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Three field trials were conducted in central California in 1999 to assess the effects of transplant production and handling practices on yield, crop maturity, and fruit quality of processing tomato (Lycopersicon esculentum Mill.). For each trial, transplants of `Halley' tomato were obtained from a variety of commercial greenhouse transplant growers and subjected to various conditioning treatments during the week prior to planting. These treatments included N and/or P fertilization, varying temperature exposure or degree of water stress, or storage in the dark for 2 days before transplanting to simulate shipment from greenhouse to field. Nine transplant treatments (combinations of transplant source and conditioning treatment) were evaluated in each trial, with five 30 m long single-row plots per treatment arranged in a randomized complete-block design. Plots were mechanically harvested. Despite large differences among treatments in initial transplant characteristics (plant height, root cell volume, macronutrient content), there were no significant treatment differences in fruit yield in two trials; in the third trial, one treatment had significantly lower yield than the highest yielding treatment. In no trial were treatment differences in crop maturity (percent green fruit) or fruit quality (soluble solids content or juice color) significant. Across trials, the only transplant characteristic positively correlated with relative fruit yield (treatment yield/mean yield of that trial) was shoot P concentration, which varied among treatments from 1.3 to 11.7 g·kg–1.

Summary The relationship between rationalistic and intuitionistic styles of information processing and handedness was studied in 98 Ss who were asked to view videotapes of medical interns gambling and to determine solely on the basis of facial cues the amount of the payoff offered to each intern during a specific gambling trial. Two groups on the basis of the Ss' interpreting styles were defined: rationalistic Ss indicated that they used a systematic method to make the responses, intuitionistic Ss could not describe the rationale which they used to make their responses. No relationship was found between handedness and processing style or sex and processing style. Since handedness and processing style have been thought to be related to hemispheric dominance, this lack of relationship may suggest that hemispheric localization is not a highly specialized function.

Summary Interpretation of nonverbal facial cues was studied in two groups of male and female medical students, health-professionals, and undergraduates (N = 122). All Ss were asked to view videotapes of other students engaged in a learning task and to determine solely on the basis of facial clues the amount of monetary reward offered to a videotaped student during a specific learning trial. On the basis of the Ss interpreting styles, two groups were defined: (a) “Intellectuals” indicated that they used systematic trial-and-error methods to make their interpretations. Intellectuals needed several seconds to make a response and responded with greater accuracy under reinforced conditions. (b) “Intuitives” could not describe the rationale employed to make response choices. They responded instantaneously and more accurately under nonreinforced conditions. Both intuitive and intellectual groups were comprised of nearly equal numbers of male and female Ss. Overall accuracy was found to be independent of sex.

A greenhouse screening method for corky root (Pyrenochaeta lycopersici) resistance in the tomato (Lycopersicon esculentum) is described in detail. In determining the reliability of the method, known resistance sources within wild asccessions, commerical cultivars and breeding lines were evaluated for resistance in fields naturally infested with corky root and their response compared under greenhouse conditions in soil heavily infested with corky root and artifically maintained at temperatures between 10–13°C. The procedure developed can be used year round and improves the efficiency of recovering resistant progeny in large segregrating populations.

The authors present different antidotal strategies in treating phencyclidine (PCP) intoxication based upon specific symptomatic presentation. Evidence exists for dopaminergic, cholinergic and opiate-like activity of PCP in both laboratory and clinical studies. Reviewing these studies, clinical interventions are recommended according to various symptom clusters.

THE important problem of the security of industry in the United States must naturally be dealt with from a domestic viewpoint. It may, however, interest you to know how the Italian National Government has faced this problem, which was the most pressing one when Fascism took hold of the government after four years of almost constant insecurity of industry. I will try to present briefly the main features of the system, which is the result of studies carried on for several years and is set forth in several elaborate legal provisions.

