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Metabolic state can alter olfactory sensitivity, but it is unknown whether the activity of the olfactory bulb (OB) may fine tune metabolic homeostasis. Our objective was to use CRISPR gene editing in male and female mice to enhance the excitability of mitral/tufted projection neurons (M/TCs) of the OB to test for improved metabolic health. Ex vivo slice recordings of MCs in CRISPR mice confirmed increased excitability due the targeted loss of Kv1.3 channels, which resulted in a less negative resting membrane potential (RMP), enhanced action potential (AP) firing, and insensitivity to the selective channel blocker margatoxin (MgTx). CRISPR mice exhibited enhanced odor discrimination using a habituation/dishabituation paradigm. CRISPR mice were challenged for 25 weeks with a moderately high-fat (MHF) diet, and compared with littermate controls, male mice were resistance to diet-induced obesity (DIO). Female mice did not exhibit DIO. CRISPR male mice gained less body weight, accumulated less white adipose tissue, cleared a glucose challenge more quickly, and had less serum leptin and liver triglycerides. CRISPR male mice consumed equivalent calories as control littermates, and had unaltered energy expenditure (EE) and locomotor activity, but used more fats for metabolic substrate over that of carbohydrates. Counter to CRISPR-engineered mice, by using chemogenetics to decrease M/TC excitability in male mice, activation of inhibitory designer receptors exclusively activated by designer drugs (DREADDs) caused a decrease in odor discrimination, and resulted in a metabolic profile that was obesogenic, mice had reduced EE and oxygen consumption (VO(2)). We conclude that the activity of M/TC projection neurons canonically carries olfactory information and simultaneously can regulate whole-body metabolism. SIGNIFICANCE STATEMENT The olfactory system drives food choice, and olfactory sensitivity is strongly correlated to hunger and fullness. Olfactory function thereby influences nutritional balance and obesity outcomes. Obesity has become a health and financial crisis in America, shortening life expectancy and increasing the severity of associated illnesses. It is expected that 51% of Americans will be obese by the year 2030. Using CRISPR gene editing and chemogenetic approaches, we discovered that changing the excitability of output neurons in the olfactory bulb (OB) affects metabolism and body weight stabilization in mice. Our results suggest that long-term therapeutic targeting of OB activity to higher processing centers may be a future clinical treatment of obesity or type II Diabetes.

The development of new materials based on abundant elements, reduced toxicity is today crucial for the next generation of energy device. Titanium-doped hydroxyapatite (TiHA) was tested for the first time as photoanode material for Dye – Sensitized Solar Cells (DSSCs). The chemical composition and energy structure of TiHA powders with increasing titanium content (5 wt%, 10 wt% and 15 wt%) were extensively characterized by surface electron spectroscopies, XPS and UPS. Their compatibility with conventional ruthenium-based dyes molecules was also assessed, producing considerable uptake. TiHA films were produced by screen-printing technique and XRD analyses confirm the presence of apatitic structure. The film properties were completely determined by optical, morphological (FE–SEM) and functional characterizations. Finally, TiHA-based DSSCs were assembled and their photovoltaic performance were assessed. The best efficiency, equal to 0.14%, was obtained for the TiHA containing 15 wt% of titanium. These results open the path for the possible application of doped hydroxyapatite as novel materials for energy conversion systems.

Titanium surface characteristics, including microtopography, chemical composition, and wettability, are essential features to achieve osseointegration of dental implants, but the choice of a particular surface topography is still a debated topic among clinicians. An increased level of implant surface hydrophilicity has been demonstrated to ameliorate osseointegration and shorten healing times. The aim of this work is to develop and test a suitable thermal-based method to enhance titanium surface wettability without modifying other characteristics of the implant surface. For this function, titanium discs with different surface topography have been thermally treated by testing different temperatures and excluding those that led to evident chromatic and morphological modifications. The selected surface gain in wettability after the treatment was assessed through contact angle measurement, chemistry modifications through x-ray photoelectron spectroscopy (XPS) analysis, and microtopography through scanning electron microscopy (SEM). Results showed a great enhancement in hydrophilicity on the tested surfaces without any other modification in terms of surface chemical composition and topography. A possible limitation of this method could be the persistent, although relatively slow, biological aging of the surfaces after the treatment. The present findings indicate that the described treatment could be a safe and effective method to enhance dental titanium hydrophilicity and thus its biological performance.

