The Surfaces of the Ceratonia siliqua L. (Carob) Leaflet: Insights from Physics and Chemistry.

The production of superhydrophobic coatings inspired by the surface of plant leaves is a challenging goal. Such coatings hold a bright technological future in niche markets of the aeronautical, space, naval, building, automobile, and biomedical sectors. This work is focused on the adaxial (top) and abaxial (bottom) surfaces of the leaflet of the Ceratonia silique L. (carob), a high-commercial-value Mediterranean tree cultivated in many regions of the world. The adaxial and abaxial surfaces feature hydrophobic and superhydrophobic behaviors, respectively. Their chemical composition is very simple: monopalmitin ester and palmitic acid are protuberant in the epicuticular and intracuticular wax layers of the adaxial surface, respectively, whereas 1-octacosanol dominates in the abaxial wax layers. In both surfaces, epicuticular wax is organized along a randomly oriented and intricate network of nanometer-thick and micrometer-long plates, whose density and degree of interconnection are significantly higher in the abaxial surface. The measured tilting angles for the abaxial surface (12-70°) reveal unusual variable density and water adhesion of the nanostructured plate-based texture. Optical measurements demonstrate that light reflectance/absorbance of the glaucous abaxial surface is significantly higher/lower than that of the nonglaucous adaxial surface. In both surfaces, diffuse reflectance is dominant, and the absorbance is weakly dependent on the light incidence angle. We show that the highly dense nanostructured platelike texture of the epicuticular abaxial layer of the C. siliqua leaflet works as a sophisticated light and water management system: it reflects solar radiation diffusely to lower the surface temperature, and it has superhydrophobic character to keep the surface dry. Such attributes enable efficient gas exchange (photosynthesis and respiration), transpiration, and evaporation. To mimic for the first time the abaxial surface, a templation approach was adopted using poly(dimethylsiloxane) (PDMS)/poly(methylphenylsiloxane) (PMPS) positive/negative replicas and a soft polymer/siloxane negative replica produced by the sol-gel process. Because high topographical variations of the biotemplate and wax adhesion to the biohybrid film affected the replication quality, the reproduction of the wax texture via the synthesis of 1-octacosanol-grafted siloxane-based hybrid materials is proposed as a suitable route to duplicate the abaxial surface with high fidelity. The natural chemical/physical strategy adopted by the C. siliqua leaflet to face the harsh Mediterranean climate is a powerful source of bioinspiration for the development of diffuse reflecting and superhydrophobic material systems with foreseen applications as dual-functional antiglare and water-repelling coatings.

In vivo chronic nicotine exposure differentially and reversibly affects upregulation and stoichiometry of α4ß2 nicotinic receptors in cortex and thalamus.

Studies with heterologous expression systems have shown that the α4ß2 nicotinic acetylcholine receptor (nAChR) subtype can exist in two stoichiometries (with two [(α4)2(ß2)3] or three [(α4)3(ß2)2] copies of the α subunit in the receptor pentamer) which have different pharmacological and functional properties and are differently regulated by chronic nicotine treatment. However, the effects of nicotine treatment in vivo on native α4ß2 nAChR stoichiometry are not well known. We investigated in C57BL/6 mice the in vivo effect of 14-day chronic nicotine treatment and subsequent withdrawal, on the subunit expression and ß2/α4 subunit ratio of (3)H-epibatidine labeled α4ß2*-nAChR in total homogenates of cortex and thalamus. We found that in basal conditions the ratio of the ß2/α4 subunit in the cortex and thalamus is different indicating a higher proportion in receptors with (α4)2(ß2)3 subunit stoichiometry in the thalamus. For cortex exposure to chronic nicotine elicited an increase in receptor density measured by (3)H-epibatidine binding, an increase in the α4 and ß2 protein levels, and an increase in ß2/α4 subunit ratio, that indicates an increased proportion of receptors with the (α4)2(ß2)3 stoichiometry. For thalamus we did not find a significant increase in receptor density, α4 and ß2 protein levels, or changes in ß2/α4 subunit ratio. All the changes elicited by chronic nicotine in cortex were transient and returned to basal levels with an average half-life of 2.8 days following nicotine withdrawal. These data suggest that chronic nicotine exposure in vivo favors increased assembly of α4ß2 nAChR containing three ß2 subunits. A greater change in stoichiometry was observed for cortex (which has relatively low basal expression of (α4)2(ß2)3 nAChR) than in thalamus (which has a relatively high basal expression of (α4)2(ß2)3 nAChR).

