Canopy Resistance and Actual Evapotranspiration over an Olive Orchard

Τhis study evaluates the hourly actual evapotranspiration (AΕT), predicted either by the two modified Penman-Monteith models (PM) which take into account the canopy resistance (r_c) from the Katerji-Perrier (KP) or Todorovic (TD) models, or the simplified PM model with zero r_c, as proposed by Priestley and Taylor (PT). The evaluation is based on comparisons with experimental measurements of AΕT applying the ‘Bowen ratio’ method. Hourly experimental data, of air temperature, humidity, wind speed and radiation balance measurements, taken at a 0.5 ha olive orchard in the rural area of Sparta (37° 04? N, 22°05? E), during the period from June 2010 up to July 2014, are used. The r_c estimated by KP model is parameterized by a semi-empirical approach which requires a simple calibration procedure, while r_c from TD model is parameterized using a theoretical approach. For estimating AET from minimum data (air temperature, humidity and radiation balance components) the PT model is also employed, since r_c is not required and the aerodynamic term of PM is taken into account in the empirical parameter of the model. The results show that PT and KP models are the most appropriate [Refined Index of Agreement (RIA) equal to 0.89 or 0.88, respectively] followed by the TD model (RIA?=?0.78). PT or KP models underestimate AET by 9.3% or 9.8%, respectively, while TD model overestimates AET by 15.0%, increased up to 25.8%, during warm period.     

Selection of thermal,spectroscopic, spectrometric,and chromatographic methods for characterizing historical celluloid

Celluloid in museum collections is very unstable; therefore, heritage professionals carry out research studies dedicated to understanding its decay and prolonging its lifetime. This paper addresses the need to compare and select suitable analytical methods for that purpose. Thermogravimetric analysis coupled with Fourier transform infrared spectroscopy, evolved gas analysis–mass spectrometry, double shot – gas chromatography/mass spectrometry, and gel permeation chromatography (GPC) were employed to characterize the emission of gasses (decay products) and measure the molecular weight and camphor (plasticizer) content from unaged, artificially, and naturally aged celluloid samples. A pioneer GPC set-up for the quantification of camphor was introduced for the first time in this study. Results demonstrated that GPC was the most suitable method for assessing material changes due to degradation. Both set-ups, for measuring molecular weight and quantifying camphor, appear promising for assessing the effect of conservation treatments and investigating the heterogeneous degradation of celluloid objects in future studies.     

A genetic circuit amplifier: design and simulation

A genetic circuit amplifier is designed using an electronic inverting amplifier as a starting point. Two simulation methods are used to analyze circuit performance in terms of the impulse and sinusoidal responses of electrical engineering. The first method is an exact stochastic simulation based on a kinetic model of the circuit. The second method incorporates statistical thermodynamic analysis. The simulations are used to analyze amplifier performance in response to classical systems analysis stimuli: impulses and sine waves. Degradation reactions, analogous to leakage off circuit capacitors, are found to have considerable impact on circuit response. For the nonlinear gain element used in our exemplary circuit, the selection of bias level based on controlling protein degradation rate plays an important role in determining circuit behavior. A parameter without electronic analog, the circuit plasmid copy number, is crucial to circuit operation. These simulations suggest that the copy number must be less than 50 for desired circuit operation.     

Assessment of geothermal potential of central and southern Tuscany

Central and southern Tuscany contain all the presently exploited geothermal fields of Italy, and accordingly were chosen to test the geothermal resource assessment methodology described by Muffler and Cataldi (this issue). Using new compilations at 1:200,000 of all available drill-hole, geological, gravity, and thermal-gradient data, the region was divided into 31 zones, each of reasonably homogenous geology and thermal regime. The upper 3 km of each area was then divided by horizontal surfaces into three volumes consisting of (1) the impermeable cover (Neoautochthon, Ligurids, and the upper terrigenous part of the Tuscan Series), (2) the Jurassic and Triassic rocks that form the main reservoir complex (the lower carbonate part of the Tuscan Series) and (3) the underlying Triassic and Paleozoic quartzite and phyllite of low porosity, thus allowing calculation of geothermal energy in both rock and pore water. The aggregate of these values is the “accessible geothermal resource base” of central and southern Tuscany.     