Objective: To correlate blood transfusions and clinical outcomes during hospitalization in coronary artery bypass grafting surgery (CABG). Methods: Transfusion, clinical and hematological data were collected for 1,378 patients undergoing isolated or combined CABG between January 2011 and December 2012. The effect of blood transfusions was evaluated through multivariate analysis to predict three co-primary outcomes: composite ischemic events, composite infectious complications and hospital mortality. Because higher risk patients receive more transfusions, the hospital mortality outcome was also tested on a stratum of low-risk patients to isolate the effect of preoperative risk on the results. Results: The transfusion rate was 63.9%. The use of blood products was associated with a higher incidence of the three coprimary outcomes: composite infectious complications (OR 2.67, 95% CI 1.70 to 4.19; P

Phencyclidine (PCP) is a widely abused drug inducing a psychosis relieved by such dopamine antagonists as the neuroleptics. In the current study we compared two neuroleptics which act at different dopamine receptor sites. Haloperidol, a DA-2 receptor antagonist, and chlorpromazine, a DA-1 antagonist, were used to treat a total of 20 patients who experienced a phencyclidine psychosis. Ten patients each received two doses of one or the other neuroleptic on an alternating basis. Haloperidol 5 mg i.m. was shown to be superior to chlorpromazine 50 mg i.m. in relieving all signs of psychosis. The authors hypothesize that the DA-2 receptor is site-specific for PCP.

– In ten healthy subjects the trigemino-facial reflex was elicited by double shock (delta t = 0.5–1 s). The first stimulus was subliminal for pain and the second supramaximal for it. The percentage integral values, with respect to single shock, of the direct and consensual conditioned responses obtained in all subjects were averaged and compared with those conditioned by supramaximal stimuli for pain fibres. Significant differences between subliminal and supramaximal conditioning stimuli for pain fibres is revealed for only consensual R3 with delta t = 1 s: greater inhibition with painful stimuli. There were no significant differences in any of the other values. Our results show that a subliminal conditioning stimulus for pain threshold can inhibit the late responses to the test stimulus, both for R2 and especially for R3, suggesting that this mechanism can contribute to the trigeminofacial reflex habituation phenomenon.

Twenty male combinative cocaine free-base/phencyclidine (space-base) abusers were studied for forty-five days, in a double-blind design. Treatment with desipramine was significantly more effective than placebo in alleviating abstinence symptoms. This study tends to support the catecholamine-depletion hypothesis of cocaine and phencyclidine withdrawal.

An open field trial was conducted comparing desipramine and an active placebo in separate populations of chronic cocaine and phencyclidine (PCP) abusers, who discontinued their abuse. Subjects who received desipramine showed a decrease in depressive symptoms after a 20-40 day period regardless of whether they abused PCP or cocaine.

Volunteers (N=71) with premenstrual syndrome (PMS) were given the Peck-Abraham PMS Questionnaire and separated by resulting scores into mild, moderate, and severe groups. Fourteen subjects were randomly selected from each group. Pseudocholinesterase serum levels were measured on the first day of menses for all group members. Trait anxiety was measured by the State Trait Anxiety Inventory (STAI). Pseudocholinesterase, a possible marker for trait anxiety, was found elevated in 6 of 14 (43%) of the severe PMS subjects, in 2 of the 14 (14%) moderate PMS subjects, and in none of the mild PMS subjects. Trait anxiety was found in 8 of these subjects. None of the subjects with mild PMS showed trait anxiety, while 25% of those with moderate PMS and 75% of those with severe PMS showed trait anxiety. No subject with mild PMS had trait anxiety. In this study PMS is treated as a trait-dependent form of anxiety.

