About
56
Publications
4,346
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
872
Citations
Introduction
Skills and Expertise
Publications
Publications (56)
The pollination of several crops, as well as wild plants, depends on honeybees. To get the nutrients required for growth and survival, honeybee colonies are dependent on pollen supply. Bee pollen (BP) is partially packed in honeycomb cells and processed into beebread (BB) by microbial metabolism. The composition of pollen is highly variable and is...
The term Conjugated Linoleic Acid (CLA) refers generically to a class of positional and geometric conjugated dienoic isomers of linoleic acid. Among the isomers of linoleic acid cis9, trans11-CLA (c9, t11-CLA) and trans10, cis12-CLA (t10, c12-CLA) are found to be bio-logically active isomers, and they occur naturally in milk, dairy products and mea...
Galdieria spp. (Rhodophyta) are polyextremophile microalgae known for their important antioxidant properties in different biological systems. Nowadays, the beneficial and bio-stimulant effect of microalgal extracts is widely tested on crops. Here, for the first time, potential positive effects of aqueous extracts from Galdieria were tested on a sec...
The aim of the work was to study the biological interference of the spontaneous colonization of pathogenic and saprophytic endophytes on the nitrogen assimilation of mycorrhized wheat plants cultivated in soils deficient in N and P. The nitrogen assimilation efficiency of mycorrhized plants was determined by measuring the activities of nitrate redu...
Minimizing nitrification of fertilizer ammonium (NH 4 +) can reduce nitrate (NO 3 −) contamination of groundwater and increase nitrogen (N) use efficiency (NUE). Olive mill wastewater (OMW), hydroalcoholic extracts of Mentha piperita L. (Mp) and Artemisia annua L. (Aa), and synthetic nitrification inhibitor (NI) dicyandiamide (DCD) were investigate...
Pancratium maritimum (Amaryllidaceae) is a bulbous geophyte growing on coastal sands. In this study, we investigated changes in concentrations of metabolites in the root and leaf tissue of P. maritimum in response to mild salt stress. Changes in concentrations of osmolytes, glutathione, sodium, mineral nutrients, enzymes, and other compounds in the...
Despite being an autotrophic organism, Galdieria phlegrea (Galdieriaceae) has the ability to use glycerol thereby switching to heterotrophy in the dark and mixotrophy in the presence of light. To examine cellular changes during the switch to mixotrophic metabolism and finally to photoautotrophic metabolism, heterotrophic cells of G. phlegrea were e...
The application of mycorrhizal fungi in agricultural soils as bio-fertilizers is going to be established as an agronomic practice for enhancing crop nutrients acquisition and production. In this work, the effects of tomato root colonization by arbuscular mycorrhizal fungus Glomus mosseae, on nitrogen metabolism, fructification and environmental sus...
The aim of this work was to study the effect of arbuscular mycorrhizal fungus Glomus mosseae on growth and nitrogen (N) metabolism of durum wheat (Tritcum durum) under various P soil contents. The analyses were extended to macro and micronutrient tissue concentrations, nitrate reductase and glutamine synthetase activities, as well as protein, amino...
This paper investigates SLA violations of a production SaaS platform by means of joint use of field failure data analysis (FFDA) and fault injection. The objective of this study is to diagnose the causes of SLA violations, pinpoint critical failure modes under realistic error assumptions and identify potential means to increase the user perceived a...
This paper provides an analysis of failures and their impact for Blue Waters, the Cray hybrid (CPU/GPU) supercomputer at the University of Illinois at Urbana-Champaign. The analysis is based on both manual failure reports and automatically generated event logs collected over 261 days. Results include i) a characterization of the root causes of sing...
This paper proposes a heuristic to improve the analysis of supercomputers error logs. The heuristic is able to estimate the error on the measurement induced by the clustering process of error events and consequently drive the analysis. The goal is to reduce errors induced by the clustering and be able to estimate how much they affect the measuremen...
Computer systems are intertwined in many modern human activities and, more importantly, they play key roles in critical domains. As such, it is critically important to assess the dependability of computing systems. Data collected under real workload conditions can provide troves of valuable information about the stresses the systems encounter and t...
Wireless Sensor Networks (WSNs) are widely recognized as a promising solution to build next-generation monitoring systems. Their industrial uptake is however still compromised by the low level of trust on their performance and dependability. Whereas analytical models represent a valid mean to assess nonfunctional properties via simulation, their wi...
This article consists of a collection of slides from the author's PowerPoint conference presentation. A procedure and a statistical model to measure the risk of error when processing a workload X is proposed. It is concluded that architecting hazard-aware load balancer for Cloud SaaS can be promising.
Safety-critical medical monitoring systems have always suffered from false alarms and misdetection issues, sensitivity to external perturbations and internal faults, which could be catastrophic for patients. We address the main challenges faced towards the resiliency of medical monitoring devices by introducing a novel reconfigurable hardware archi...
Current studies in plants suggest that the content of the coenzyme NAD is variable and potentially important in determining cell fate. In cases that implicate NAD consumption, re-synthesis must occur to maintain dinucleotide pools. Despite information on the pathways involved in NAD synthesis in plants, the existence of a mitochondrial nicotinamide...
Abiotic stresses, such as high salinity or drought, can cause proline accumulation in plants. Such an accumulation involves proline transport into mitochondria where proline catabolism occurs. By using durum wheat seedlings as a plant model system, we investigated how proline enters isolated coupled mitochondria. The occurrence of two separate tran...