The differentiation therapy is focused on the identification of new agents able to impair the proliferative and metastatic potential of cancer cells through the induction of differentiation. Although several markers of cell differentiation on tumor cells have been identified, their causal relationship with neoplastic competence has not been characterized in sufficient detail to propose their use as new pharmacological targets useful for the design of new differentiation agents. Polyamine level in cancer cells and in body fluids was proposed as potential marker of cell proliferation and differentiation. The main advantage of this marker is the possibility to evaluate the antineoplastic activity of new drugs able to induce cell differentiation and consequently to inhibit tumor growth and metastasis. The presented report shows a simply and highly reproducible reverse-phase high-performance liquid chromatographic (HPLC) method for the determination of ortho-phthalaldehyde (OPA) derivatives of polyamines: putrescine (PUT), cadaverine (CAD), spermidine (SPD) and spermine (SPM). The novelty of this method is the fluorescence response for OPA-derivate of SPM, generally low in other procedures, that has been significantly improved by the use of a fully endcapped packing material with minimal silanol interactions. The limits of detection for PUT, CAD, SPD and SPM were 0.6, 0.7, 0.8, and 0.4 pmol/mL, respectively. The analysis time was ≤ 20 min, and the relative recovery rate was of about 97%. To verify the usefulness of this method, it has been validated in a murine melanoma cell line (B16-F10) treated with two theophylline derivatives (namely 8-chlorotheophylline and 8-bromotheophylline). These two compounds increased the activity of tissue transglutaminase (TG2) and the synthesis of melanin, two recognized markers of melanoma cell differentiation, and significantly reduced the levels of intracellular polyamines.

Molecularly imprinted polymeric nanogels (nanoMIPs) are soft biomimetics with recognition properties similar to antibodies but robustness and integrability to devices (sensing, assays) typical of polymers. Aiming at tailor-made at-will the recognition and physical properties of these biomimetics, we investigated the process of stamping analytes of clinical relevance, i.e. an idiotipic peptide of Troponin I, on protein-compatible soft-material at the nanoscale. Highly crosslinked poly(acrylamide-co-methacrylic acid) nanoparticles were prepared by precipitation polymerization via free radical initiation. The influence of the monomer composition to the nanogel hydrodynamic size was observed by dynamic light scattering and scanning electron microscopy. The effect of the total monomers to template (TM:T) molar ratio on the formation of the binding sites was investigated thermodynamically. Results indicate rules for the manipulation of the nanogel sizes, showing the pivotal role of hydrophobic interactions in confining the polymerization to the nanoscale (∼60 nm). The efficacy of the stamping process in the chosen polymerization conditions resulted maximal for TM:T molar ratios in the range 175:1–437:1. NanoMIPs with nanomolar dissociation constants for the template and a mean number of one binding site per particle were produced. Overall the results set conditions for preparing synthetic recognition nanoparticles acting as peptide-recognition elements.

A study leading to the development of a piezoelectric sensing device for environmental monitoring of aromatic micropollutants in water is reported. A Piezoelectric Quartz Crystal (PQC) was functionalized through electropolymerization of a quinoxaline cavitand, known to possess remarkable capabilities in selectively trapping aromatic compounds through multiple π-π and CH-π interactions. The obtained film was characterized via X-ray Photoelectron spectroscopy (XPS) to elucidate its chemical composition. The design and synthesis of the new quinoxaline cavitand functionalized at the upper rim with a bithiophene moiety suitable for electropolymerization is described. The molecular structure of the new receptor was elucidated via X-ray diffraction analysis. The performance of the obtained sensor towards selected chlorinated and not chlorinated hydrocarbons in water was tested. Excellent limit of detection (0.17 ppm), below the present stringent Italian value, was achieved for 1,2,4-trichlorobenzene, outperforming conventional systems. The frequencymetric sensor showed high reproducibility from independent functionalized PQCs, with RSD values lower than 5%.

Having single atoms or small clusters docked onto a single layer graphene represents a charming feature for energy-storage and catalysis. Unfortunately, the large cohesion energy of transition metals often prevents the isolation of nanoscopic clusters, which invariably tend to aggregate. The decoration of defective graphene layers with single Pt atoms and sub-nanometric clusters is herein achieved by exploiting metal carbonyl clusters, as precursor, and investigated by means of transmission electron microscopy and X-ray photoemission spectroscopy. Unexpectedly, the process of aggregation of Pt into larger clusters is inhibited onto the surface of defective graphene, where the Pt-clusters are found to fragment even into single metal atoms.