The presence of clinical and electromyographic (EMG) features of neuromuscular hyperexcitability (NMHE) and of the commonly associated neurovegetative disturbances (NVD) were investigated in 49 patients with primary fibromyalgia (PF) and in a control group of 33 patients with rheumatoid arthritis (RA). At least two clinical features of NMHE were present in 39%, and at least three NVD in 63% of PF patients. In contrast, only 1 RA control had two NMHE features (p greater than 0.005) and three NVD (p less than 0.001). Moreover, a significant post-ischemic spontaneous EMG hyperactivity was observed in 11 PF patients, and in only 1 control with RA (p less than 0.05). Finally, in patients with PF the number of tender points were correlated with psychological tests for depression (p less than 0.02), and the number of NVD. The present study shows that in patients with PF there is a large prevalence of NMHE complaints and NVD. The potential underlying pathogenetic mechanisms are also discussed.

Patients with phencyclidine psychosis were treated with two 50 mg injections of either chlorpromazine (N = 10) or meperidine (N = 10). The chlorpromazine-treated group responded more rapidly, but the meperidine-treated group had greater overall improvement. It is suggested that meperidine may have a role in the emergency treatment of phencyclidine psychosis. These findings may provide support for the hypothesis that dopaminergic psychosis is mediated by opioids.

The physician needs to know the signs, symptoms and recommended treatments of drug overdoses. Overdose of hallucinogens usually does not require drug therapy. Overdose of amphetamines ("uppers") may be complicated by the presence of PCP, a dissociative substance. It is important for the physician to be familiar with the street terminology for contemporary drugs of abuse and to be aware of how users obtain these drugs.

The relationship between premenstrual tension syndrome and dietary intake was studied in a population of 20 young adult women. Caloric intake was measured during the 10 days preceding and following the menstrual cycle. Those women with more severe symptoms recorded a greater increase in caloric intake. Caloric intake during the premenstrual period also increased with age. It is hypothesized that this caloric intake may be due to increased beta-endorphin levels.

M. G. Passarin, S. Monaco, S. Ferrari, C. Giannini, N. Rizzuto and G. Moretto (1996) Neuropathology and Applied Neurobiology 22, 60-67 Cytoskeletal changes in cultured human f ibroblasts following exposure to 2,5-hexanedione In the present study, the effects of the 2,5-hexanedione (HD) on the various cytoskeletal components of human eukaryotic cells were investigated. Primary cultures of human fibroblasts from three healthy donors were exposed to 2.8 mM HD for 14 days; unexposed cultures were used as controls. At different time intervals, cells were counted and the growth curves compared. After 14 days of treatment, the cultures were processed for immu-noblotting, immunocytochemistry and ultrastructural studies. As compared to controls, morphological abnormalities induced by HD consisted of modification of the cell shape, formation of tangles composed by 10 nm filaments and cytoplasmic segregation of microtubules and membrane-bound organelles. By immunocytochemistry, the tangles of cytoplasmic filaments were stained by an antibody specific for vimentin. By immunoblotting, the anti-vimentin antibody recognized only bands of 50-60 kDa. Comparison of growth curves between treated and control fibroblasts clearly revealed an interference of HD with the cell cycle. The present results demonstrate that the cytotoxicity of HD is not restricted to intermediate filaments, but affects other cytoskeletal components, such as microtubules, as suggested by the impairment of cell division cycle

We investigated two patients with the idiopathic hypereosinophilic syndrome and peripheral neuropathy. Clinical, EMG, and pathological findings were consistent with axonal polyneuropathy. Morphologic changes of the nerve biopsies suggested axonal damage secondary to increased endoneurial pressure from leakage of capillaries. We postulate that endothelial cell damage, followed by nerve edema, is the first step in the pathogenesis of peripheral neuropathy in these patients.

