Box Behnken design-based optimized extraction of non-dioxin-like PCBs for GC-ECD and GC-MS analyses in milk samples

Abstract A multivariate optimization process of the sample extraction procedure by Box-Behnken design through a global desirability function is described for the determination of six non-dioxin-like polychlorinated biphenyls (NDL-PCBs # 28, 52, 101, 153, 138 and 180) in milk by GC-ECD and mass spectrometry. Three factors were involved in refining the extraction conditions: the acetone percentage in the extraction mixture, the sample/solvent ratio, and the extraction time. The three-factor design required 26 experiments that were carried out in duplicate and in a randomized order to minimize the bias effects of uncontrolled variables. The optimized factors (acetone percentage: 30%; sample-to-solvent ratio: 0.11 g mL−1; extraction time: 45 min) ensured a low solvent consumption and a reduced extraction time, allowing a rapid and simultaneous preparation of multiple sample extracts. The method was validated according to the European directives (Decision 657/2002/EC, SANTE 2017/11813/EC) through the evaluation of linearity, selectivity, LOD, LOQ, recovery, precision, and ruggedness

Hermetia illucens (L.) (Diptera: Stratiomyidae) Odorant Binding Proteins and Their Interactions with Selected Volatile Organic Compounds: An In Silico Approach

The black soldier fly (BSF), Hermetia illucens (Diptera: Stratiomyidae), has considerable global interest due to its outstanding capacity in bioconverting organic waste to insect biomass, which can be used for livestock, poultry, and aquaculture feed. Mass production of this insect in colonies requires the development of methods concentrating oviposition in specific collection devices, while the mass production of larvae and disposing of waste may require substrates that are more palatable and more attractive to the insects. In insects, chemoreception plays an essential role throughout their life cycle, responding to an array of chemical, biological and environmental signals to locate and select food, mates, oviposition sites and avoid predators. To interpret these signals, insects use an arsenal of molecular components, including small proteins called odorant binding proteins (OBPs). Next generation sequencing was used to identify genes involved in chemoreception during the larval and adult stage of BSF, with particular attention to OBPs. The analysis of the de novo adult and larval transcriptome led to the identification of 27 and 31 OBPs for adults and larvae, respectively. Among these OBPs, 15 were common in larval and adult transcriptomes and the tertiary structures of 8 selected OBPs were modelled. In silico docking of ligands confirms the potential interaction with VOCs of interest. Starting from the information about the growth performance of H. illucens on different organic substrates from the agri-food sector, the present work demonstrates a possible correlation between a pool of selected VOCs, emitted by those substrates that are attractive for H. illucens females when searching for oviposition sites, as well as phagostimulants for larvae. The binding affinities between OBPs and selected ligands calculated by in silico modelling may indicate a correlation among OBPs, VOCs and behavioural preferences that will be the basis for further analysis

Hermetia illucens (L.) (Diptera: Stratiomyidae) Odorant Binding Proteins and Their Interactions with Selected Volatile Organic Compounds: An in Silico Approach

From MDPI via Jisc Publications RouterHistory: accepted 2021-09-07, pub-electronic 2021-09-11Publication status: PublishedThe black soldier fly (BSF), Hermetia illucens (Diptera: Stratiomyidae), has considerable global interest due to its outstanding capacity in bioconverting organic waste to insect biomass, which can be used for livestock, poultry, and aquaculture feed. Mass production of this insect in colonies requires the development of methods concentrating oviposition in specific collection devices, while the mass production of larvae and disposing of waste may require substrates that are more palatable and more attractive to the insects. In insects, chemoreception plays an essential role throughout their life cycle, responding to an array of chemical, biological and environmental signals to locate and select food, mates, oviposition sites and avoid predators. To interpret these signals, insects use an arsenal of molecular components, including small proteins called odorant binding proteins (OBPs). Next generation sequencing was used to identify genes involved in chemoreception during the larval and adult stage of BSF, with particular attention to OBPs. The analysis of the de novo adult and larval transcriptome led to the identification of 27 and 31 OBPs for adults and larvae, respectively. Among these OBPs, 15 were common in larval and adult transcriptomes and the tertiary structures of 8 selected OBPs were modelled. In silico docking of ligands confirms the potential interaction with VOCs of interest. Starting from the information about the growth performance of H. illucens on different organic substrates from the agri-food sector, the present work demonstrates a possible correlation between a pool of selected VOCs, emitted by those substrates that are attractive for H. illucens females when searching for oviposition sites, as well as phagostimulants for larvae. The binding affinities between OBPs and selected ligands calculated by in silico modelling may indicate a correlation among OBPs, VOCs and behavioural preferences that will be the basis for further analysis