Soft molecularly imprinted nanogels (nanoMIPs), selective for human transferrin (HTR), were prepared via a template assisted synthesis. Owing to their soft matter, the nanoMIPs were observed to deform at binding to HTR: while no relevant changes were observed in the hydrodynamic sizes of HTR-free compared to HTR-loaded nanoMIPs, the HTR binding resulted in a significant increment of the nanoMIP stiffness, with the mean Young's modulus measured by AFM passing from 17 ± 6 kPa to 56 ± 18 kPa. When coupled to a plastic optical fibre (POF) plasmonic platform, the analyte-induced nanoMIP-deformations amplified the resonance shift, enabling to attain ultra-low sensitivities (LOD = 1.2 fM; linear dynamic range of concentrations from 1.2 fM to 1.8 pM). Therefore, soft molecularly imprinted nanogels that obey to analyte-induced deformation stand as a novel class of sensitivity-gain structures for plasmonic sensing.

Brain function relies on the ability of neural networks to maintain stable levels of activity, while experiences sculpt them. In the neocortex, the balance between activity and stability relies on the coregulation of excitatory and inhibitory inputs onto principal neurons. Shifts of excitation or inhibition result in altered excitability impaired processing of incoming information. In many neurodevelopmental and neuropsychiatric disorders, the excitability of local circuits is altered, suggesting that their pathophysiology may involve shifts in synaptic excitation, inhibition, or both. Most studies focused on identifying the cellular and molecular mechanisms controlling network excitability to assess whether they may be altered in animal models of disease. The impact of changes in excitation/inhibition balance on local circuit and network computations is not clear. Here we report findings on the integration of excitatory and inhibitory inputs in healthy cortical circuits and discuss how shifts in excitation/inhibition balance may relate to pathological phenotypes.

Robust cell adhesion is known to be necessary to promote cell colonization of biomaterials and differentiation of progenitors. In this paper, we propose the functionalization of Silicon Oxycarbide (SiOxCy) nanowires (NWs) with 3-mercaptopropyltrimethoxysilane (MPTMS), a molecule containing a terminal –SH group. The aim of this functionalization was to develop a surface capable to adsorb proteins and promote cell adhesion, proliferation and a better deposition of extracellular matrix. This functionalization can be used to anchor other structures such as nanoparticles, proteins or aptamers. It was observed that surface functionalization markedly affected the pattern of protein adsorption, as well as the in vitro proliferation of murine osteoblastic cells MC3T3-E1, which was increased on functionalized nanowires (MPTMS-NWs) compared to bare NWs (control) (p

Molecular switches enable the fabrication of multifunctional devices in which an electrical output can be modulated by external stimuli. The working mechanism of these devices is often hard to prove, since the molecular switching events are only indirectly confirmed through electrical characterization, without real-space visualization. Here, we show how photochromic molecules self-assembled on graphene and MoS2 generate atomically precise superlattices in which a light-induced structural reorganization enables precise control over local charge carrier density in high-performance devices. By combining different experimental and theoretical approaches, we achieve exquisite control over events taking place from the molecular level to the device scale. Unique device functionalities are demonstrated, including the use of spatially confined light irradiation to define reversible lateral heterojunctions between areas possessing different doping levels. Molecular assembly and light-induced doping are analogous for graphene and MoS2, demonstrating the generality of our approach to optically manipulate the electrical output of multi-responsive hybrid devices., Photochromic molecules offer the unique opportunity to demonstrate multifunctional devices with light-tunable electrical characteristics. Gobbi et al. build light-switchable electronic heterojunctions based on atomically precise, photo-reversible molecular superlattices on graphene and MoS2.

In this work we propose a realistic model of nanometer-thick SiC/SiOx core/shell nanowires (NWs) using a combined first-principles and experimental approach. SiC/SiOx core/shell NWs were first synthesised by a low-cost carbothermal method and their chemical-physical experimental analysis was accomplished by recording X-ray absorption near-edge spectra. In particular, the K-edge absorption lineshapes of C, O, and Si are used to validate our computational model of the SiC/SiOx core/shell NW architectures, obtained by a multiscale approach, including molecular dynamics, tight-binding and density functional simulations. Moreover, we present ab initio calculations of the electronic structure of hydrogenated SiC and SiC/SiOx core/shell NWs, studying the modification induced by several different substitutional defects and impurities into both the surface and the interfacial region between the SiC core and the SiOx shell. We find that on the one hand the electron quantum confinement results in a broadening of the band gap, while hydroxyl surface terminations decrease it. This computational investigation shows that our model of SiC/SiOx core/shell NWs is capable to deliver an accurate interpretation of the recorded X-ray absorption near-edge spectra and proves to be a valuable tool towards the optimal design and application of these nanosystems in actual devices.