Evaluation of native plant flower characteristics for conservation biological control of Prays oleae.

Several studies have shown that manipulating flowering weeds within an agroecosystem can have an important role in pest control by natural enemies, by providing them nectar and pollen, which are significant sources of nutrition for adults. The aim of this study was to assess if the olive moth, Prays oleae (Bernard, 1788) (Lepidoptera: Praydidae), and five of its main natural enemies, the parasitoid species Chelonus elaeaphilus Silvestri (Hymenoptera: Braconidae), Apanteles xanthostigma (Haliday) (Hymenoptera: Braconidae), Ageniaspis fuscicollis (Dalman) (Hymenoptera: Encyrtidae) and Elasmus flabellatus (Fonscolombe) (Hymenoptera: Eulophidae), as well as the predator Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae), can theoretically access the nectar from 21 flowering weeds that naturally occur in olive groves. Thus, the architecture of the flowers as well as the mouthpart structure and/or the head and thorax width of the pest and its enemies were analyzed. The results suggested that all beneficial insects were able to reach nectar of the plant species from Apiaceae family, i.e. Conopodium majus (Gouan) Loret, Daucus carota L. and Foeniculum vulgare Mill., as well as Asparagus acutifolius L., Echium plantagineum L., Capsella bursa-pastoris (L.) Medik., Raphanus raphanistrum L., Lonicera hispanica Boiss. et Reut., Silene gallica L., Spergula arvensis L., Hypericum perforatum L., Calamintha baetica Boiss. et Reut, Malva neglecta Wallr. and Linaria saxatilis (L.) Chaz. P. oleae was not able to access nectar from five plant species, namely: Andryala integrifolia L., Chondrilla juncea L., Dittrichia viscosa (L.) Greuter, Sonchus asper (L.) Hill and Lavandula stoechas L.

Implementing constrained multi-time approach with bootstrap analysis in ME-2: An application to PM2.5 data from Florence (Italy).

Advanced receptor models have been recently developed and tested in order to improve the resolution of apportionment problems reducing rotational ambiguity of results and aiming at identifying a larger number of sources. In particular, multi-time model is a factor analysis method able to compute source profiles and contributions using aerosol compositional data with different time resolutions. Unlike traditional factor analysis, each measured value can be inserted into multi-time model with its original time schedule, thus all temporal information can be effectively used in the modelling process. In this work, multi-time model was expanded in order to impose constraints on modelled factors aiming at improving the source identification. Moreover, as far as we know for the first time, a suitable bootstrap technique was implemented in the multi-time scheme to estimate the uncertainty of the final constrained solutions. These implemented approaches were tested on a PM2.5 (particulate matter with aerodynamic diameter <2.5 µm) dataset composed of 24-h samples collected during one year and hourly data sampled in parallel for two shorter periods in Florence (Italy). The daily samples were chemically characterised for elements, ions and carbonaceous components while elemental concentrations only were available for high-time resolved samples. The application of the advanced model revealed the major contribution from traffic (accounting for 37% of PM2.5 as annual average) and allowed an accurate characterisation of involved emission processes. In particular, exhaust and non-exhaust emissions were identified. The constraints imposed in the continuation run led to a better description of the factor associated to nitrates and also of biomass burning profile and the bootstrap results gave useful information to assess the reliability of source apportionment solutions. Finally, the comparison with the results computed by ME-2 base model applied to daily and hourly compositional data separately demonstrated the advantages provided by the multi-time approach.

Flexibility of the axial central pattern generator network for locomotion in the salamander.

