Memory Mangement in the PoSSo Solver

AbstractA uniform general purpose garbage collector may not always provide optimal performance. Sometimes an algorithm exhibits a predictable pattern of memory usage that could be exploited, delaying as much as possible the intervention of the collector. This requires a collector whose strategy can be customized to the need of an algorithm. We present a dynamic memory management framework which allows such customization, while preserving the convenience of automatic collection in the normal case. The Customizable Memory Management (CMM) organizes memory in multiple heaps, each one encapsulating a particular storage discipline. The default heap for collectable objects uses the technique of mostly copying garbage collection, providing good performance and memory compaction. Customization of the collector is achieved through object orientation by specialising the collector methods for each heap class. We describe how the CMM has been exploited in the implementation of the Buchberger algorithm, by using a special heap for temporary objects created during polynomial reduction. The solution drastically reduces the overall cost of memory allocation in the algorithm

Key For The Identification Of Mediterranean Brachyuran Megalopae

Based on larval literature, an identification key has been constructed for the megalopae of 55 species of Mediterranean Brachyura. This key is based mainly on external morphological characteristics visible, by using a microscope, limiting the necessity for dissection of specimens. Characteristics used include presence/absence of ornamentation on the carapace, number of abdominal somites, number and position of setae and/or spines on antennula, antenna, pereiopods and structure of uropods, etc. Partial dissection is only required to count the setae on the scaphognathite margin. Using the above characters, it is also possible to gather almost all the families into groups. However, the megalopae of Portunidae as well as those of the three species of Brachynotus genus are similar to each other and their identification at a specific level requires the use of features somehow variable and difficult to count. In the Majidae, the megalopae of 14 species are already known. The complexity of morphological characters typical of this family makes it difficult to define characters common to all spider crab megalopae. Nevertheless, the key may be an aid for carcinology studies, especially those including sorting and identification of megalopae from plankton samples

Changes in antioxidant defence system in durum wheat under hyperosmotic stress: A concise overview

Durum wheat is one of the most commonly cultivated species in the world and represents a key commodity for many areas worldwide, as its grain is used for production of many foods, such as pasta, bread, couscous, and bourghul. Durum wheat grain has a relevant role in the human diet, providing carbohydrates, proteins, lipids, fibres, vitamins, and minerals, as well as highly valued bioactive compounds contributing to a healthy diet. Durum wheat is largely cultivated in the Mediterranean basin, where it is mainly grown under rain-fed conditions, thus currently undergoing drought stress, as well as soil salinity, which can hamper yield potential and influence the qualitative characteristics of grain. When plants suffer drought and/or salinity stress, a condition known as hyperosmotic stress is established at cellular level. This leads to the accumulation of ROS thus generating in turn an oxidative stress condition, which can ultimately result in the impairment of cellular integrity and functionality. To counteract oxidative damage due to excessive ROS production under stress, plants have evolved a complex array of both enzymatic and non-enzymatic antioxidant mechanisms, working jointly and synergically for maintenance of ROS homeostasis. Enhancement of antioxidant defence system has been demonstrated as an adaptive mechanism associated to an increased tolerance to hyperosmotic stress. In the light of these considerations, this review provides a concise overview on recent advancements regarding the role of the ascorbate-glutathione cycle and the main antioxidant enzymes (superoxide dismutase, catalase, and peroxidases) in durum wheat response to drought and salt stresses that are expected to become more and more frequent due to the ongoing climate changes

Influence of drought and salt stress on durum wheat grain quality and composition: A review

Durum wheat is a staple crop for the Mediterranean diet because of its adaptability to environmental pressure and for its large use in cereal-based food products, such as pasta and bread, as a source of calories and proteins. Durum wheat whole grains are also highly valued for their peculiar amount of dietary fiber and minerals, as well as bioactive compounds of particular interest for their putative health-beneficial properties, including polyphenols, carotenoids, tocopherols, tocotrienols, and phytosterols. In Mediterranean environments, durum wheat is mostly grown under rainfed conditions, where the crop often experiences environmental stresses, especially water deficit and soil salinity that may induce a hyperosmotic stress. In particular, changes in C and N accumulation due to these abiotic conditions, during grain filling, can influence starch and storage protein amount and composition in durum wheat caryopsis, thus influencing yield and quality traits. Recent advancements regarding the influence of water deficit and salinity stress on durum wheat are critically discussed. In particular, a focus on stress-induced changes in (a) grain protein content and composition in relation to technological and health quality; (b) starch and dietary fiber accumulation and composition; (c) phytochemical composition; (d) health-related grain micronutrient accumulation, such as Fe and Zn

Antioxidant Activity of Free and Bound Compounds in Quinoa (Chenopodium quinoa Willd.) Seeds in Comparison with Durum Wheat and Emmer