In this work we propose a realistic model of nanometer-thick SiC/SiO x core/shell nanowires (NWs) using a combined first-principles and experimental approach. SiC/SiO x core/shell NWs were first synthesised by a low-cost carbothermal method and their chemical-physical experimental analysis was accomplished by recording X-ray absorption near-edge spectra. In particular, the K-edge absorption lineshapes of C, O, and Si are used to validate our computational model of the SiC/SiO x core/shell NW architectures, obtained by a multiscale approach, including molecular dynamics, tight-binding and density functional simulations. Moreover, we present ab initio calculations of the electronic structure of hydrogenated SiC and SiC/SiO x core/shell NWs, studying the modification induced by several different substitutional defects and impurities into both the surface and the interfacial region between the SiC core and the SiO x shell. We find that on the one hand the electron quantum confinement results in a broadening of the band gap, while hydroxyl surface terminations decrease it. This computational investigation shows that our model of SiC/SiO x core/shell NWs is capable to deliver an accurate interpretation of the recorded X-ray absorption near-edge spectra and proves to be a valuable tool towards the optimal design and application of these nanosystems in actual devices. © 2018 The Royal Society of Chemistry.

Cortical circuits are profoundly shaped by experience during postnatal development. The consequences of altered vision during the critical period for ocular dominance plasticity have been extensively studied in rodent primary visual cortex (V1). However, little is known about how eye opening, a naturally occurring event, influences the maturation of cortical microcircuits. Here we used a combination of slice electrophysiology and immunohistochemistry in rat V1 to ask whether manipulating the time of eye opening for 3 or 7 d affects cortical excitatory and inhibitory synaptic transmission onto excitatory neurons uniformly across layers or induces laminar-specific effects. We report that binocular delayed eye opening for 3 d showed similar reductions of excitatory and inhibitory synaptic transmission in layers 2/3, 4, and 5. Synaptic transmission recovered to age-matched control levels if the delay was prolonged to 7 d, suggesting that these changes were dependent on binocular delay duration. Conversely, laminar-specific and long-lasting effects were observed if eye opening was delayed unilaterally. Our data indicate that pyramidal neurons located in different cortical laminae have distinct sensitivity to altered sensory drive; our data also strongly suggest that experience plays a fundamental role in not only the maturation of synaptic transmission, but also its coordination across cortical layers.

The Hummers' method for graphite oxide (GO) preparation has been applied to graphite nanoplatelets, in order to achieve higher reaction yield and faster kinetics. Aqueous GO solutions have been used to produce uniform GO films on a polyethylene terephthalate substrate, generating graphene patterns in a controlled way (widths of a few tens of microns). The reduction of GO deposited on the polymeric substrate has been performed by using a Nd:YVO4 continuous-wave frequency-duplicated laser. Spectroscopic and diffractometric characterizations (FT-IR, visible-NIR, Raman, XPS, and XRD) have shown that the reduction process induced by the laser annealing technique is mainly due to dehydration of the GO layers. It has been obtained by means of a suitable laser optical apparatus, a controlled reduction of GO without damaging the substrate, and precise writing of micro-tracks that can be used as electrically and thermally conductive patterns.

Singlet oxygen has attracted great attention in physical, chemical, as well as biological studies, mainly due to its high reactivity and strong oxidising properties. In this context, hybrid nanosystems comprised of (inorganic) X-ray absorbing nanostructures and (organic) light-sensitive material (photosensitizers) can potentially overcome the limitations of visible light penetration in matter. A deep investigation of the interface of such hybrid nanosystems for X-ray induced generation of singlet oxygen is key to better understand the processes at the hybrid interface, and to control the energy transfer from inorganic to organic counterparts, which ultimately leads to enhanced singlet oxygen generation. Here, we demonstrate that SiC/SiOx core/shell nanowires functionalized with the tetrakis.pentafluorophenyl) porphyrin can act as a highly promising and viable strategy to generate singlet oxygen, making this novel hybrid nanosystem attractive for applications in photocatalysis and nanomedical applications. Using different excitation sources (i. e., electrons, visible light, and X-rays) our findings prove that SiC/SiOx core/shell nanowires show X-ray excited optical luminescence, and that optical emission of the photosensitizer is largely enhanced by the nanowires, yielding an efficient energy transfer. A consequent singlet oxygen production of the functionalized nanowires is demonstrated after X-ray excitation in a clinical linear accelerator. These findings will provide an insight in developing an effective route to the molecular functionalization of SiC/SiOx core/shell nanowires and their potential use as singlet oxygen generators.