In tetrapods, limb and axial movements are coordinated during locomotion. It is well established that inter- and intralimb coordination show considerable variations during ongoing locomotion. Much less is known about the flexibility of the axial musculoskeletal system during locomotion and the neural mechanisms involved. Here we examined this issue in the salamander Pleurodeles waltlii, which is capable of locomotion in both aquatic and terrestrial environments. Kinematics of the trunk and electromyograms from the mid-trunk epaxial myotomes were recorded during four locomotor behaviors in freely moving animals. A similar approach was used during rhythmic struggling movements since this would give some insight into the flexibility of the axial motor system. Our results show that each of the forms of locomotion and the struggling behavior is characterized by a distinct combination of mid-trunk motor patterns and cycle durations. Using in vitro electrophysiological recordings in isolated spinal cords, we observed that the spinal networks activated with bath-applied N-methyl-d-aspartate could generate these axial motor patterns. In these isolated spinal cord preparations, the limb motor nerve activities were coordinated with each mid-trunk motor pattern. Furthermore, isolated mid-trunk spinal cords and hemicords could generate the mid-trunk motor patterns. This indicates that each side of the cord comprises a network able to generate coordinated axial motor activity. The roles of descending and sensory inputs in the behavior-related changes in axial motor coordination are discussed.

Observation of surface states with algebraic localization.

We introduce and experimentally demonstrate a class of surface bound states with algebraic decay in a one-dimensional tight-binding lattice. Such states have an energy embedded in the spectrum of scattered states and are structurally stable against perturbations of lattice parameters. Experimental demonstration of surface states with algebraic localization is presented in an array of evanescently coupled optical waveguides with tailored coupling rates.

Photonic realization of the quantum Rabi model.

We realize a photonic analog simulator of the quantum Rabi model, based on light transport in femtosecond-laser-written waveguide superlattices, which provides an experimentally accessible test bed to explore the physics of light-matter interaction in the deep strong coupling regime. Our optical setting enables us to visualize dynamical regimes not yet accessible in cavity or circuit quantum electrodynamics, such as the bouncing of photon number wave packets in parity chains of Hilbert space.

Performance measurements for the PET/CT Discovery-600 using NEMA NU 2-2007 standards.

PURPOSE: The aim of this study was to assess the performance measurements of the new PET/CT system Discovery-600 (D-600, GEMS, Milwaukee, WI). METHODS: Performance measures were obtained with the National Electrical Manufacturers Association (NEMA) NU 2-2007 procedures. RESULTS: The transverse (axial) spatial resolution FWHMs were 4.9 (5.6) mm and 5.6 (6.4) mm at 1 and 10 cm off axis, respectively. The sensitivity (average at 0 and 10 cm) was 9.6 cps/kBq. The scatter fraction was 36.6% (low energy threshold: 425 keV). The NEC peak rate (k=1) was 75.2 kcps at 12.9 kBq/cc. The hot contrasts for 10, 13, 17, and 22 mm spheres were 41%, 51%, 62%, and 73% and the cold contrasts for 28 and 37 mm spheres were 68% and 72%. CONCLUSIONS: The Discovery-600 has good performance for the NEMA NU 2-2007 parameters, particularly in improved sensitivity compared to the scanners of the same Discovery family, D-ST and D-STE.

Performance of a SPECT collimator-detector response reconstruction algorithm: phantom studies and validation in inflammation clinical studies.

AIM: To evaluate evolution for bone (EfB), one of the recent corrective collimator detector response (CDR) image reconstruction packages, resolution recovery and iterative reconstruction protocols were compared to the standard Filtered Back Projection (FBP) protocol and the possibility of time reduced acquisition (15 instead of 30 seconds/projection) was evaluated. METHODS: Tomographic spatial resolution, contrast, noise and signal-to-noise ratio (SNR) were analyzed in phantom studies. Patient studies were conducted on sixteen [99mTc]HMPAO labeled leukocyte patients with suspected local inflammation, submitted to SPECT/CT and conventional leukocyte scintigraphy. Target background ratio (TBR) and boundary of each lesion were calculated. Images were also analyzed by visual inspection by two blinded expert physicians. RESULTS: a) Phantom: resolution in phantom improves with the use of EfB mainly due to iterative reconstruction methods vs FBP. EfB shows a reduction in noise. No differences were found in contrast data, while SNR changes were mainly due to changes in noise. Time reduction, while increasing image noise, does not modify resolution; nevertheless, half-time EfB noise is the same as full-time FBP noise. b) PATIENTS: lesion boundary is better defined in patient studies using iterative reconstruction vs FBP; no changes were observed for CDR vs iterative OSEM, or for full-time vs half-time acquisition. TBR is comparable in iterative and FBP protocols, while it is improved by EfB. At visual inspection, a higher score is always associated with EfB. CONCLUSION: Resolution, noise, SNR and TBR improve when applying the resolution recovery. EfB permits reduction of acquisition time without compromising image quality.

