THz time-domain spectroscopy of mixed CO2–CH3OH interstellar ice analogs

The icy mantles of interstellar dust grains are the birthplaces of the primordial prebiotic molecular inventory that may eventually seed nascent solar systems and the planets and planetesimals that form therein. Here, we present a study of two of the most abundant species in these ices after water: carbon dioxide (CO2) and methanol (CH3OH), using TeraHertz (THz) time-domain spectroscopy and mid-infrared spectroscopy. We study pure and mixed-ices of these species, and demonstrate the power of the THz region of the spectrum to elucidate the long-range structure (i.e. crystalline versus amorphous) of the ice, the degree of segregation of these species within the ice, and the thermal history of the species within the ice. Finally, we comment on the utility of the THz transitions arising from these ices for use in astronomical observations of interstellar ices

Analysis of geochemical tracers in different systems soil-Citrus limon (L.) Osbeck

Today is increasing the attention of consumers for the origin of food and high reputation of products with a distinct geographical identity. Food traceability is an important issue in food safety and quality control, with impacts on food security, its quantity and overall availability. The knowledge of a chemistry relationship between the soil and the agricultural products is an important tool for the quality assessment of food. Citrus Limon is the most important fruit tree crop in the world and the detection of potential fraud could improve by using tools linking the chemistry composition of this production to its typical growing area. This study use rare earth elements (REEs) as geochemical tracers. The REEs are a set of 14 elements, from lanthanum to lutetium that can be divided in light rare earth elements (LREEs), from La to Gd and heavy rare earth elements (HREEs), from Tb to Lu. The REEs have recognized as very useful tracers due to their generally coherent and predictable behavior. The aim of the research is to observe whether the fruits of various cultivars of citrus cultivated on the same soil and their products (fruit and juice) reproduce the same distribution of REEs. Taking into account of our previous works carried out on grapevine – soil system [1, 2], we applied the same technique to evaluate and trace the REEs distribution in soil– Citrus Limon fruits system. Ten different varieties of Lemon fruits (Citrus limon Osbeck (L.)) were sampled. Lemon plant were grafted onto an unique rootstock (Citrus × aurantium L.), grown on volcanic soil in two experimental farms, located at the "Acireale" region (latitude 37 ° 37'23 N, longitude 15° 09'51.00 E and 205 m a.s.l., in Sicily, Italy) and “Portici” region (latitude 40 ° 81' 55 N, longitude 14° 34'75.00 E and 75 m a.s.l., in Campania, Italy). The varieties selected were: Akragas, Erice, Selinunte, Segesta, Continella, Femminello Siracusano, Femminello Dosaco, Kamarina, Sfusato, Ovale di Sorrento, Interdonato. A sample of 2 kg of fruit was collected at technological ripeness from each plant of three for every cultivar. As well as, three soil samples (about 2 kg) in the field corresponding to lemon sampling were collected and to reduce any surface contamination from a depth of 10–30 cm. The REEs amount, the HREEs/LREEs relations and their distribution in the fruit and citrus juice with respect to the own soil were determined and calculated. Results obtained were treated with statistical methods. The intriguing results obtained with a geochemical approach are the first on the soil–Citrus Limon fruits system

Preliminary studies of geochemical tools to traceability of Sicilian honey

Today is increasing the attention of consumers for the origin of food and high reputation of products with a distinct geographical identity. Food traceability is an important issue in food safety and quality control, with impacts on food security, its quantity and overall availability. Furthermore, the possibility of tracing the origin of foodstuff is assuming an increasingly important role at the legislative level, as a tool that may allow to prove on product authenticity and to control adulteration So, establish systems to trace food or feed products through specified stages of production, processing and distribution play a key role also to ensure food safety. For these reason, in the last years, a various of analytical techniques have been tested to found ways to establish the geographical origin of different kinds of food and many works reported that the combination of different analytical methods associated a multifactorial analysis of the data seems to be the most promising system to establish univocal traceability systems. Despite, the honey is a well appreciated natural product in the world and the detection of potential fraud could be favored through tools linking the chemistry composition of this production to producing area. A relatively small number of investigations regarding traceability of honey can be found in the scientific literature. Therefore, in these contest the development of fingerprinting techniques based on the determination of the specific markers of provenance analyzed whit chemometric approach represents an interesting area of research. Recent works have been demonstrated the potentiality of the study of the distribution patterns of rare earth as a promising analytical method for traceability of food products due coherent and predictable chemical behaviour of these compounds. Also, have been demonstrated that their distribution in soil keeps unaltered in plants growing on that soil and eventually in agricultural products obtained from those plants and through the normalization of the REEs distribution, it is possible to appreciate their relative enrichments in soil-plant- agro food products The aim of the research is to observe if the REEs normalizated pattern of honey is kept unaltered respect the soils of production to establish a correlation between geographic area and honey product. In this first study the REE approach, give very intriguing results in the geographical traceability of honey samples. The results have been supported by statistical treatment. A larger study is in progress to optimize the analytical methodology and to extend the research to a major number of sample for a better geographical characterization

