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International audience; The present work aims to study the effects that acute exposure to low concentrations of silver nanoparticles (AgNPs) cause in digestive glands of terrestrial isopods (Porcellio scaber). The experiments were designed to integrate different analytical techniques, such as transmission electron microscopy, atomic absorption spectroscopy, proton induced X-ray emission, and Fourier transform IR imaging (FTIRI), in order to gain a comprehensive insight into the process from the AgNPs’ synthesis to their interaction with biological tissues in vivo. To this aim, terrestrial isopods were fed with AgNPs having different shapes, sizes, and concentrations. For all the tested conditions, no toxicity at the whole organism level was observed after 14 days of exposure. However, FTIRI showed that AgNPs caused detectable local changes in proteins, lipids, nucleic acids and carbohydrates at the tissue level, to an extent dependent on the interplay of the AgNPs’ properties: shape, size, concentration and dissolution of ions from them.

Fourier-Transform Infrared microspectroscopy, a largely used spectroscopic technique in basic and industrial researches, offers the possibility to analyze the vibrational features of molecular groups within a variety of environments. In the bioclinical field, and, in particular, in the study of cells, tissues and biofluids, it could be considered a supporting objective technique able to characterize the biochemical processes involved in relevant pathologies, such as tumoral diseases, highlighting specific spectral markers associable with the principal biocomponents (proteins, lipids and carbohydrates). In this article, we review the applications of infrared spectroscopy to the study of tumoral diseases of oral cavity compartments with the aim to improve understanding of biological processes involved during the onset of these lesions and to afford to an early diagnosis. Spectral studies on mouth, salivary glands and oral cystic lesions, objectively discriminate normal from dysplastic and cancer states characterizing also the grading.

Melatonin is an important hormone for the synchronization of the reproductive response to appropriate environmental conditions in photoperiodic animals. Even if a large amount of scientific evidences supports its positive impact on oocyte quality and fertilization rate, the biochemical processes involved are not completely understood. Fourier transform infrared (FT-IR) imaging technique has been applied to analyze the variations induced by melatonin administration on both growth and maturation phases of zebrafish oocytes. Chemical maps were acquired on thin ovary sections, from which average spectra were extracted for each class of oocytes. All average spectra were submitted to multivariate analysis, that separated them into different clusters according to oocyte class and treatment. The vibrational analysis highlighted modifications both in the proteic pattern, with an increment in helical structures with respect to β-sheets (amide I and II bands), and in the aliphatic chains and phosphate moieties for oocytes deriving from melatonin treated females. In addition, real time-PCR and enzyme-linked immunosorbent assay (ELISA) analyses showed that the administration of this hormone favoured the synthesis of vitellogenin. The reduction in gene expression involved in preventing oocyte maturation, such as bone morphogenetic protein ( bmp15 ) and transforming growth factor ( tgfβ1 ), was also observed together with the increase of the luteinizing hormone receptor ( lhr ), involved in the induction of oocyte maturation.

The aim of this study was to verify the effects of probiotic Lactobacillus rhamnosus on zebrafish oocyte maturation using FPA (focal plane array) FTIR imaging together with specific biochemical assays (SDS-PAGE, real-time PCR and enzymatic assay). Oocyte growth is prevalently due to a vitellogenic process which consists of the hepatic synthesis of vitellogenin and its selective uptake during maturation. The administration of L. rhamnosus IMC 501 for 10 days induced chemical changes to oocyte composition, promoting the maturation process. Some interesting biochemical features, linked to protein secondary structure (amide I band) and to phospholipidic and glucidic patterns, were detailed by vibrational analysis. The spectro- scopic results were supported by the early increase of the lysosomal enzyme involved in the final oocyte maturation, the cathepsin L. This enzyme increases during follicle maturation, with the highest levels in class IV oocytes. In treated females, class III oocytes showed higher cathepsin L gene expression and enzymatic activity, with levels comparable to class IV oocytes isolated from controls; this can be related to the proteolytic cleavage of the higher molecular mass yolk protein components, as evidenced by SDS-PAGE.