Clinical validation of a specially sized class II compression knee-sock for the prevention of recurrent ulcers in patients with chronic venous stasis (CEAP 5).

AIM: Patients cured of venous ulcers (VU) often suffer recurrences if they do not wear elastic compression hosiery. Unfortunately, only half of them can benefit of this treatment, because their leg proportions have changed, obliging them to order to measure products which are harder to find, and expensive. This study was designed to validate a class II elastic knee-sock (GGG-Ral standards) manufactured on the basis of the ankle and calf circumferences of recently cured patients. METHODS: In all, 177 consecutive patients were given a sock that fitted properly, to be worn for 30 days. Numerical and analogue symptom scales and a questionnaire on clinical improvement have been used to evaluate treatment benefits. RESULTS: Symptom improvements reached respectively 68% and 65% and clinical improvements 96% of the patients. Compliance was 91.6%. CONCLUSIONS: Specially-sized elastic hose for patients cured of VU would serve to treat the large numbers who cannot use routine-production sizes, with improvements in compliance and clinical symptoms.

Cardiac mesoangioblasts are committed, self-renewable progenitors, associated with small vessels of juvenile mouse ventricle.

Different cardiac stem/progenitor cells have been recently identified in the post-natal heart. We describe here the identification, clonal expansion and characterization of self-renewing progenitors that differ from those previously described for high spontaneous cardiac differentiation. Unique coexpression of endothelial and pericyte markers identify these cells as cardiac mesoangioblasts and allow prospective isolation and clonal expansion from the juvenile mouse ventricle. Cardiac mesoangioblasts express many cardiac transcription factors and spontaneously differentiate into beating cardiomyocytes that assemble mature sarcomeres and express typical cardiac ion channels. Cells similarly isolated from the atrium do not spontaneously differentiate. When injected into the ventricle after coronary artery ligation, cardiac mesoangioblasts efficiently generate new myocardium in the peripheral area of the necrotic zone, as they do when grafted in the embryonic chick heart. These data identify cardiac mesoangioblasts as committed progenitors, downstream of earlier stem/progenitor cells and suitable for the cell therapy of a subset of juvenile cardiac diseases.

Grayscale calibration and quality assurance of diagnostic monitors in a PACS system.

PURPOSE: The aim of this study was to calibrate monitors used in soft-copy review of diagnostic images in a pictures archiving and communication system (PACS) and to assess critical quality assurance (QA) parameters through appropriate checks. MATERIALS AND METHODS: Barco [cathode ray tube (CRT) and liquid crystal display (LCD)] and EIZO (LCD) monitors were evaluated. Calibration and QA controls were carried out during acceptance tests on the systems and every 6 months according to the Task Group 18 (TG18) report by the American Association of Physicists in Medicine (AAPM). The parameters in question include: maximum luminance, contrast ratio, luminance response, spatial resolution and angular response. A subjective evaluation of image quality was also conducted by a number of radiologists. RESULTS: Barco medical monitors' results were well within tolerances, with significant parameters persisting over time. EIZO nonmedical monitors showed rapid performance deterioration below the minimum requirements. Calibration had to be repeated only in a few cases. Radiologists' evaluations showed that monitor quality is equal to or even better than that of conventional films. CONCLUSIONS: Medical monitors turned out to be fully adequate to the task. Periodic QA tests are, however, absolutely necessary to ensure constant quality levels.