Vis-NIR Hyperspectral and Terahertz Imaging Investigations on a Fresco Painting on “Tavella” by Alessandro Gherardini

In this paper, we report on Vis-IR hyperspectral and terahertz imaging investigations carried out on a fresco painting on tavella depicting St. John Baptist, by Alessandro Gherardini (1655–1726). Measurements took place at the Restoration Laboratories of the former “Polo Museale della Toscana,” in Florence, in the framework of the Italy-Japan collaborative project THz-ARTE. We show how the hyperspectral data made it possible to determine the state-of-conservation of Gherardini’s painting, while reflection imaging measurements performed at 97 GHz provided a qualitative evaluation of the position of defects inside the tavella.     

Structures and functions of calcium channel beta subunits

Calcium channel beta subunits have profound effects on how alpha1 subunits perform. In this article we summarize our present knowledge of the primary structures of beta subunits as deduced from cDNAs and illustrate their different properties. Upon co-expression with alpha1 subunits, the effects of beta subunits vary somewhat between L-type and non-L-type channels mostly because the two types of channels have different responses to voltage which are affected by beta subunits, such as long-lasting prepulse facilitation of alpha1C (absent in alpha1E) and inhibition by G protein betagamma dimer of alpha1E, absent in alpha1C. One beta subunit, a brain beta2a splice variant that is palmitoylated, has several effects not seen with any of the others, and these are due to palmitoylation. We also illustrate the finding that functional expression of alpha1 in oocytes requires a beta subunit even if the final channel shows no evidence for its presence. We propose two structural models for Ca2+ channels to account for "alpha1 alone" channels seen in cells with limited beta subunit expression. In one model, beta dissociates from the mature alpha1 after proper folding and membrane insertion. Regulated channels seen upon co-expression of high levels of beta would then have subunit composition alpha1beta. In the other model, the "chaperoning" beta remains associated with the mature channel and "alpha1 alone" channels would in fact be alpha1beta channels. Upon co-expression of high levels of beta the regulated channels would have composition [alpha1beta]beta.     

Cell proliferation induced by 8-oxoguanosine and 8-methylguanosine, two adducts produced by free radical attack on ribonucleosides and RNA

The vowel "eh" was used to study auditory-nerve responses at high sound levels (60-110 dB). By changing the playback sampling rate of the stimulus, the second formant (F2) frequency was set at best frequency (BF) for fibers with BFs between 1 and 3 kHz. For vowel stimuli, auditory-nerve fibers tend to phase-lock to the formant component nearest the fiber's BF. The responses of fibers with BFs near F2 are captured by the F2 component, meaning that fibers respond as if the stimulus consisted only of the F2 component. These narrowband responses are seen up to levels of 80-100 dB, above which a response to F1 emerges. The F1 response grows, at the expense of the F2 response, and is dominant at the highest levels. The level at which the F1 response appears is BF dependent and is higher at lower BFs. This effect appears to be suppression of the F2 response by F1. At levels near 100 dB, a component 1/component 2 transition is observed. All components of the vowel undergo the transition simultaneously, as judged by the 180 degrees phase inversion that occurs at the C2 transition. Above the C2 threshold, a broadband response to many components of the vowel is observed. These results demonstrate that the neural representation of speech in normal ears is degraded at high sound levels, such as those used in hearing aids.     

E-commerce system quality assessment using a model based on ISO 9126 and Belief Networks

As business transitions into the new economy, e-system successful use has become a strategic goal. Especially in business to consumer (e-commerce) applications, users highly evaluate the quality of their interactive shopping experience. However, quality is difficult to define and measure and most importantly, it is difficult to measure its impact on the end-user. Among the many research questions that arise, some of the most important concern the exact nature of the quality attributes that define an e-commerce system, and how one could model these attributes in order to increase its acceptance. Bearing in mind that e-commerce systems are actually user/data-intensive web-based software systems, this work performed a survey which resulted in a theoretical model that helps to measure such systems’ dynamics through their decomposition into primary quality characteristics. The proposed model is based on Bayesian Networks and ISO 9126. Besides the emphasis on specific software quality attributes, it also provides a quality assessment process aiding developers to design and produce e-commerce systems of high quality. Using a Bayesian Network the model can be used to combine different types of evidences and provide reasoning from effect to cause and vice versa.