Fil: Galetto, Leonardo. Universidad Nacional de Córdoba. Córdoba, Argentina. Fil: Aizen, Marcelo A. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente. Rio Negro, Argentina. Fil: Arizmendi, María del Coro. Universidad Nacional Autónoma de México. México. Fil: Freitas, Breno M. Universidade Federal do Ceará. Brasil. Fil: Garibaldi, Lucas A. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Garibaldi, Lucas A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Giannini, Tereza C. Instituto Tecnológico Vale Desenvolvimento Sustentavel. Brasil. Fil: Lopes, Ariadna V. Universidade Federal de Pernambuco. Brasil. Fil: Do Espírito Santo, Mário M. Universidade Estadual de Montes Claros. Brasil. Fil: Maués, Márcia M. Embrapa Amazônia Oriental. Brasil. Fil: Nates-Parra, Guiomar. Universidad Nacional de Colombia. Colombia. Fil: Rodríguez, Jaime I. Museo Nacional de Historia Natural de Bolivia. Bolivia. Fil: Quezada-Euán, José J. G. Universidad Autónoma de Yucatán. México. Fil: Vandame, Remy. El Colegio de la Frontera Sur. México. Fil: Viana, Blandina F. Universidade Federal da Bahia. Brasil. Fil: Imperatriz-Fonseca, Vera L. Instituto Tecnológico Vale Desenvolvimento Sustentavel. Brasil. The conservation status of pollinators and pollination in Latin America (LA) is reviewed. The knowledge regarding native and managed pollinators (e.g., honeybee and stingless bees) and pollination services was synthetized, and the guidelines to improve the opportunities for conservation are provided, considering the threats to pollinators and the perspectives from traditional and local knowledge. The analysis indicates that diverse threats (e.g., large-scale agriculture, deforestation, overuse of agrochemicals) are linked with pollination and pollinator decline, which affect the reproduction of most native plants and the yields of many crops. LA harbours the highest bee diversity worldwide, with 26% of the total recorded species, and it is a biodiversity hotspot of vertebrate pollinators, including hummingbirds, perching birds, nectarivorous bats and other mammal pollinators. Specific recommendations to conserve native pollinators and to improve pollination services are provided, which could be considered by stakeholders and governments aiming to elaborate biocultural conservation. For example, introducing policies and legal responses for incentives to help farmers maintain natural habitats and forests, to replace or reduce agrochemicals and to improve diversified crop production with agroecological practices; refining agrochemical regulations to minimize the exposure of pollinators to insecticides and herbicides; improving knowledge and education on pollinators and pollination gives societies worldwide the opportunity to change current hegemonic agricultural practices and consumption paerns; integrating different land ethical views of ethnic minorities on a sustainable relationship between production and biodiversity. A wider view combining social, ecological, cultural dimensions may support beer decision making. This holistic socio-agroecological perspective is urgently needed to conserve and manage pollinators at different spatial and temporal scales, and to integrate pollination services, pollinator-friendly habitat management approaches and diversified farming systems. Se realizó una revisión sobre el estado de conservación de los polinizadores y la polinización en América Latina (LA). Se presentan pautas para mejorar las oportunidades de conservación, considerando las amenazas a los polinizadores y las perspectivas desde el conocimiento tradicional y local. El análisis indica que diversas amenazas (e.g., agricultura a gran escala, deforestación, uso excesivo de agroquímicos) están vinculadas con la disminución de polinizadores, afectando la reproducción de las plantas nativas y los rendimientos de muchos cultivos. LA alberga la mayor diversidad de abejas en todo el mundo y una gran diversidad de polinizadores vertebrados (e.g., colibríes, aves de percha nectarívoras, murciélagos nectarívoros y otros mamíferos). Se proporcionan recomendaciones para proteger los polinizadores nativos y mejorar los servicios de polinización, las que podrían ser consideradas por los tomadores de decisiones y así promover la conservación biocultural. Por ejemplo, desarrollar instrumentos legales, políticas e incentivos para ayudar a los agricultores a mantener los hábitats naturales, para reemplazar o reducir el uso de agroquímicos y para promover las prácticas agroecológicas; perfeccionar las reglamentaciones sobre aplicación de agroquímicos para minimizar la exposición de los polinizadores a insecticidas y herbicidas; mejorar la comunicación pública del conocimiento sobre los polinizadores y la polinización para incentivar un cambio en las prácticas agrícolas hegemónicas y los patrones de consumo actuales; considerar otras éticas ambientales de las minorías étnicas para enfatizar la necesidad de promover una relación sostenible entre producción de alimentos y biodiversidad. Se necesita urgentemente una visión más amplia que combine las dimensiones sociales, ecológicas y culturales para una mejor toma de decisiones. Esta perspectiva socio-agroecológica holística es importante para conservar y gestionar los polinizadores a diferentes escalas espaciales y temporales, y para poder integrar los servicios de polinización con enfoques de gestión del territorio favorables a los polinizadores y con sistemas agrícolas diversificados.