The optical band gap energy and the electronic processes involved are important parameters of a semiconductor material and it is therefore important to determine their correct values. Among the possible methods, the spectrophotometric is one of the most common. Several methods can be applied to determine the optical band gap energy and still now a defined consensus on the most suitable one has not been established. A highly diffused and accurate optical method is based on Tauc relationship, however to apply this equation is necessary to know the nature of the electronic transitions involved commonly related to the coefficient n. For this purpose, a spectrophotometric technique was used and we developed a graphical method for electronic transitions and band gap energy determination for samples in powder form. In particular, the n coefficient of Tauc equation was determined thorough mathematical elaboration of experimental results on TiO2 (anatase), ZnO, and SnO2. The results were used to calculate the band gap energy values and then compared with the information obtained by Ultraviolet Photoelectron Spectroscopy (UPS). This approach provides a quick and accurate method for band gap determination through n coefficient calculation. Moreover, this simple but reliable method can be used to evaluate the nature of electronic transition that occurs in a semiconductor material in powder form. (C) 2016 Elsevier B.V. All rights reserved.

We report the development of sol-gel derived TiO2 thin films with adjustable and defined properties suitable for memristive cell fabrication. Memristive cells were developed by the sol-gel deposition of titania onto SiO2/Ti/Pt engineered electrodes via spin coating, followed by diverse curing and annealing procedures. The influence of the processing conditions and the sol's chemical composition on the film properties, and therefore on the memristive response, was studied by micro-Raman and transmission spectroscopies, profilometry, ellipsometry, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and X-ray absorption and diffraction spectroscopies (XAS and XRD). A memristive response was acquired from a number of these cells, revealing a dependence of the electrical behavior on minor changes in the TiO2 structure, electroforming parameters, and architecture. Thus, these properties provide a handle for fine-tuning electrical performance.

We describe a procedure for the optimization of a 3C-SiC buffer layer for the deposition of 3C-SiC on (001) Si substrates. A 100 – 150 nm thick SiC buffer was deposited after a standard carbonization at 1125 °C, while increasing the temperature from 1125 °C to 1380 °C. Ramp time influenced the quality and the crystallinity of the buffer layer and the presence of voids at the SiC/Si interface. After the optimization of the buffer, to demonstrate its effectiveness, a high-quality 3C-SiC was grown, with excellent surface morphology, crystallinity and low stress.

A procedure for the optimization of a 3C–SiC buffer layer for the deposition of 3C–SiC/(001) Si is described. After a standard carbonization at 1125 °C, SiH 4 and C 3 H 8 were added to the gas phase while the temperature was raised from 1125 °C to the growth temperature of 1380 °C with a controlled temperature ramp to grow a thin SiC layer. The quality and the crystallinity of the buffer layer and the presence of voids at the SiC/Si interface are related to the gas flow and to the heating ramp rate. In order to improve the buffer quality the SiH 4 and C 3 H 8 flows were changed during the heating ramp. On the optimized buffer no voids were detected and a high-quality 1.5 μm 3C–SiC was grown to demonstrate the effectiveness of the described buffer.

Bulk defective graphene produced by thermal exfoliation of graphite oxide was treated under H-2 and investigated with X-ray photoemission spectroscopy, neutron spectroscopy, and solid state nuclear magnetic resonance. Graphene defects appear effective in dissociating H2 molecule and in promoting H covalent absorption on the carbon backbone. Measured generalized phonon density of states shows the presence of localized peaks ascribed to C H bending modes already in pristine graphene, whose intensities enhance when samples are treated under H2 at 1273 K. However, H-1 NMR evidences a thermally activated dynamics with a correlation time of a few microseconds assigned to a part of H atoms bound onto the graphene plane. These findings point toward a diffusive dynamics of the hydrogen chemically e, bound to graphene sheets, already active at room temperature.