Effect of a sustained silver-releasing dressing on ulcers with delayed healing: the CONTOP study.

OBJECTIVE: To compare the effect of the sustained silver-releasing foam dressing Contreet Foam (ColoplastA/S) with local best practice (LBP) on delayed healing ulcers using a real-life setting. METHOD: A total of 619 patients with ulcers of varying aetiologies were treated for four weeks with either the silver foam dressing or LBP. RESULTS: Wound area was reduced by 50% with the silver foam and 34% with LBP Less slough and maceration, a faster reduction in exudate level and more positive wound progress was achieved with the silver foam. In addition, exudate handling, ease of use, odour and pain improved. Less time was spent on dressing changes, and mean wear time was longer for the silver foam (3.1 days) than for LBP (2.1 days). All differences were statistically significant (p < 0.05). The silver foam dressing outperformed all of the other dressing categories including moist wound healing products and other silver dressings. CONCLUSION: This large-scale comparative real-life study shows that the silver foam dressing supports faster healing of delayed healing wounds.

Accuracy of stereotactic localisation with magnetic resonance compared to CT scan: experimental findings.

BACKGROUND: Stereotactic localisation of proper targets can be obtained with Magnetic Resonance imaging (MRI), pending correction of the well-known inaccuracy of MRI in reproducing exact geometrical dimension. The aim of the experimental work was to determine the real extent of the MRI distortion and to correct it. METHODS: PVC phantoms and fixed human brains were used as target simulators: stereotactic targeting was obtained with CT and MRI: the results were compared and, finally, the real stereotactic values were measured on a commercial stereotactic device. To optimise MRI targeting it was necessary to abate the "chemical-shift", to modify the head-coil receiver (tuning the "off-resonance" frequencies) and to correct the targeting directly on the images (especially for the Y axis values); careful quality control and environmental tests were also necessary to maintain good performances along the time. RESULTS: 172 measurements were carried out using both CT, plain X-ray and MRI on PVC phantom. The values obtained from CT were considered as reference. Significant geometrical accuracy was found with CT targeting, except for the Z co-ordinate, due to the slice thickness. Mean value differences between the targets on MRI and their real geometric position are about 1 mm on X and Z axises and about 2 mm on Y axis. Similar results were obtained on fixed brains, where absolute values of X and Y co-ordinates of the simulators were measured using a millimetre grid placed over the brain slice. INTERPRETATION: Experimental findings concerning stereotactic targeting with MRI suggest accuracy adequate for clinical practice, even when extreme geometrical precision is required, such as in radiosurgery or functional stereotaxy. Careful quality control and intensive experimental setting of the MRI device are mandatory to obtain satisfactory results.

[The evaluation of the physical characteristics of a volumetric computer tomograph]. / Valutazione delle caratteristiche fisiche di un tomografo computerizzato volumetrico.

Spiral or volumetric computed tomography (CT) is a new scanning technique which allows the scanning of body regions with a continuously rotating system based on the slip ring technology; the patient is also moved continuously, synchronously with data acquisition. The physical characteristics of spiral CT image acquisition were compared with those of conventional CT images. The modulation transfer function (MTF) has the same values for medium-resolution filters, but lower values for spiral CT for high-resolution and frequency-enhancement filters. The slice sensitivity profile (SSP) describes the longitudinal image resolution for multiplanar reconstructions and was measured in terms of FWHM of the SSP curve. We obtained, for 10-mm slice thickness, a FWHM = 10.4 mm (conventional CT), versus 10.7 mm (Spiral CT), while, for 5-mm slice thickness, the corresponding values were 5.2 mm (conventional CT) and 5.5 mm (spiral CT). Noise was evaluated simply by measuring the standard deviation of the CT numbers, in a region of interest, of a uniform image and with the power spectrum or Wiener spectrum of the same image. To assess overall image quality and yield, the noise equivalent quanta (NEQ) value was also calculated. The values were a little lower for the spiral technique, particularly with high-resolution and enhancement or convolution filters. Dosimetric evaluation of the computed tomography dose index (CTDI) and of the multiple scan average dose (MSAD) was done using an acquisition protocol for average lung dose, in an anthropomorphic phantom and with TL dosimeters. The MSAD was 6.17 +/- 0.20 cGy for conventional CT and 5.98 +/- 0.23 cGy for Spiral CT, while lung dose was 3.25 +/- 0.12 cGy and 3.01 +/- 0.16 cGy, respectively.

