Birthweigh by gestational age in preterm babies according to a gaussian mixture model

Objectives. A statistically sound criterion for identifying implausible birthweights for gestational age. Methods. Data are from Italian 1990-94 vital statistics, and concern 42063 single first and second liveborn preterm babies. Two-component Gaussian mixture models are used to describe the birthweight distributions stratified by gestational age. Implausibly large babies are identified through model-based probabilistic clustering. Results. Gestational age appears underestimated of about six weeks in 12.3% of the cases. Large babies are equally present in males and females, but are more frequent among the second borns than in the first borns, even when parity specific models are fitted. Conclusions. The approach allows for a quantification of the gestational age underestimate error and data correction through model-based clustering. Correct birthweigh distributions and growth curves are also provided

Effects of Cadmium on the Metabolic Activity of Avena sativa Plants Grown in Soil or Hydroponic Culture

Oat (Avena sativa L.) plants cultured in soil and hydroponic culture were treated with cadmium [0.154 mg g -1 (dry soil) and 100 µM CdSO4, respectively] for 21 d and growth rate and various biochemical processes were studied. Applied cadmium reduced plant growth and chlorophyll content. Changes in activity of enzymes involved in C, N and S metabolism and in guaiacol peroxidase activity were observed. In particular, O-acetylserine sulphydrylase (OASS; EC 4.2.99.8) activity was increased by Cd exposure in both growth conditions, probably as a resistance mechanism to cadmium based on the production of phytochelatins. Results show that both field and hydroponic conditions represent suitable systems for investigating Cd effects on plant growth and metabolism. Additional keywords: carbon metabolism, nitrogen metabolism, sulphur metabolism, guaiacol peroxidase activity

Evaluation of a Legume-Derived Protein Hydrolysate to Mitigate Iron Deficiency in Plants.

Biostimulants play an important role in the development of management practices able to reach adequate productivity to meet the food demand of a growing world population, while following a sustainable agriculture model. This work aims to evaluate the effect of a protein hydrolysate derived from legume seeds by enzymatic hydrolysis on plant growth and also to verify its ability to mitigate Fe deficiency, a widespread problem significantly limiting plant growth and crop productivity. Experiments were performed with tomato (Solanum lycopersicum L.-cv. AKRAI F1) and cucumber (Cucumis sativus L.-cv. EKRON F1). The plants were grown hydroponically under adequate or limited Fe supply. Changes in shoot and root fresh weight, leaf relative chlorophyll content and the accumulation of macro- and microelements in shoots and roots were measured. Plant ability to cope with Fe deficiency was measured by evaluating the activity of root Fe3+-chelate reductase. Our results indicate that the foliar treatments with the protein hydrolysate did not significantly affect growth parameters when plants were grown in full nutrient solution. However, the biostimulant was able to improve the growth performance of Fe-deficient plants. Therefore, the protein hydrolysate can be a powerful tool to stimulate crop growth under Fe-deficient environments, leading to reduced fertilizer inputs with related environmental and economic benefits

Potential Use of Copper-Contaminated Soils for Hemp (Cannabis sativa L.) Cultivation.

To mitigate climate change, reducing greenhouse gas emissions can be achieved by decreasing the use of fossil fuels and increasing that of alternative sources, such as energy crops. However, one of the most important problems in the use of biomass as a fuel is that of changing soil use and consumption, leading to competition with food crops. We addressed the topic by evaluating the possibility to exploit contaminated areas for energy crops cultivation. Indeed, soil contamination makes land inappropriate for cultivation, with damaging consequences for ecosystems, as well as posing serious health hazards to living beings. Specifically, this work aimed to evaluate the ability of hemp (Cannabis sativa L.) plants to grow on a copper (Cu)-contaminated medium. In addition, the effectiveness of an environment-friendly treatment with sulfate in improving plant ability to cope with Cu-induced oxidative stress was also explored. Results showed that plants were able to grow at high Cu concentrations. Therefore, hemp could represent an interesting energy crop in Cu-contaminated soils. Although the response of Cu-treated plants was evidenced by the increase in thiol content, following modulation of sulfur metabolism, it remains to be clarified whether the use of exogenous sulfate could be an agronomic practice to improve crop performance under these edaphic conditions

Interaction Between Sulfur and Iron in Plants.