Palladium nanoparticles are of great interest in many industrial fields, ranging from catalysis and hydrogen technology to microelectronics, thanks to their unique physical and chemical properties. In this work, palladium clusters have been prepared by reduction of [PdCl4]2−ions with ethylene glycol, in the presence of poly(N-vinyl-2-pyrrolidone) (PVP) as stabilizer. The stabilizer performs the important role of nucleating agent for the Pd atoms with a fast phase separation, since palladium atoms coordinated to the polymer side-groups are forced at short distances during nucleation. Quasispherical palladium clusters with a diameter of ca. 2.6 nm were obtained by reaction in air at 90°C for 2 hours. An extensive materials characterization by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and other characterizations (TGA, SEM, EDS-SEM, and UV-Vis) has been performed in order to evaluate the structure and oxidation state of nanopalladium.

The Sol-gel route is a versatile method to fabricate multi-layer, dense and homogeneous ZnO thin films with a controlled thickness and defects for a memristive application. In this work, sol-gel derived multi-layer undoped and Al-doped ZnO thin films were prepared by a spin-coating technique on SiO2/Ti/Pt and sil ica glass substrates. The effect of both Al doping and curing conditions on the structural and morphological features of ZnO films was investigated by complementary techniques, including electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, micro-Raman spectroscopy, and X-ray diffraction anal- ysis. Electrical measurements were performed on SiO2/Ti/Pt/ZnO/Pt(dishes) and SiO2/Ti/Pt/ZnO(Al)/Pt(dishes) fabricated memristive cells and preliminary current-voltage curves were acquired.

High kinetic energy impacts between inorganic surfaces and molecular beams seeded by organics represent a fundamental tool in materials science, particularly when they activate chemical–physical processes leading to nanocrystals' growth. Here we demonstrate single-layer graphene synthesis on copper by C60 supersonic molecular beam (SuMBE) epitaxy. A growth temperature down to 645 °C, lower than that typical of chemical vapour deposition (1000 °C), is achieved by thermal decomposition of C60 with the possibility of further reduction. Using a variety of electron spectroscopy and microscopy techniques, and first-principles simulations, we describe the chemical–physical mechanisms activated by SuMBE and assisted by thermal processes, resulting in graphene growth. In particular, we find a role of high kinetic energy deposition in enhancing the organic/inorganic interface interaction and controlling the fullerene cage openings. These results, while discussed in the specific case of graphene on copper, are potentially extendible to different metallic or semiconductor substrates and where lower processing temperature is desirable.

SummarySynaptic responses are generally studied in the absence of spontaneous spiking, contrasting with the situation in the intact brain. A new study shows that even small increases in spontaneous network firing can significantly affect the properties and dynamics of excitatory evoked response in sensory neocortex.

Long-term synaptic potentiation (LTP) is thought to be a key process in cortical synaptic network plasticity and memory formation. Hebbian forms of LTP depend on strong postsynaptic depolarization, which in many models is generated by action potentials that propagate back from the soma into dendrites. However, local dendritic depolarization has been shown to mediate these forms of LTP as well. As pyramidal cells in supragranular layers of the somatosensory cortex spike infrequently, it is unclear which of the two mechanisms prevails for those cells in vivo. Using whole-cell recordings in the mouse somatosensory cortex in vivo, we demonstrate that rhythmic sensory whisker stimulation efficiently induces synaptic LTP in layer 2/3 (L2/3) pyramidal cells in the absence of somatic spikes. The induction of LTP depended on the occurrence of NMDAR (N-methyl-d-aspartate receptor)-mediated long-lasting depolarizations, which bear similarities to dendritic plateau potentials. In addition, we show that whisker stimuli recruit synaptic networks that originate from the posteromedial complex of the thalamus (POm). Photostimulation of channelrhodopsin-2 expressing POm neurons generated NMDAR-mediated plateau potentials, whereas the inhibition of POm activity during rhythmic whisker stimulation suppressed the generation of those potentials and prevented whisker-evoked LTP. Taken together, our data provide evidence for sensory-driven synaptic LTP in vivo, in the absence of somatic spiking. Instead, LTP is mediated by plateau potentials that are generated through the cooperative activity of lemniscal and paralemniscal synaptic circuitry.

