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21.
Gabriella Di Lena Irene Casini Roberto Caproni Elena Orban 《Food Additives and Contaminants: Part B: Surveillance Communications》2018,11(3):175-182
This study investigated mercury contamination levels in eight commercially valuable crustacean species caught off the Central Adriatic and Tyrrhenian coasts of Italy. Total mercury levels were measured by Thermal Decomposition-Amalgamation-Atomic Absorption Spectrophotometry. Results showed a high variability among species with values ranging from 0.070 to 1.24 (mg kg?1 wet weight). The lowest mercury levels were detected in caramote prawn (Penaeus kerathurus), warty crab (Eriphia verrucosa) and European spider crab (Maja squinado), decapods living in shallow waters. Levels exceeding the limits established by the European Commission were found in species living in close contact with bottom sediments: deepwater rose shrimp (Parapenaeus longirostris), blue and red shrimp (Aristeus antennatus) and Norway lobster (Nephrops norvegicus). For shrimps, the inter-individual variability observed was mostly related to the body size, indicating the accumulation of mercury with age. An estimation of the human intake of mercury associated to the consumption of the crustaceans sampled and its comparison with the Tolerable Weekly Intake are provided. 相似文献
22.
Variations in yield and gluten proteins in durum wheat varieties under late‐season foliar versus soil application of nitrogen fertilizer in a northern Mediterranean environment 下载免费PDF全文
23.
Gian-Pietro Di Sansebastiano Silvia Fornaciari Fabrizio Barozzi Gabriella Piro Laura Arru 《International journal of molecular sciences》2014,15(3):4565-4582
We investigated the effect of auxin and acetylcholine on the expression of the tomato expansin gene LeEXPA2, a specific expansin gene expressed in elongating tomato hypocotyl segments. Since auxin interferes with clathrin-mediated endocytosis, in order to regulate cellular and developmental responses we produced protoplasts from tomato elongating hypocotyls and followed the endocytotic marker, FM4-64, internalization in response to treatments. Tomato protoplasts were observed during auxin and acetylcholine treatments after transient expression of chimerical markers of volume-control related compartments such as vacuoles. Here we describe the contribution of auxin and acetylcholine to LeEXPA2 expression regulation and we support the hypothesis that a possible subcellular target of acetylcholine signal is the vesicular transport, shedding some light on the characterization of this small molecule as local mediator in the plant physiological response. 相似文献
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Trace Elements in the Si Furnace-Part II: Analysis of Condensate in Carbothermal Reduction of Quartz
Elena Dal Martello Gabriella Tranell Oleg Ostrovski Guangqing Zhang Ola Raaness Rune Berg Larsen Kai Tang Pramod Koshy 《Metallurgical and Materials Transactions B》2013,44(2):244-251
Silicon feedstock for production of solar-grade silicon should be as pure as possible to decrease the cost of manufacturing of solar cells. Impurities in quartz, carbonaceous materials, electrodes, and refractories are mostly present in the form of oxides. These oxides can be reduced to volatile gaseous compounds in presence of SiO(g) and CO(g) atmosphere and potentially leave the furnace or stay in the condensed reaction products, metal, and slag. This work investigates the conditions under which volatile impurities report to the gas phase in laboratory experiments with lumpy and pelletized mixtures of SiO2, SiC, and Si at 1923 K and 2123 K (1650 °C and 1850 °C), respectively, were carried out. The volatile compounds were generated by the reduction of quartz and collected in the form of condensate. The effects of the reaction temperature, quartz type, charge composition, pellets, and lumps on the composition of the condensate were studied. The trace elements in the charge input, reacting charge, and condensate were analyzed using inductively coupled plasma (ICP)-mass spectroscopy (MS) and X-ray diffraction (XRD). CO(g) and SiO(g), which are the major components in reduction reactions, formed four types of condensate: white, brown, green, and orange. The condensate constituents were amorphous SiO2, 3C:SiC, Si, and α-quartz. Each impurity present in the quartz charge entered the gas phase during quartz reduction and was detected in the condensate. Al and Fe show limited volatility. The volatility of Mn, P, and B depends on the charge mix: a higher PCO enhances the concentration of these elements in the gas phase. Fluid inclusions, common in hydrothermal quartz, enhance the distribution of the contaminants to the gas phase. Industrial campaigns on Si and Fe-Si production confirm the experimental results. 相似文献
26.