In N-sufficient cells of Chlorella sorokiniana Shihira and Krauss strain 211/8K (CCAP of Cambridge University), assimilation of ammonium was strictly dependent on light and CO2, and was severely inhibited by 100 μM atrazine or 10 μM 3-(3,4-dichlorophenyl)-1, l-dimethylurea (DCMU). In N-limited cells, assimilation of NH4+ took place at similar rates...
Cyanidium caldarium is an acidophilic thermophilic red alga. At pH 1.9 with cells grown in batch culture with excess ammonium, removal of CO2 or darkness caused immediate inhibition of ammonium assimilation. By contrast, with cells grown in chemostat culture with nitrogen limitation, assimilation of ammonium was not inhibited by darkness, but it wa...
Summary • The aim of the paper was to determine nitrogen compounds contributing to leaf cell osmoregulation of spinach (Spinacia oleracea) submitted to increasing salt stress. • Sodium, free amino acids and glycine betaine contents were determined in the last fully expanded leaf of plants stressed by daily irrigation with saline water (0.17 M NaCl)...
We analyzed the effect of NaCl stress on photorespiration of spinach leaves by calculating the rate of carboxylation/oxygenation
of ribulose-1,5-bisphosphate carboxylase/oxygenase, and by measuring the content of amino acids produced through photorespiration.
After 20 d of NaCl stress the carboxylation rate was reduced while the oxygenation rate wa...
The rise in the concentration of CO2 in the atmosphere since the start of industrialization, and the global warming associated with this greenhouse gas, has stimulated research into the response of plants to elevated levels of CO2. Much of this work has been carried out in controlled environments which provide limited information about long-term ef...
Low water potential, generated by PEG addition to the liquid medium of hydroponically grown pea seedlings, induces a fall in moisture content in the roots, followed by the arrest of elongation. This water stress reduces the mitotic index of root meristems during the treatment and induces the appearance of a peak of mitosis at 12 hours from the begi...
Proline/glutamate antiport in rat kidney mitochondria has been studied in terms of two different features: energy dependence and glutamate-carrier contribution to accomplish proline movement across the mitochondrial membrane.
Energy dependence of the proline/glutamate antiporter in rat kidney mitochondria has been investigated by means of both spec...
In order to ascertain whether oxidative phosphorylation in plant mitochondria is sensitive to light, coupled durum wheat (Triticum durum Desf.) mitochondria were irradiated with a low power continuous wave Helium-Neon laser (fluence: 2 Joules/cm2), with measurements made of certain processes related to ATP production. As a result of irradiation, an...
Growth, intrácellular free amino acid pools and photosynthetic and respiratory activities in nutrient sufficient cells and in N- K- and P-limited cells of Cyanidium caldarium (Tilden) Geitler, and responses to nutrient resupply were investigated. Addition of ammonium to N-limited cells and of phosphate to P-limited cells resulted in a stimulation o...
Amino acid pools in Cyanidium caldarium (Tilden) Geitler, growing under conditions of sufficiency of nutrients (sufficient cells), or under conditions of nitrogen, potassium or phosphorus limitation (N-, K- or P-limited cells), and responses upon nutrient resupply were investigated. Glutamate was the dominant amino acid in sufficient cells [11.2 μm...
The assimilation of ammonium by N-sufficient cells of unicellular algae is strictly dependent on light and CO2. However, cells previously kept under conditions of nitrogen starvation (Thacker and Syrett 1972; Syrett et al. 1986), or cells grown in chemostat culture under conditions of nitrogen limitation (Di Martino Rigano et al. 1986), can assimil...
Cells of Cyanidium caldarium grown in batch under conditions of excess ammonium or nitrate contained respectively 11.2 and 11.7 μmol glutamate/ml packed cell volume (pcv). Glutamate was the dominant amino acid, and represented 40–43.3% of the total amino acid concentration; other amino acids detected, occurring at a lower level with respect to glut...
Cyanidium caldarium (Tilden) Geitler, a non-vacuolate unicellular alga, resuspended in medium flushed with air enriched with 5% CO2, assimilated NH4+ at high rates both in the light and in the dark. The assimilation of NO3−, by contrast, was inhibited by 63% in the dark. In cell suspensions flushed with CO2-free air, NH4+ assimilation decreased wit...
Chlorella vulgaris Beijerinck, strain 211/12, uses nitrate, nitrite and ammonium at pH 8.2 but not at pH 6.4 when kept under conditions of CO2-deprivation, as observed in cell suspensions aerated with CO2-free air during a 20–30. h period Most of the nitrate absorbed at pH 8.2, however, was not assimilated but was released into the external medium...
Chemostat cultures of the unicellular alga Cyanidium caldarium have shown that under conditions of phosphate limitation nitrate reductase is completely derepressed even in cells growing in a large excess of ammonium, but that it occurs mainly in a catalytically inactive form. It is hypothesized that phosphate limitation contributes to maintaining i...
In the unicellular non-vacuolate red alga Cyanidium caldarium nitrate uptake occurs through two specific permease systems which, on the basis of kinetic constants can be defined as low affinity system and high affinity system. The high affinity system is saturated at very low nitrate concentrations (M), whereas the low affinity system is saturated...
Cells of Chlorella vulgaris (Cambridge culture collection, strain 211/12) grown in chemostat under conditions of nitrate limitation, exhibit very high levels of nitrate reductase activity. Similar levels of activity were found in cells grown in chemostat with a limited nitrogen source constituted by 75% ammonium plus 25% nitrate. By contrast, cells...