The present study is aimed at providing a brief overview of the Italian acidic waters based on literature and unpublished data. Acidic waters in Italy, as elsewhere, are relatively common and associated with extremely variable geological settings. Owing to their peculiar features, these waters may seriously affect the environment and the ecosystems. Along the Apennine belt, the western and inner sectors of the Italian peninsula record an anomalous geothermal gradient, mostly overlapping with the Neogene-to-present magmatism, that explains the presence of a huge amount of CO2(H2S)-rich gas and thermal water discharges, geothermal fields (e.g. Larderello and Mt. Amiata) and ore deposits (e.g. Fe- and polymetallic sulfides, e.g. Elba Island and Colline Metallifere). Acidic waters (pH ≤5) from volcanic and geothermal areas show outlet temperatures and Total Dissolved Solids (TDS) from 10 to 96°C and

An efficient microwave-assisted synthesis of TiO2:(B) nanorods, using titanium tetraisopropoxide (TTIP), benzyl alcohol as the solvent, together with boric acid and oleic acid as the additive reagents, has been developed. Chemical modification of TTIP by oleic acid was demonstrated as a rational strategy to tune the shape of TiO2 nanocrystals toward nanorod formation. The differently-shaped TiO2:(B) nanocrystals were characterized in detail by transmission electron microscopy (TEM), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and nitrogen absorption-desorption. Oleic acid coordinated on the nanocrystal surface was removed by the reduction of its carboxyl group, and the photocatalytic activity of bare TiO2 nanocrystals, under visible light irradiation, was also evaluated. The synthesized TiO2 anatase nanorods exhibited a good photoactivity and completely degraded Rhodamine B solution within three hours. - See more at: http://www.mdpi.com/2304-6740/2/2/264/htm#sthash.4UGNqXTd.dpuf

E' ancora possibile nel mondo contemporaneo 'ritrarre', rappresentare, i drammi della storia? Il saggio cerca di dimostrare quanto nel panorama attuale l'arte tenda a 'presentare' il problema piuttosto che rappresentarlo dal momento che il 'conflitto' nell'arte contemporanea sembra una componente intrinseca a molte manifestazioni artistiche attuali. Prendendo spunto dal palindromo (RAW WAR) di Bruce Nauman del 1970, il saggio attraversa la storia dell'arte contemporanea internazionale, a partire dal secondo dopoguerra fino all'epoca attuale, focalizzando l'attenzione su alcuni casi di studio. Molte produzioni artistiche recenti affrontano il tema scegliendo quella sorta di 'zona grigia' che separa, ma anche unisce, le vittime e i carnefici, che problematizza la relazione fra 'buoni' e 'cattivi' e denuncia la 'guerra' ponendo in una luce diversa le parti in conflitto, al di là della contrapposizione col 'nemico'.