f-zpd algebras and a multilinear Nullstellensatz

Let $f=f(x_1,\dots,x_m)$ be a multilinear polynomial over a field $F$. An $F$-algebra $A$ is said to be $f$-zpd ($f$-zero product determined) if every $m$-linear functional $\varphi\colon A^{m}\rightarrow F$ which preserves zeros of $f$ is of the form $\varphi(a_1,\dots,a_m)=\tau(f(a_1,\dots,a_m))$ for some linear functional $\tau$ on $A$. We are primarily interested in the question whether the matrix algebra $M_d(F)$ is $f$-zpd. While the answer is negative in general, we provide several families of polynomials for which it is positive. We also consider a related problem on the form of a multilinear polynomial $g=g(x_1,\dots,x_m)$ with the property that every zero of $f$ in $M_d(F)^{m}$ is a zero of $g$. Under the assumption that $m<2d-3$, we show that $g$ and $f$ are linearly dependent

Effects of Citrus essential oils on weed emergence and on soil microorganisms

Weed invasion is a major problem for agricultural productivity since causes economic and environmental damages. Weed control can be achieved through chemical, mechanical, biological and cultural means. Although synthetic herbicides are effective for weed control, they have a negative impact on soil and the environment. Therefore, it is important to develop alternative means that are in the meanwhile effective and ecofriendly. EOs are commonly used for bactericidal, virucidal, fungicidal, antiparasitical, insecticidal, medicinal and cosmetic applications. Citrus EOs are the most widely used in the world for many purposes. Moreover, some studies have recently investigated their potential as herbicides. EOs can be extracted in different ways among which hydro distillation and cold pressing are commonly used. The two methods are based on different procedures. Hydro distillation is carried out with a Clevenger-apparatus that conducts the distillation process by boiling, condensing and decantation to separate the EOs. The cold pressing consist of crushing and pressing the peels thus leading to the formation of a watery emulsion. Then, the emulsion is centrifuged to separate out the EOs. Since no external substance are needed, this process ensures that the resulting EOs retains all their properties. The aim of this work was to evaluate the in vivo potential effects of Citrus EOs extracted by hydro distillation and cold pressing on weed emergence and on soil biochemical properties. The topsoil (5 cm) of an Inceptisol within the campus of University of Palermo was used for the experiment. 500 g of soil, air-dried and sieved at 1 cm, were used to fill each of the 24 aluminium pots (10 x 20 cm). then, soils were brought up to 100% of their water holding capacity (WHC) by adding firstly 150 mL of tap water (2/3 of WHC) followed by 70 mL of tap water (1/3 of WHC), by a anual sprayer, containing 8 mL L-1 of each one of the extracted EOs. Then, the soils were maintained at 50% of their water holding capacity during all the period of the experiment. Fitoil was used as emulsifier at a concentration of 1 ml L-1. Soils without EO, and with or without Fitoil, were considered as control. After one month the soils were moistened, plant biomass and height, and soil chemical and biochemical properties were evaluated. The experiment was carried out in quadruplicate to investigate the soil proprieties. In this work, the results are showed and discussed

long term administration of low doses of mycotoxins in poultry 1 residues of ochratoxin a in broilers and laying hens