Zebrafish oocytes growth causes relevant modifications in protein components; in fact, the proteolytic cleavage of vitellogenin, a large sex-specific phospholipoglycoprotein synthesized in the female liver, leads to three main yolk protein components (phosphovitin and lipovitellins 1, 2), present as a complex in the oocyte. FT-IR Microspectroscopy could have the potentiality of monitoring these biochemical changes during the maturation process. Representative spectra for I–II, IIIA, IIIB and IV classes oocytes (Hierarchical Clustering Analysis and Principal Component Analysis) were investigated to find specific vibrational patterns corresponding to different maturation degrees. On going from I–II to IV class oocytes, relevant spectral differences were found with III class exhibiting an intermediate spectroscopic behaviour. In particular, the increase of the convoluted band at 2925 cm−1 (CH2 and CH3 stretching modes), as well as of intensity band ratios at 2926/2954 cm−1 (νasym CH2/CH3), 2854/2873 cm−1 (νsym CH2/CH3) and 1452/1392 cm−1 ( δ CH 2 / 3 / ν sym COO - ), suggest longer lipidic chains; broadening of Amide I and II bands and absorptions at 1737 (νC O, phospholipids) and 1157 cm−1 (νC O and νC OH carbohydrates) in lipovitellin and vitellogenin spectra, are present in III and IV classes.

Microimaging Fourier transform infrared spectroscopy is able to monitor differentiation between normal and malignant tissues. All the specimens, previously submitted to histological analysis, displayed abnormal spectra compared with the corresponding normal tissues with changes in many diagnostic bands like those arising from phosphate, C–O and CH stretching vibrational modes. The comparison between cancer (K) and connective (C) spectra evidenced the following differences: in the v CH region 3000–2800 cm −1 no hypomethylation effect was evident in K; the convolution of the bands of connective indicated an expected higher membrane fluidity; in the neoplastic zone, Amide I and II modes showed convoluted bands with maxima at 1651 and 1547 cm −1 , respectively, indicating an α-helix conformation of proteins due to changes in the secondary structure proteins upon carcinogenesis. Other signature bands, such as the deformation O–P–O phosphate band at 965 cm −1 , suggested DNA conformational changes in solid cancer, infiltrating cancer and neoplasia in the region 1350–800 cm −1 . These characteristic bands have been monitored as a function of the degree of cancer progression. Chemometric methods, such as principal component analysis (PCA) and hierarchical clustering analysis (HCA) have been used in order to distinguish spectra of neoplastic and normal zones.

Micro-imaging infrared spectroscopy has been performed on atheromatous plaques in order to localize and characterize substances responsible for the cytotoxic effects that prevent macrophages clearance of lipidic and calcified materials. In plaques with different graded atherosclerotic lesions, infrared determinations allowed to visualize gruel and ceroid toxic components and variously calcified zones. Compare correlations let to visualize the progression of the lesion on going from the lumen to the outer media of the plaque.

The new lipid 1,2-O-dioleyl-3-O-{2-[(12-crown-4)-methoxy]-ethyl}-sn-glycerol, 12C4L, has been synthesized. This molecule can coordinate different cations that should make the corresponding liposome a good candidate as vector of genetic material for possible applications in gene therapy. An important feature of the molecule is the possibility to modulate the net surface charge of their complexes with metal cations, which is important to provide efficient DNA transfections. The molecule and its complexes with some metal cations (Mg2+, Ca2+, Mn2+) have been characterized by FT-IR spectroscopy and band attributions confirmed by Density Functional Theory calculations. The net surface charge has been determined by Z potential determinations.