[Late radiation-induced injuries: breast carcinoma in post-actinic ulceration of the thoracic-breast region with infected osteoradionecrosis. A case report]. / Danno tardivo da radiazioni: carcinoma della mammella su ulcera post-attinica della regione toraco-mammaria con osteoradionecrosi contaminata. Descrizione di un caso.

Severe skin reactions are commonly observed after breast irradiation. Chronic ulcerations, soft tissue damage and osteonecrosis are well-known though relatively rare long-term radiation-induced injuries. The ever-present possibility of recurrence or persistence of the primary malignant neoplasm within the irradiated tissue must be always suspected and adequately established by multiple biopsies before planning an eventual resective and or reconstructive strategy. In the present report a neoplastic recurrence arised from an extensive radiation-induced ulceration along the parasternal area with chest wall osteonecrosis complicated by infection in a 42 y.o. woman, who had received postoperative roentgen therapy a long time before for breast carcinoma and thyroid cancer, is described. Radiation-induced injuries and therapeutical options are discussed in relation to the site of the lesion and to the complexity of the single case. In conclusion, when recurrent malignancy is present, although the long-term prognosis may be poor, the quality of life of many patients undoubtedly may be improved by a multidisciplinary approach involving oncologysts, as well as general, thoracic and plastic surgeons.

[Digital storage phosphor radiography. Doses and image quality]. / Radiografia digitale con fosfori. Dose e qualità delle immagini.

Digital radiography (DR) based on storage phosphor technology is progressively replacing conventional screen-film system radiographic techniques (CR). However, many questions about image quality and dose reduction are still open. Thus, since DR spatial resolution is always lower than that of high quality screen-film images and image noise is conversely higher, for general radiography examinations especially, the signal-to-noise ratio is always lower with DR than with CR at the same dose level. However, the wide dynamic range, the linear response of storage phosphor detectors and the automatic read-out control of the digital system, enable lower DR X-ray imaging efficiency to be overcome, producing a nearly perfect readout of the image data every time an exposure is made. Moreover, post-processing can make the detection of abnormalities easier. This is why in many ROC clinical accuracy studies DR performed equally or better than CR. Good quality DR images, similar to conventional ones at the same dose levels, are therefore achievable in chest, abdomen, bone and soft-tissues examinations. Dose evaluation protocols are strongly needed in DR since overexposures due to technical mistakes may be overlooked; moreover, doses can be adjusted to the peculiar diagnostic need. The S values shown on any hard-copy image can be used to this purpose, even though it must be pointed out that they do not express the actual mean dose to the detector.

[The detectability of osteoarticular lesions of the extremities on the television monitor]. / Riconoscibilità delle lesioni osteoarticolari delle estremità al monitor televisivo.

The diagnostic accuracy of the light-box reading of conventional (film screen) radiographs of the extremities was compared with that of the same set of images displayed on a 1 k x 1 k interactive monitor after laser digitization. 389 alterations (23 nondisplaced fractures, 129 soft-tissue calcifications and 237 articular bone erosions), identified by two experienced radiologists on 66 conventional radiographs, were the reference standard. ROC statistical analysis was performed on 1,556 observations expressed by four readers. The overall diagnostic performance of the two display modalities were substantially equivalent: no statistically significant differences resulted on the whole, but two individual readers performed better with conventional images. No overall nor individual statistically significant difference was reobserved for the subset of articular erosions either. Light-box reading of conventional radiographs allowed a higher number of calcifications in the soft-tissues and of proximal (carpal) abnormalities to be detected. Although our results indicate the overall high fidelity of monitor-displayed laser-digitized images, major improvements in the performance of digital diagnostic workstations are still required before adopting monitors for routine radiologic activity.