A colloidal nonaqueous approach to semiconductor-magnetic hybrid nanocrystals (HNCs) with selectable heterodimer topologies and tunable geometric parameters is demonstrated. Brookite TiO(2) nanorods, distinguished by a curved shape-tapered profile with richly faceted terminations, are exploited as substrate seeds onto which a single spherical domain of inverse spinel iron oxide can be epitaxially grown at either one apex or any location along their longitudinal sidewalls in a hot surfactant environment. The topologically controlled arrangement of the component material lattices, the crystallographic relationships holding between them, and strain distribution across individual heterostructures have been studied by combining X-ray diffraction and absorption techniques with high-resolution transmission electron microscopy investigations. Supported by such structural knowledge, the synthetic achievements are interpreted within the frame of various mechanistic models offering complementary views of HNC formation. The different HNC architectures are concluded to be almost equivalent in terms of surface-interface energy balance associated with their formation. HNC topology selection is rationalized on the basis of a diffusion-limited mechanism allowing iron oxide heterogeneous nucleation and growth on the TiO(2) nanorods to switch from a thermodynamically controlled to a kinetically overdriven deposition regime, in which the anisotropic reactivity offered by the uniquely structured seeds is accentuated under high spatially inhomogeneous monomer fluxes. Finally, the multifunctional capabilities of the heterostructures are highlighted through illustration of their magnetic and photocatalytic properties, which have been found to diverge from those otherwise exhibited by their individual material components and physical mixture counterparts.

A surfactant-assisted nonaqueous strategy, relying on high-temperature aminolysis of titanium carboxylate complexes, has been developed to access anisotropically shaped TiO2 nanocrystals selectively trapped in the metastable brookite phase. Judicious temporal manipulation of precursor supply to the reaction mixture enables systematic tuning of the nanostructure geometric features over an exceptionally wide dimensional range (30-200 nm). Such degree of control is rationalized within the frame of a self-regulated phase-changing seed-catalyzed mechanism, in which homogeneous nucleation, on one side, and heterogeneous nucleation/growth processes, on the other side, are properly balanced while switching from the anatase to the brookite structures, respectively, in a continuous unidirectional crystal development regime. The time variation of the chemical potential for the monomer species in the solution, the size dependence of thermodynamic structural stability of the involved titania polymorphs, and the reduced activation barrier for brookite nucleation onto initially formed anatase seeds play decisive roles in the crystal-phase- and shape-tailored growth of titania nanostructures by the present approach.

Asymmetric binary nanocrystals (BNCs), comprising one c-axis elongated anatase TiO2 section and one gamma-Fe2O3 spherical domain attached together, are synthesized by heterogeneous nucleation of iron oxide onto the longitudinal facets of TiO2 nanorods in a ternary surfactant mixture. The topologically controlled composition of the BNCs is ascertained by a combination of powder X-ray diffraction, Raman and Mössbauer spectroscopy, high-angle annular dark-field imaging, and high-resolution transmission electron microscopy lattice fringe mapping, while their size-dependent magnetic behavior is demonstrated by ac susceptibility measurements. The heteroepitaxial growth proceeds through a mechanism never observed before for colloidal nanoheterostructures: the two domains share a restricted and locally curved junction region, which accommodates efficiently the interfacial strain and retards the formation of misfit dislocations. It is believed that these BNCs, which combine the properties of two technologically relevant oxide materials, can pave the way to reinforced applications in several fields of nanoscience, such as in photocatalysis, in malignant cell treatments, and in nanocrystal assembly.

Hydrophobically coated anatase TiO(2) nanorods can assist the reduction of AuCl(4) (-)ions at aqueous/nonpolar solvent interfaces, which results in the generation of organic-soluble Au nanoparticles with tunable size in the absence of any metal ligands and/or phase-transfer agents. The titania-nanorod-driven modulation of interfacial energy and catalysis of gold nucleation provide straightforward access to nanocomposite solutions of TiO(2)-stabilized Au nanoparticles. Among colloidal approaches, this method represents a unique tool for the surfactantless, large-scale preparation of nanostructured semiconductor-metal hybrid systems with relevant technological potential in catalysis, photocatalysis, and charge-storage processes.

Shape- and phase-controlled ZnSe nanocrystals are synthesized in hot mixtures of long-chain alkylamines and alkylphosphines. The variation in the rate of precursor addition, down to low and controlled levels, allows the nucleation, as well as the growth of the nanocrystals, to switch between the wurtzite and the zinc blend structures. Such a level of control leads to a variety of shapes, from spheres to rods to three-dimensional structures formed by rod sections interconnected through branching points. The temperature- and time-dependence of the chemical potentials for the monomer species in solution are the most relevant parameters involved in the growth mechanism.