It is well known that S interacts with some macronutrients, such as N, P, and K, as well as with some micronutrients, such as Fe, Mo, Cu, Zn, and B. From our current understanding, such interactions could be related to the fact that: (i) S shares similar chemical properties with other elements (e.g., Mo and Se) determining competition for the acquisition/transport process (SULTR transporter family proteins); (ii) S-requiring metabolic processes need the presence of other nutrients or regulate plant responses to other nutritional deficiencies (S-containing metabolites are the precursor for the synthesis of ethylene and phytosiderophores); (iii) S directly interacts with other elements (e.g., Fe) by forming complexes and chemical bonds, such as Fe-S clusters; and (iv) S is a constituent of organic molecules, which play crucial roles in plants (glutathione, transporters, etc.). This review summarizes the current state of knowledge of the interplay between Fe and S in plants. It has been demonstrated that plant capability to take up and accumulate Fe strongly depends on S availability in the growth medium in both monocots and dicot plants. Moreover, providing S above the average nutritional need enhances the Fe content in wheat grains, this beneficial effect being particularly pronounced under severe Fe limitation. On the other hand, Fe shortage induces a significant increase in the demand for S, resulting in enhanced S uptake and assimilation rate, similar to what happens under S deficiency. The critical evaluation of the recent studies on the modulation of Fe/S interaction by integrating old and new insights gained on this topic will help to identify the main knowledge gaps. Indeed, it remains a challenge to determine how the interplay between S and Fe is regulated and how plants are able to sense environmental nutrient fluctuations and then to adapt their uptake, translocation, assimilation, and signaling. A better knowledge of the mechanisms of Fe/S interaction might considerably help in improving crop performance within a context of limited nutrient resources and a more sustainable agriculture

How Wind Turbines Alignment to Wind Direction Affects Efficiency? A Case Study through SCADA Data Mining

SCADA control systems are the keystone for reliable performance optimization of wind farms. Processing into knowledge the amount of information they spread is a challenging task, involving engineering, physics, statistics and computer science skills. The present work deals with the effects on the efficiency of turbine inability of optimal aligning to the wind direction, due to meandering wind caused by wakes. The approach is tested on a judiciously chosen cluster of turbines of a wind farm sited in southern Italy. By a post-processing method based on discretization of nacelle position measurements, a set of dominant patterns of the cluster is identified. The patterns associated to best performances are individuated and it is shown that they correspond to non-trivial alignment to wind direction

Interaction between Sulfate and Selenate in Tetraploid Wheat (Triticum turgidum L.) Genotypes

Selenium (Se) is an essential micronutrient of fundamental importance to human health and the main Se source is from plant-derived foods. Plants mainly take up Se as selenate (SeO42−), through the root sulfate transport system, because of their chemical similarity. The aims of this study were (1) to characterize the interaction between Se and S during the root uptake process, by measuring the expression of genes coding for high-affinity sulfate transporters and (2) to explore the possibility of increasing plant capability to take up Se by modulating S availability in the growth medium. We selected different tetraploid wheat genotypes as model plants, including a modern genotype, Svevo (Triticum turgidum ssp. durum), and three ancient Khorasan wheats, Kamut, Turanicum 21, and Etrusco (Triticum turgidum ssp. turanicum). The plants were cultivated hydroponically for 20 days in the presence of two sulfate levels, adequate (S = 1.2 mM) and limiting (L = 0.06 mM), and three selenate levels (0, 10, 50 μM). Our findings clearly showed the differential expression of genes encoding the two high-affinity transporters (TdSultr1.1 and TdSultr1.3), which are involved in the primary uptake of sulfate from the rhizosphere. Interestingly, Se accumulation in shoots was higher when S was limited in the nutrient solution

On the Possible Wind Energy Contribution for Feeding a High Altitude Smart Mini Grid

The use of renewable energy sources to increase electricity access, especially in remote areas as high mountains, is a possible contribution to poverty reduction, climate change mitigation and improved resilience. In this paper an evaluation of the wind potential of a remote area in Nepal is performed, using CFD methods and the simulation of a micro wind turbine projected by Perugia University. With an accurate analysis of wind data and air density effects it is possible to test energy production potential in areas with high average wind speed. The overall estimated production for each turbine is an interesting result and an easily exportable contribution to the perspective of sustainable development at very high altitudes and remote areas