In this paper, we report on the fabrication of N,N'-1H,1H-perfluorobutil dicyanoperylenediimide (PDIF-CN2) organic thin-film transistors by Supersonic Molecular Beam Deposition. The devices exhibit mobility up to 0.2 cm(2)/V s even if the substrate is kept at room temperature during the organic film growth, exceeding by three orders of magnitude the electrical performance of those grown at the same temperature by conventional Organic Molecular Beam Deposition. The possibility to get high-mobility n-type transistors avoiding thermal treatments during or after the deposition could significantly extend the number of substrates suitable to the fabrication of flexible high-performance complementary circuits by using this compound. (C) 2014 AIP Publishing LLC.

Photodynamic Therapy (PDT) is a therapeutical approach in the cancer treatment, which consists in the activation of a photosensitizer (phorphyrins) with visible light in order to produce singlet oxygen, to exert a cytotoxic activity towards cancer cells. The use of visible light limits the PDT application only to shallow deseases, for this reason we propose a new "X­Ray induced PDT" approach, using nanohybrid systems as photosensitizer, consisting in Silicon Carbide (SiC) nanowires (NWs) functionalized with organic molecules (fluorinated porphyrins). Modification of the inorganic semiconductor surface with organic or bio­molecules represents the route to activate processes at the interface and can be achieved by functionalizing the SiC NWs with porphyrins, that showing a good match between the organic absorption Q band and the 3C­SiC near­band­edge­optical emission. In fact SiC NWs have interesting light emission properties [1] so it is promising the idea to couple this light emission with an organic absorber showing strong fluorescence properties, a viable route to increase the optical emission efficiency as well as to promote the anchoring of biological groups. We demonstrated the functionalization of SiOx/SiC core shell NWs, grown by a carbothermal method, showing enhanced fluorescence, with fluorinated porphyrins H2TPP(F) by supersonic molecular beam deposition (SuMBD), an approach that can promote and activate chemical/physical processes at the interface by means of the organic precursor kinetics properties [2]. The H2TPP(F)/SiC­NWs system has been deeply investigated in­situ with surface photoelectron spectroscopy and ex­situ by Cathodoluminescence (CL) to clarify the growth kinetics at low coverages and the interface processes. Results concerning the core level (C1s, Si2p, N1s, F1s) analysis at different growth steps on planar oxidized surface and SiOx/SiC core shell NWs will be presented. The role of morphology of inorganic surfaces together with kinetic activation of H2TPP(F) molecules in molecular beams will be discussed.

In this paper, we discuss the surface doping in sexithiophene (T6) organic field-effect transistors by PDI-8CN2. We show that an accumulation heterojunction is formed at the interface between the organic semiconductors and that the consequent band bending in T6 caused by PDI-8CN2 deposition can be addressed as the cause of the surface doping in T6 transistors. Several evidences of this phenomenon have been furnished both by electrical transport and photoemission measurements, namely the increase in the conductivity, the shift of the threshold voltage and the shift of the T6 HOMO peak towards higher binding energies., 5 pages, 5 figures

The growth of SiO x nanowires (NWs) with intense white emission is reported. Due to carbon monoxide gas being used as a dopant precursor, carbon-doped under-stoichiometric silicon dioxide NWs are obtained. The doping of the NWs is studied by means of x-ray photoelectron spectroscopy, which allows to assess the presence of carbon atoms in the silicon oxide amorphous structure. The light emission properties are studied by means of cathodoluminescence spectroscopy, which shows three main emission bands set at 2.7 eV (blue), 2.3 eV (green) and 1.9 eV (red), resulting in the white emission.

In sensory systems, peripheral organs convey sensory inputs to relay networks where information is shaped by local microcircuits before being transmitted to cortical areas. In the olfactory system, odorants evoke specific patterns of sensory neuron activity which are transmitted to output neurons in olfactory bulb glomeruli. How sensory information is transferred and shaped at this level remains still unclear. Here we employ mouse genetics, 2-photon microscopy, electrophysiology and optogenetics, to identify a novel population of glutamatergic neurons (VGLUT3+) in the glomerular layer of the adult mouse olfactory bulb as well as several of their synaptic targets. Both peripheral and serotoninergic inputs control VGLUT3+ neurons firing. Furthermore, we show that VGLUT3+ neurons photostimulation in vivo strongly suppresses both spontaneous and odor-evoked firing of bulbar output neurons. In conclusion, we identify and characterize here a microcircuit controlling the transfer of sensory information at an early stage of the olfactory pathway.