Suitable post-synthesis surface modification of lead-chalcogenide quantum dots (QDs) is crucial to enable their integration in photovoltaic devices. We have developed a solution-phase ligand exchange strategy that exploits arenethiolate anions to replace the pristine oleate ligands on PbS QDs, while preserving the long-term colloidal stability of QDs and allowing their solution-based processability into photoconductive thin-films. Complete QD surface modification is demonstrated by IR spectroscopy analysis, whereas UV-Vis-NIR Absorption Spectroscopy provides quantitative evaluation of stoichiometry and thermodynamic stability of the resulting system. Arenethiolate ligands permit to reduce the inter-particle distance in PbS QD solids, leading to a drastic improvement of the photoinduced charge transport properties. Therefore, smooth dense-packed thin-films of arenethiolate-capped PbS QDs obtained via a single solution-processing step are integrated in heterojunction solar cells: such devices generate remarkable photocurrent densities (14 mA cm(-2)) and overall efficiencies (1.85%), which are outstanding for a single PbS QD layer. Solution-phase surface modification of QDs thus represents an effective intermediate step towards low-cost processing for all-inorganic and hybrid organic/inorganic QD-based photovoltaics. (c) 2013 Elsevier B.V. All rights reserved.

In this study we evaluated an efficient microwave-solvothermal method to synthesize effective visible-light photocatalists based on the use of anatase TiO2 nanorods. The nanocrystals were obtained by hydrolysis of titanium tetraisopropoxide (TTIP) in the presence of benzyl alcohol at 210 °C. The method was effective and produced TiO2 nanocrystals in the anatase phase with a rapid kinetics of crystallization. A significant size control was obtained tuning the TTIP to oleic acid molar ratio. High volumetric yield and reduced energy costs were achieved. All synthesized TiO2 nanocrystals showed a high photoactivity in comparison with commercial P25 titania, as they could degrade faster and completely Rhodamine B dye in solution under visible-light irradiation. The nanocrystals were characterized in detail by X-ray diffraction, low- and high-resolution transmission electron microscopy, microRaman and FT-IR spectroscopy. A distorted anatase structure due to oxygen vacancies was identified as being at the origin of the introduction of new energy levels into the anatase band gap, which probably promoted the visible-light photoactivity.

Il saggio ripercorre le vicende del IV Congresso Internazionale di Filosofia del 1911, che vide l'emergere dell'estetica crociana e la fine della cultura di matrice positivista e illuminista cui il Malaguzzi Valeri si riferiva; questo portò anche alla rottura tra i protagonisti dell'ambiente scientifico positivista con i cultori dell'idealismo. Il tutto nell'assenza sia fisica che intellettuale degli storici d'arte, di alcuni protagonisti dell'epoca quali Corrado Ricci, Igino Benvenuto Supino, Alfonso Rubbiani .

In the realm of semiconductor nanomaterials, a crystal lattice heavily doped with cation/anion vacancies or ionized atomic impurities is considered to be a general prerequisite to accommodating excess free carriers that can support localized surface plasmon resonance (LSPR). Here, we demonstrate a surfactant-assisted nonaqueous route to anisotropic copper sulfide nanocrystals, selectively trapped in the covellite phase, which can exhibit intense, size-tunable LSPR at near-infrared wavelengths despite their stoichiometric, undoped structure. Experimental extinction spectra are satisfactorily reproduced by theoretical calculations performed by the discrete dipole approximation method within the framework of the Drude-Sommerfeld model. The LSPR response of the nanocrystals and its geometry dependence are interpreted as arising from the inherent metallic-like character of covellite, allowed by a significant density of lattice-constitutional valence-band free holes. As a consequence of the unique electronic properties of the nanocrystals and of their monodispersity, coherent excitation of symmetric radial breathing modes is observed for the first time in transient absorption experiments at LSPR wavelengths.