Abstract The occurrence and amount of residues of ochratoxin A (OA) in poultry tissues and organs were investigated in a trial aimed at measuring the effects of contamination approaching the patterns more frequently found in natural situations (i.e., small doses of OA in the diet for long periods). Hubbard male broilers and laying hens were treated with an OA-contaminated feed (50 ppb) from the 14th day of age onward. Both groups were further divided into subgroups, some of which underwent continual treatment (64 and 169 days, respectively) and others that were withdrawn from administration (maximum 28 and 82 days, respectively). Determination of residues was performed by high performance liquid chromatography. Residues in liver were higher in broilers (up to 11.0 ppb) than in hens (1.5 ppb), whereas the reverse occurred in kidney (up to .8 and 5.8 ppb, respectively). Residues (.8 ppb) were also in hen thigh muscle but not in breast muscle. Residues of OA in poultry appear to be of possible public health concern. Suggestions for monitoring are given

Improvement of physical, chemical and biochemical proprieties of a salt affected Alfisol by addition of biochar and gypsum

Salinization is one of the major environmental problems threatening agricultural productivity. Soil salinization is defined as an excessive accumulation of salts within the soil profile. It negatively affects soil physical and chemical properties, as well as the biochemical ones. Reclamation of salt affected soils requires removal of soluble salts and Na+ from the soil exchange sites. Subsequently, salts are leached out the root zone by irrigation water when available. Gypsum (CaSO4·2H2O) is the most commonly used chemical amendment for reclamation of salt affected soils since it provides Ca2+ that replaces Na+ on the exchange sites and improves soil structure. Also organic amendments have been considered, but not extensively studied, for reclamation of salt affected soils. Recent studies have reported that biochar can be rich in nutrients like Ca2+ and Mg2+ and may enhance their availability in soil when added as amendment. Therefore, addition of biochar to a salt affected soil could aid in its remediation by supplying Ca2+ and Mg2+, and replacing Na+, improving aggregate stability and hydraulic conductivity. The objective of this study was to evaluate the effects of gypsum and biochar for the reclamation of a saline-sodic soil on some physical, chemical and biological properties. The topsoil of an Alfisol, about fifty meters far from the foreshore in the Petrosino coast (Sicily, Italy), was used for this experiment. The soil was air-dried and sieved at 2 mm. The main physical and chemical properties of the soil were: pH 7.3, clay 23 %, total carbonates 50.9 %, electrical conductivity 0.81 dS m-1 (1:5, w/v), total organic C 11.0 g kg-1, cation exchange capacity 24.8 cmol(+) kg-1, exchangeable sodium percentage 35 %. Two doses of gypsum (2.6 and 5.1 g kg-1 of soil) and two doses of biochar (4.2 and 8.3 g kg-1) were tested. The two doses of gypsum were calculated in order to decrease ESP from 35% to 25% and to 15%, respectively, whereas biochar was added in order to achieve an amount of 10 and 20 Mg ha-1. Following addition of gypsum and biochar, either alone or in combination, 100 g of soil were incubated at room temperature in 150 mL plastic pots and maintained at 50% of soil water holding capacity during all the duration of the experiment (22 days). One week after the incubation, three horse-radish seeds were sown. Then, after 13 days, plants were removed, oven dried at 60°C for 48 hours and weighed. The soils were analyzed to determine porosity, CEC, ESP, ECe, microbial biomass C, soil respiration and microbial community structure. The experiment was carried out in octuplicate. In this work, the results are reported and discusse

ATR-FTIR chemical screening for adulterants and sugar characterisation in honeys

The search for improvements in honey analysis is an important topic due to the relevance that adulterations and variations of sugar composition have in this food. Attenuated Total Reflectance Fourier Transform InfraRed spectroscopy (ATR-FTIR) is a reliable and fast analytical instrumentation for analysis of liquids, semi-solids and solids, which is currently used in food chemistry for qualitative and quantitative investigations. This work is aimed to build a fast analytical method, using ATR-FTIR and Partial Least Square (PLS) chemometric tool, to quantitative determination of glucose, fructose and sucrose present in honeys. We analyzed 25 honeys from Trentino and Sicily and a significant spectral range from the whole ATR-FTIR spectra were selected. Then a PLS multivariate calibration model was built by using mixtures of glucose, fructose and sucrose at various concentration. Samples for cross-validation were selected, thereby allowing quantitative evaluation of glucose, fructose and sucrose in all samples. Furthermore, a representative number of honeys were mixed with common adulterant syrups to simulate adulteration procedures and to verify the reliability of the ATR-FTIR technique in recognizing them. Preliminary results revealed not only the quantitative reliability of ATR-FTIR spectroscopy in the evaluation of sugars in honeys, but also its ability in recognizing honey adulteration