FT-IR microimaging was performed on colon tissues with the aim to characterize spectral ‘markers’ to distinguish healthy from pathological tissues. Evidences of spectral peculiarities were mainly found in the finger print region even in the presence of a low grade adenocarcinoma. The occurrence of inflammation and necrotic states can also be demonstrated. Through statistical analysis as well as custom map procedures it was possible to reconstruct the topological distribution of different biochemical states and to verify results from the histopathological analysis. Preliminary results from FT-NIR analysis are in substantial agreement with those in the mid infrared region.

Biomolecular profiling with Fourier-Transform InfraRed Microscopy was performed to distinguish the Zn2+-mediated effects on the crustacean (Porcellio scaber) digestive glands from the ones elicited by the ZnO nanoparticles (NPs). The exposure to ZnO NPs or ZnCl2 (1500 and 4000 µg Zn/g of dry food) activated different types of metabolic pathways: some were found in the case of both substances, some only in the case of ZnCl2, and some only upon exposure to ZnO NPs. Both the ZnO NPs and the ZnCl2 increased the protein (∼1312 cm−1; 1720–1485 cm−1/3000–2830 cm−1) and RNA concentration (∼1115 cm−1). At the highest exposure concentration of ZnCl2, where the effects occurred also at the organismal level, some additional changes were found that were not detected upon the ZnO NP exposure. These included changed carbohydrate (most likely glycogen) concentrations (∼1043 cm−1) and the desaturation of cell membrane lipids (∼3014 cm−1). The activation of novel metabolic pathways, as evidenced by changed proteins’ structure (at 1274 cm−1), was found only in the case of ZnO NPs. This proves that Zn2+ are not the only inducers of the response to ZnO NPs. Low bioavailable fraction of Zn2+ in the digestive glands exposed to ZnO NPs further supports the role of particles in the ZnO NP-generated effects. This study provides the evidence that ZnO NPs induce their own metabolic responses in the subtoxic range.

High resolution holographic polymer dispersed liquid crystal gratings are photo-induced periodic structures commonly affected by shrinkage. This phenomenon represents a problem in several application fields such as in high density optical storage. In this work we observed that, by directly monitoring the blue-shift of the reflection peak of the periodic structure, an evident shrinkage reduction occurs using the nitroxide radical Tinuvin770- N -yloxy [(bis(2,2,6,6-tetramethyl-piperidine-1-yloxy-4-yl)-sebacate] as inhibitor of polymerization. This compound is a stable hindered amine light stabilizer-derived free radical, which plays a significant role in the photo-polymerization dynamics.

In the field of the renewable energy exploitation, it is often at disposal the possibility to obtain electric power along small waterways, with values between 10 and 150 kW (micro hydro). For such cases one of the most suitable solution is the one which provides as hydromechanics turbine a cochlea, which was used in the past mainly for water pumping plants; the described solution is often indicated as Archimedes Screw Generator (ASG). Such a technical solution is more and more frequently adopted for economical reasons, and present a very large application field, with the possibility to exploit situations otherwise not convenient; an ASG provides normally an induction generator directly connected to the mains. After a short description of the mentioned systems and of their working principle, the proposal of the adoption of a frequency converter drive between the induction generator and the mains is discussed under both the technical and economical point of view.

Objective To characterize from a vibrational point of view the alterations caused by aging on human oocytes. Design Reproductive biology. Setting Private assisted reproductive technology clinic, synchrotron beam line, and university infrared laboratory. Patient(s) Twenty women of different ages (30 ± 2 and 39 ± 2 years) selected on the basis of detailed inclusion criteria and submitted to controlled ovarian stimulation according to a specific protocol. Intervention(s) Collection of 68 supernumerary oocytes that were not used during the IVF cycle from the above cited consenting patients. Main Outcome Measure(s) Focal Plane Array Fourier transform infrared (FTIR) analysis of human oocytes. Result(s) Specific spectral differences were highlighted in the two experimental groups of oocytes. In particular, in oocytes of 39-year-old women, the occurrence of peroxidative processes and a decrease in the amount of carbohydrates were observed, together with alterations in the phospholipid membrane, proteic pattern, and nucleic acids content. Conclusion(s) For the first time, FTIR spectroscopy was applied to human oocytes, leading to strong evidence of damage from aging in the gametes of mature women, which could be related to a decline in reproductive function. All the information obtained may be considered useful to improve the scientific knowledge on human reproduction and to exploit new strategies for detecting oocyte aging.