A simple synthesis was applied and tested for the preparation of boron-doped titanium dioxide [TiO2(B)] nanocrystals using titanium tetraisopropoxide (TTIP) together with boric acid (H3BO3) and benzyl alcohol as reaction solvent. Changes in the TTIP/H3BO3 molar ratio allowed a scalable synthetic protocol with a significant B-dopant control. In particular, this approach does not need surfactants or a final calcination step. X-ray diffractometry (XRD), low- and high-resolution transmission electron microscopy (TEM and HRTEM), and micro Raman spectroscopy revealed that the TiO2 nanocrystals produced have diameters up to about 10 nm and are mainly of the anatase phase but that a brookite phase was progressively formed with increased dopant level. The amount of boron was measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES), and the presence of boron inside the crystals was determined by 11B cross-polarized magic-angle spinning nuclear magnetic resonance (11B CP-MAS NMR) spectroscopy. X-ray photoelectron spectroscopy (XPS) revealed the presence of boron on the nanocrystal surfaces, confirming the trend in the dopant concentration already observed with ICP-AES elemental analysis. Microphotoluminescence studies indicated the formation of three different typical luminescent defect states in correlation with the amount of added boron in the titania. UV/Vis absorption spectra showed a boron-dependent redshift of the absorption edge.

We realize nanofibers of regioregular poly(3-hexylthiophene) (P3HT) by solvent-resistant nanolithography and use them as the active medium in organic field effect transistors. This process favors a remarkable improvement of the device performances, since we exploit the nanofluidic flow in perfluoropolyether capillaries and the slow solvent evaporation rate in the mold cavities to induce the reorganization of the P3HT chains and obtain a charge carrier mobility 60 times higher than in the corresponding homogenous films. The precise control of the structure cross-section (sub-100 nm) and of the spatial arrangement on the transistor electrodes is very promising for the development of one-dimensional (1D) nanostructures of conjugated materials with high field-effect mobility, applicable to miniaturized optoelectronic devices.

A three-dimensional (3D) ordered superlattice of colloidal iron oxide nanocrystals obtained by magnetic-field-assisted self-assembly has been studied by grazing incidence small-angle X-ray scattering (GISAXS). A new model to simulate and interpret GISAXS patterns is presented, which returns the structural and morphological details of 3D nanocrystal-built supercrystals. The model is applied to a sample with a suitable surface morphology, allowing the observation of “volume diffraction” even at extremely low grazing incidence angle. In this particular case, the average fcc-like stacking of the nanocrystals (building blocks), their spherical shape, and statistical information on their size distribution and positions within the superlattice have been safely deduced. The proposed model is expected to be amendable for the analysis of more complex structures and applicable to a large variety of nanocrystal-based assemblies.

The structural characterization of ZnS epilayers grown on (100) GaAs by H 2 transport vapour-phase epitaxy is reported. High-resolution X-ray diffraction and ion channelling Rutherford backscattering spectrometric measurements were used to evaluate the overall crystalline perfection of the epilayers and the distortion and reciprocal orientation of the ZnS and GaAs lattices and to measure the epilayer built-in lattice strain. High crystalline quality can be achieved at the surface of relatively thick (above ca. 1 μm) ZnS layers, although a dense distribution of extended defects was observed close to the ZnS/GaAs interface. It turns out that the ZnS unit cell is orthorombically distorted, although its deviation from a purely tetragonal distortion is very small. Systematic measurements of the ZnS lattice strain were performed on the epilayers and the results were compared with the thermal strain value obtained by temperature-dependent X-ray diffraction measurements. The data indicate that the ZnS built-in lattice strain can be entirely ascribed to a thickness-dependent thermal strain contribution, the initial lattice misfit at the growth temperature being almost totally relaxed even for relatively thin epilayers. Finally, no appreciable strain was found for epilayer thicknesses above about 3 μm.