Experimental evaluation of 3D ultrasound Palmprint recognition techniques based on curvature methods and under skin principal lines

In this work, two procedures to extract 3D Palmprint features from a 3D ultrasound image of the human palm are presented and experimentally evaluated by using a database composed of 172 samples from 71 different users. Appreciable recognition results were found

Three-dimensional ultrasound palmprint recognition using curvature methods

Palmprint recognition systems that use three-dimensional (3-D) information of the palm surface are the most recently explored techniques to overcome some two-dimensional palmprint difficulties. These techniques are based on light structural imaging. In this work, a 3-D ultrasound palmprint recognition system is proposed and evaluated. Volumetric images of a region of the human hand are obtained by moving an ultrasound linear array along its elevation direction and one by one acquiring a number of B-mode images, which are then grouped in a 3-D matrix. The acquisition time was contained in about 5 s. Much information that can be exploited for 3-D palmprint recognition is extracted from the ultrasound volumetric images, including palm curvature and other under-skin information as the depth of the various traits. The recognition procedure developed in this work is based on the analysis of the principal curvatures of palm surface, i.e., mean curvature image, Gaussian curvature image, and surface type. The proposed method is evaluated by performing verification and identification experiments. Preliminary results have shown that the proposed system exhibits an acceptable recognition rate. Further possible improvements of the proposed technique are finally highlighted and discussed

3-D Ultrasound Palmprint Recognition System Based on Principal Lines Extracted at Several Under Skin Depths

In recent years, several palmprint recognition procedures that use 3-D information on the palm surface have been proposed in order to overcome some limitations of 2-D palmprint. However, 3-D optical images provide information on the external skin surface only. Ultrasound waves have the capability to penetrate into human tissue and, therefore, can provide new kinds of 3-D information from acquired palmprints. In this paper, a 3-D ultrasound palmprint recognition system that accounts for principal line depth is proposed. It exploits several 2-D palmprints, extracted at different under skin depths with a classic procedure, opportunely combined to achieve a 3-D template. An ad hoc matching criterion is then defined in order to account for line depth information when comparing 3-D templates. Experiments of both verification and identification, performed on a homemade database, have shown that the 3-D recognition procedure exhibits very good recognition rates. The proposed 3-D technique also benefits from other advantages of ultrasound, including not being sensitive to many kinds of surface contaminations and its capability to detect liveness during the acquisition phase, which makes it very difficult to counterfeit

An improved ultrasound system for biometric recognition based on 3D Palmprint

In the present work, an improved ultrasound system for biometric recognition based on 3D Palmprint is proposed and experimentally validated. The system exploits an ultrasound gel pad, placed between the palm of the hand and the probe, as coupling medium, which is practical and non-invasive in real applications. Volumetric images of a region the palm of the hand were acquired and then post elaborated to provide 3D and 2D renderings. The recognition procedure is based on the fusion of a couple of 2D Palmprint images at two different under skin depths. A procedure for extracting main features from the fused image was established and a database composed by 315 samples from 63 volunteers was created. Identification experiments were performed to evaluate system performances. Results have shown the effectiveness of the proposed approach