The principle of the universal field oriented (UFO) controller, operating in an arbitrary reference frame, is applied to a CRPWM inverter. Due to its high degree of generality,the UFO controller is compatible with rotor, stator, and air-gap flux field oriented control. The authors compare the stability regions and the steady state performance of these three types of controllers applied to the same machine. The rotor flux based controller has been selected as the basic reference. Digital simulation results are carried out to show that the performance of the complete UFO system, i.e., combined direct and indirect UFO, in a nonrotor flux based reference frame leads to a robust high performance drive with no dependency on machine parameters in steady state. >

In this paper, a new series of Logging-while-drilling (LWD) nuclear magnetic resonance (NMR) tools is introduced. The tools incorporate a magnet arrangement which provides a low field gradient minimizing adverse lateral motion effects. T2 distributions are measured while drilling or sliding in a range of hole sizes, including large holes previously inaccessible to LWD NMR measurements. Benefits and trade-offs of key tool design features are presented. Emphasis is placed on measurement quality, operational simplicity and log quality control in real time and memory mode through example logs from operator wells. Real-time T2 distributions provided by the new generation LWD NMR tool enable a full range of NMR answers, including lithology-independent total porosity, bound fluid volume and permeability. Real-time log quality controls monitor tool noise, antenna sensitivity, tuning quality and lateral motion. Acquisition sequences are optimized for porosity precision and accuracy in different environments. Drilling data have been acquired in several operator wells and a test well covering diverse ranges of formations and logging conditions. Environmental factors affecting porosity precision and T2 quality are discussed with reference to log quality indicators and comparison with wireline NMR logs is made where available. In general, the LWD tools deliver NMR answers comparable to the analogous wireline logs in terms of precision, accuracy and vertical resolution. With increased industry focus on LWD services and heightened sensitivity to downhole chemical sources, the need for reliable LWD NMR measurements continues to grow. In addition to a sourceless porosity measurement, NMR provides unique quantitative information on the disposition of producible fluids, which is not available from other logs. Real-time producibility information can be used to optimize formation pressure measurements and sampling as well as for timely completions and well placement decisions. The new generation LWD NMR tools introduced here addresses this need.

The adoption of Permanent Magnets in small brushless machines for automotive applications is becoming frequent. Some research on bonded magnets is being carried on to substitute the ferrites. In the paper the parallel and radial magnetizations are considered: the different process complexity levels are analyzed and the effects on the iron losses and the energetic performances are evaluated by means of a simulation analysis and its experimental validation.

The main aim of this paper is the analysis of the effects of various processing conditions on the magnetic, mechanical, and energetic properties of mixture systems consisting of insulated iron powder compound and aluminum alloy. Specimens with a different green density (obtained with compacting pressures of 400, 600, and 800 MPa) were treated in different atmospheres (in air and nitrogen), all implying a step at the maximum temperature of 500°C for 30 min. The microstructure analyses revealed that heat treatment of aluminum alloys has proven to be more effective when carried out in full nitrogen atmosphere, both in terms of bonding evolution between adjacent particles and magnetic properties. Experimental results in terms of magnetic properties, mainly iron loss, confirmed the potentialities of powder metallurgy in electromagnetic applications.

