change impacts projected for 12 large river basins worldwide - A synthesis

An intercomparison of climate change impacts projected by nine regional-scale hydrological models for 12 large river basins on all continents was performed, and sources of uncertainty were quantified in the framework of the ISIMIP project. The models ECOMAG, HBV, HYMOD, HYPE, mHM, SWAT, SWIM, VIC and WaterGAP3 were applied in the following basins: Rhine and Tagus in Europe, Niger and Blue Nile in Africa, Ganges, Lena, Upper Yellow and Upper Yangtze in Asia, Upper Mississippi, MacKenzie and Upper Amazon in America, and Darling in Australia. The model calibration and validation was done using WATCH climate data for the period 1971–2000. The results, evaluated with 14 criteria, are mostly satisfactory, except for the low flow. Climate change impacts were analyzed using projections from five global climate models under four representative concentration pathways. Trends in the period 2070–2099 in relation to the reference period 1975–2004 were evaluated for three variables: the long-term mean annual flow and high and low flow percentiles Q 10 and Q 90, as well as for flows in three months high- and low-flow periods denoted as HF and LF. For three river basins: the Lena, MacKenzie and Tagus strong trends in all five variables were found (except for Q 10 in the MacKenzie); trends with moderate certainty for three to five variables were confirmed for the Rhine, Ganges and Upper Mississippi; and increases in HF and LF were found for the Upper Amazon, Upper Yangtze and Upper Yellow. The analysis of projected streamflow seasonality demonstrated increasing streamflow volumes during the high-flow period in four basins influenced by monsoonal precipitation (Ganges, Upper Amazon, Upper Yangtze and Upper Yellow), an amplification of the snowmelt flood peaks in the Lena and MacKenzie, and a substantial decrease of discharge in the Tagus (all months). The overall average fractions of uncertainty for the annual mean flow projections in the multi-model ensemble applied for all basins were 57% for GCMs, 27% for RCPs, and 16% for hydrological models

COMPUTATION OF OPTIMUM WATER COURSE FLOW VELOCITY FOR THE SUSTAINABLE OPERATION OF A FISH REFUGE LATERALLY TO THE FLOW

Στην εργασία πραγματοποιήθηκαν εργαστηριακές μετρήσεις και ανάπτυξη μαθηματικών μοντέλων κυκλοφορίας και μεταφοράς συντηρητικού αιωρήματος για τον υπολογισμό της βέλτιστης ταχύτητας ροής υδατορεύματος για τη βιώσιμη λειτουργία ιχθυοδεξαμενής παράπλευρα της ροής, όπως εμφανίζεται στο ποτάμιο περιβάλλον με τις φυσικές ή τεχνητές δεξαμενές ιχθυοπληθυσμών παράπλευρα στην ροή του κύριου ρεύματος. Τα αποτελέσματα δείχνουν ότι όσον αφορά την παγίδευση αιωρουμένων στην ιχθυοδεξαμενή η καλύτερη περίπτωση (μικρότερη παγίδευση) είναι αυτή στην οποία η ταχύτητα του κυρίου ρεύματος είναι περίπου 0.30 m/s, η οποία βρίσκεται σε συμφωνία με την βέλτιστη ταχύτητα συνθηκών διαβίωσης των ψαριών.In this study the development of mathematical models of hydrodynamic circulation and matter transport and laboratory measurements for the computation of optimum watercourse flow velocity for the sustainable operation of a natural or artificial fish refuge laterally to the main riverine low were held. Concerning the trapping of the suspended particles in the fish reservoir, the results show, that the best case (with the minor trapping) corresponds to flow velocity of the main stream approximately 0.30 m/s, which is in very good agreement with the optimal living conditions of the fishes

The Significance of Spatial Variability of Rainfall on Runoff

A key issue in rainfall-runoff modelling is to assess the importance of the spatial representation of rainfall on streamflow generation. Distributed models have the potential to represent the effects of spatially variable inputs such as rainfall making them an appropriate tool to investigate the role of spatial rainfall on runoff. This paper explores the importance of spatial rainfall representation for rainfall-runoff modelling as a function of catchment scale and type. The study investigated the effect of catchment scale and type using 9 gauged catchments ranging in size from 30 to 1040 km2. Regional relationships between known catchment characteristics and model parameters have been developed to overcome the task of estimating model parameter values at ungauged subcatchments. The results indicate the importance of considering the effect of spatial rainfall in most of the catchments with the significance of spatial effects increasing at small spatial scales. Finally, the importance of spatial variability is enhanced when impermeable areas are investigated

Towards a smartphone-aided electronic ELISA for real-time electrochemical monitoring

This paper details the design and fabrication of a portable, smartphone-integrated electronic platform, tailored to read-out electronic ELISA (eELISA) data from printed circuit board (PCB)-based sensors. The instrument features eight independent, re-configurable current input channels, each consisting of a low-noise transimpedance amplifier (TIA) and filtering stage coupled to low-noise switch ICs for automatic current range detection. A bipolar, 16-bit resolution voltage-input analog-to-digital converter (ADC) has been employed for digitisation of converted current values received from the analogue front-end. In addition, a bipolar, 12-bit resolution digital-to-analog converter (DAC) combined with standard three-electrode potentiostats provides wide range biasing voltages to the amperometric sensors. The resulting digital data is transmitted via serial interface to an Android-based smartphone, where an ergonomic user interface guides the operator through the detection process. The customised Android application (App) provides real-time monitoring of the electrochemical cell and stores returned biochemical data on the device once measurement is complete