Simonetta Caira Gabriella Pinto Valentin A. Balteanu Lina Chianese Francesco Addeo 《Food chemistry》2013
A novel genetic variant at the αs1-casein locus of water buffalo (WB), 8-residue shorter than its wild-type has been found and sequenced. The internal deletion of the peptide E35KVNELsT42 was confirmed by the isolation of the junction peptide. The 8-residue deletion mutant has a molecular weight that is 919 Da less than that of the wild-type. The novel isoform with a unique f35-42 deletion could be the result of the skipping of exon 6, generating an exon 6-deleted variant of αs1-casein. The wild-type and its shortened αs1-casein forms were found to co-exist in many individual milk samples. In contrast, the 8-residue, internally deleted αs1-casein variant did not occur in water buffaloes of the Mediterranean breed reared in Italy. Wild-type αs1-casein has 6 to 8 phosphate groups (P) while the internally deleted form 6 and 7P per molecule. 相似文献
27.
Emese Rka Blint Gabriella Fr Balzs Kui Zsolt Balla Eszter Sra Kormnyos Erik Mrk Orjn Brigitta Tth Gyngyi Horvth Edina Szcs Sndor Benyhe Eszter Ducza Petra Pallagi Jzsef Malth Viktria Venglovecz Pter Hegyi Lrnd Kiss Zoltn Rakonczay Jr. 《International journal of molecular sciences》2022,23(3)
Opioids are widely used for the pain management of acute pancreatitis (AP), but their impact on disease progression is unclear. Therefore, our aim was to study the effects of clinically relevant opioids on the severity of experimental AP. Various doses of fentanyl, morphine, or buprenorphine were administered as pre- and/or post-treatments in rats. Necrotizing AP was induced by the intraperitoneal injection of L-ornithine-HCl or intra-ductal injection of Na-taurocholate, while intraperitoneal caerulein administration caused edematous AP. Disease severity was determined by laboratory and histological measurements. Mu opioid receptor (MOR) expression and function was assessed in control and AP animals. MOR was expressed in both the pancreas and brain. The pancreatic expression and function of MOR were reduced in AP. Fentanyl post-treatment reduced necrotizing AP severity, whereas pre-treatment exacerbated it. Fentanyl did not affect the outcome of edematous AP. Morphine decreased vacuolization in edematous AP, while buprenorphine pre-treatment increased pancreatic edema during AP. The overall effects of morphine on disease severity were negligible. In conclusion, the type, dosing, administration route, and timing of opioid treatment can influence the effects of opioids on AP severity. Fentanyl post-treatment proved to be beneficial in AP. Clinical studies are needed to determine which opioids are best in AP. 相似文献
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Carlo Ricciardi Giancarlo Canavese Riccardo Castagna Gabriella Digregorio Ivan Ferrante Simone L. Marasso Alessandro Ricci Valentina Alessandria Kalliopi Rantsiou Luca S. Cocolin 《Food and Bioprocess Technology》2010,3(6):956-960
The micro- and nano-technologies coupled with a deep knowledge of organic/inorganic interfaces guarantee an exceptional sensitivity
and specificity of the sensor, while the lab-on-a-chip platform reduces assay times and limits sampling and/or sample preparation,
providing compact and portable objects. Therefore, the development of innovative biosensors such as antibody-immobilized microcantilevers
can overcome the evident limits of nowadays technologies, such as time consuming, expensiveness, difficult automation, low
sensitivity, accuracy, and precision for quantitative methods. The present study proposes two device designs for the detection
of food pathogens, exploiting an antibody-immobilized microcantilever biosensors, a novel class of mass detectors. For the
first one, we integrated the mechanical sensors on a microfluidic platform (lab-on-a-chip) to perform online analysis, directly
in liquid environment. We showed that our portable biosensors could easily detect the presence of pathogenic bacteria such
as Salmonella enterica serotype enteritidis in concentration 105 cfu/mL in just 40 min, without any enrichment and/or sample preparation. To increase the mass sensitivity of our analysis,
we also fabricated microstructures optimized for vibrating in vacuum environment. Using a dip-and-dry technique, we showed
that, in such configuration, the experimental limit of detection is as low as 103 cfu/mL. Due to the extremely small volumes needed, our biosensors operating in vacuum have the potentiality of detecting
the presence or absence of a single cell. 相似文献
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