This study aimed to investigate the effects of two different doses (100 nM (M1) and 1 µM (M2)) of exogenous melatonin on the reproductive capacity of Fundulus heteroclitus. Eight days of melatonin exposure significantly increased the fecundity and embryo survival of F. heteroclitus only in the M2 group compared with the control; the hatching rate was unaffected. Moreover, increases in the local expression of the melatonin receptor (mtnr) gene during follicle maturation were found; however, there were no differences between the experimental groups. Furthermore, in vitro melatonin-treated follicles showed a significantly higher germinal vesicle break down percentage compared with the control, while SDS–PAGE showed no difference in the electrophoretic pattern of the major yolk proteins. Nevertheless, densitometry revealed a greater intensity of the 118-, 95- and 40-kDa components in groups treated with melatonin. Finally, Fourier transform infrared microspectroscopy was applied to classify the different stages of oocyte development (Stages I–II, III and IV) on the basis of their macromolecular composition. The effects induced by melatonin on oogenesis were investigated by comparing vibrational spectra of females exposed to melatonin with those of controls. Changes to the Amide I band, corresponding to an increase in β-structure, were found in oocytes of females exposed to the highest melatonin dose. These results highlight the positive role of melatonin, which is able to enhance the reproductive capacity of F. heteroclitus. Further studies are in progress to better explain the molecular mechanisms by which melatonin treatment affects reproduction in this marine species.

Abstract A successful exploration campaign has been achieved using innovative concepts and top technology. The results of the last two years are proving the success of this work philosophy marking a new era for Brazilian Petroleum Industry. In this scenario, the first horizontal producer well was drilled in albian carbonate reservoirs of Quissamã Member (Macaé Formation), anticipating reservoir dynamic understanding and the development phase. Since traditional logs could not capture the textural differences characterizing the most prolific zones, formation evaluation and geosteering challenges were addressed using new Logging While Drilling Technology. Differentiating measurements were Nuclear Magnetic Resonance (NMR), Spectroscopy and high-resolution images. An S shape pilot well was first drilled to identify target zones, establish potential layers and identify water/oil contact. A sideway horizontal well section was consequently drilled navigating through the intervals with best porosity/permeability properties and open fractures. To best benefit from real time data availability and to guarantee drilling efficiency, a full time monitoring and decision team was assembled in the well owner's headquarters, receiving streaming data from the rig. The Real Time NMR properties allowed evaluation of Net-to-Gross and reservoir quality; images were used to compute dips and adjust borehole inclination and effective porosity was determined using neutron/density and spectroscopy. Memory Data Formation Evaluation was performed using Multi-Mineral petrophysical analysis further supported by Neural Networks, trained using a data subset with NMR permeability and free fluid as targets and spectroscopy channels as input. The method was validated and applied with success over the complete horizontal section. Indication of movable fluids using NMR information was compared to the water fractions computed with independent methods (resistivity and sigma) leading to the conclusion that all water was irreducible along the wellbore. Testing this methodology in this first successful well founded the basis for effective formation evaluation of the complex shallow water carbonates in Brazil and will be used systematically in the upcoming wells. Introduction A field development project with horizontal wells, supported by limited appraisal drilling, requires a variety of high quality data for reservoir evaluation to guarantee success. Carbonate reservoirs involve extra challenges for horizontal well placement due to their depositional complexity and diagenetic susceptibility. Matrix density (and consequently porosity), rock texture, structural features (faults and open or closed fractures), pore connectivity and permeability cannot be characterized with enough precision only using a traditional log suite, composed of gamma ray, resistivity, neutron, density and sonic. To decrease the level of formation uncertainty and drilling risks, a cost effective solution is to include advanced measurements like magnetic resonance (NMR), resistivity/ultrasonic images and spectroscopy (ECS) in the evaluation plan.