Antioxidant activity (AA) of quinoa (Chenopodium quinoa Willd.) seeds, as well as of durum wheat (Triticum turgidum L. ssp. durum Desf.) and of emmer (T. turgidum L. ssp. dicoccum Sch¨ubler) grains, was evaluated by studying hydrophilic (H), lipophilic (L), free-soluble (FSP) and insoluble-bound (IBP) phenolic extracts using the new lipoxygenase/4-nitroso-N,N-dimethylaniline (LOX/RNO) method, able to simultaneously detect different antioxidant mechanisms, as well as using the Oxygen Radical Absorbance Capacity (ORAC) and the Trolox Equivalent Antioxidant Capacity (TEAC) assays, which measure the scavenging activity against peroxyl and ABTS [2,2-azino-bis-(3- ethylbenzothiazoline-6-sulfonate)] radicals, respectively. The species under study were compared with respect to the sum of AA values of H, L and FSP extracts (AAH+L+FSP), containing freely solvent-soluble antioxidants, and AA values of IBP extracts (AAIBP), representing the phenolic fraction ester-linked to insoluble cell wall polymers. The LOX/RNO and ORAC methods measured in quinoa flour a remarkable AAH+L+FSP higher than durum wheat, although lower than emmer; according to the same assays, the IBP component of quinoa resulted less active than the durum wheat and emmer ones. The TEAC protocol also revealed a high AAH+L+FSP for quinoa. Interestingly, the ratio AAH+L+FSP/AAH+L+FSP+IBP, as evaluated by the LOX/RNO and ORAC assays, resulted in quinoa higher than that of both durum wheat and emmer, and much higher than durum wheat, according to the TEAC protocol. This may suggest that antioxidants from quinoa seeds may be more readily accessible with respect to that of both the examined wheat species

Effect of Arbuscular Mycorrhizal Fungal Seed Coating on Grain Protein and Mineral Composition of Old and Modern Bread Wheat Genotypes

The effect of arbuscular mycorrhizal fungi (AMF) on yield and quality was investigated on a set of seven bread wheat genotypes with varying years of release, including five old genotypes and two modern varieties. A two-year field trial was conducted in central Italy under rainfed con- ditions. The effect of AM fungal seed coating was proved by assessing the AM fungal root colonization and studied on agronomic and quality traits, and in particular on gluten-forming proteins and grain mineral composition. AMF seed coating led to a general yield improvement in old geno- types (+24%). Concerning the effects on grain quality, while modern genotypes showed an increase in protein content (+16%), in the old ones an improvement of gluten quality was observed, with an increased proportion of HMW-GS from +17% to +92%. The gluten index results were mostly influenced by HMW-GS allelic configuration and amount, showing a significant correlation with gliadin- to-glutenin ratio and HMW-GS to LMW-GS. Concerning mineral uptake, AM fungal treatment de- termined a general increase in P content, which was more marked in the modern group (+44%). Furthermore, AMF significantly increased mean Fe concentration in Verna (+53%) and Bologna (+45%). Finally, phytate content did not increase with AMF, without affecting mineral bioavailability

Analysis of gluten proteins composition during grain filling in two durum wheat cultivars submitted to two water regimes

Durum wheat ( Triticum turgidum L. subsp . durum) is one of the major crops in the Mediterranean basin, where water stress often occurs during grain filling which represents a critical stage for the synthesis and accumulation of storage proteins (gliadins and glutenins). The aim of the study is to evaluate, by two-dimensional gel electrophoresis (2DE SDS-PAGE), the storage proteins composition of two durum wheat cultivars (Ciccio and Svevo) cultivated in a growth chamber under two different water regimes (control and water deficit). At milk stage and physiological maturity, gluten proteins have been extracted and separated by 2DE SDS-PAGE. The analysis of the gels was performed by the software ImageMaster 2D Platinum (Amersham). The results showed differences in protein expression within the different gel regions between water regimes and cultivars; under water deficit the rate of protein accumulation was faster for all the protein regions, either at milk and physiological stage. Protein accumulation within high molecular weight (H) region resulted faster in Ciccio than in Svevo mainly in the control treatment. In the low molecular weight region between 48 and 35 kDa (L 48-35), the cultivar Ciccio showed a higher protein expression than Svevo. Furthermore under water deficit a marked increase in H region volume and a decrease in the L 48-35 region was observed only for Svevo; instead in Ciccio no change was observed showing this cultivar a greater stability on changing water regime. Further studies by the use of mass spectrometry are necessary to identify specific peptides relative to drought stress during grain filling as well as to investigate the relationships with technological quality

Position, swimming direction and group size of fin whales (Balaenoptera physalus) in the presence of a fast-ferry in the Bay of Biscay

We analyze group size, swimming direction and the orientation of fin whales relative to a fast ferry in the Bay of Biscay. Fin whale groups (≥3 individuals) were on average closer to the vessel than single individuals and pairs (F1,114 = 4.94, p = 0.028) and were more often observed within a high-risk angle ahead of the ferry (binomial probability: p = 7.60 × 10−11). Also, small groups tend to swim in the opposite direction (heading of 180°) of the ferry at the starboard side (binomial test: p = 6.86 × 10−5) and at the portside (binomial test: p = 0.0156). These findings provide valuable information to improve shipping management procedures in areas at high risk for collisions