This study has been undertaken to investigate spectral features of cystic lesions of the jaw with the aim to understand their tumoral progression and to evidence initial signals of neoplastic changes. Three important groups (according to the World Health Organization classification) representing inflammatory (radicular) and developmental (orthokeratinized odontogenic, OOC) cysts as well as keratocystic odontogenic tumor (KCOT) of the jaw have been studied by microimaging infrared spectroscopy. From the spectral data analysed with the multivariate pattern recognition procedure, representative spectra were isolated and used to build correlation maps to localize the biochemical components in the tissue. The procedure enabled to better understand spectral features of these classes of cysts and to discriminate tumoral from non-tumoral spectra through the analysis of ‘vibrational markers’. In KCOT, the correlation of calcium derivatives (in metaplastic or displastic bones) with the tumor has been highlighted, too. The distribution of various biochemical components in the tissues, achieved through correlation maps of representative spectra, resulted in satisfactory agreement with the histopathological analysis. ‘Spectral isolation’ of micro tumorigenic zones in some normal OOC cysts, demonstrated the potentiality of infrared spectroscopy to evidence the early stage of a hidden lesion.

Stem cells are a promising source in a wide range of medical fields, included bone tissue regeneration. In this study, we investigated the molecular structure of dental pulp stem cells (DPSCs), during their differentiation towards the osteoblastic phenotype. DPSCs, easily achievable even from human young adults, were isolated from dental pulp of included third molar teeth and then cultured with appropriate medium to induce osteoblast differentiation. The FT-IR analysis of undifferentiated and differentiated DPSCs well pin-pointed biological changes during the osteogenic differentiation, above all in the Amide I, II and III vibrational modes as well as in the phosphate stretching vibrations. The spectroscopic study was supported by reverse transcriptase-polymerase chain reaction (RT-PCR) for the expression of specific osteoblastic markers, such as type I collagen (Coll-I), alkaline phosphatase (ALP), osteocalcin (OCN) and runt-related transcription factor 2 (RUNX2).

In PM machines with curve shaped magnets the magnetization can have parallel or radial direction. The paper aims to evaluate the impact on the motor characteristics of magnetization direction, by means of simulation and experimental results. The proposed analysis is based on two different magnets technologies: one technology is industrially well established (anisotropic ferrite), while the other one is unconventional (rare-earth powder with phenolic resin bonded magnets). The case study is based on fractional horse power motor for electro-fan automotive applications: a concentrated windings fractional slots PM machine with external rotor.

The general problem of increasing, through the use of bonded magnets, the performances of small PM machines adopting ferrite magnets is analyzed; the general aim is the realization of motor prototypes adopting a structural solution of actual interest. After preliminary consideration some machine prototypes have been realized. The problem has been approached with the substitution of ferrite magnets with bonded ones. Different reasons brought the authors to the decision to produce some types of the necessary magnets in the internal laboratories. After an important preliminary analysis two types of bounded magnet have been selected, one of them not mentioned in the literature. Through the self produced magnets prototypes a preliminary simulation activity has been carried out, based of obtained real magnetic characteristics that brought to product different machines prototypes to test. The obtained results, allow to define very satisfactory the possible performance increment, and suggest to continue the research line.

The combined effect of trehalose and temperature on the wetting properties of L-alpha-dioleoyl-phosphatidyl-choline (DOPC) model membranes in excess aqueous solutions has been analyzed by X-ray diffraction and extended electron density map reconstruction. At room temperature, DOPC in excess water forms a fluid lamellar L(alpha) phase. In the presence of trehalose, no phase transitions occur, but repeat and intermembrane distances increase considerably. Electron density maps show that trehalose in solution promotes a straightening of the hydrocarbon chain packing and a reduction of the molecular average area at the polar-apolar interface. Accordingly, the increased intermembrane distance is interpreted as a clear indication of a sugar screening effect of the van der Waals attractive contribution in the lamellar stacks, which overcomes the eventual decreasing of the repulsive fluctuations due to the hardening of the bilayer. By contrast to the thermally induced membrane swelling observed in excess water, in the presence of trehalose the DOPC bilayer thickness and repeat and intermembrane distances decrease continuously with temperature. While the thermal dependence of bilayer thickness is a consequence of the chain conformational disorder promoted by temperature, the changes in the intermembrane distance can be explained only assuming a trehalose-induced re-setting of the long-range force balance. The final results confirm the complex mechanism by which trehalose stabilize lipid bilayers.