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2.
IEEE Trans Image Process ; 30: 1332-1341, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33315566

RESUMO

The recovery of a real signal from its auto-correlation is a wide-spread problem in computational imaging, and it is equivalent to retrieve the phase linked to a given Fourier modulus. Image-deconvolution, on the other hand, is a funda- mental aspect to take into account when we aim at increasing the resolution of blurred signals. These problems are addressed separately in a large number of experimental situations, ranging from adaptive astronomy to optical microscopy. Here, instead, we tackle both at the same time, performing auto-correlation inversion while deconvolving the current object estimation. To this end, we propose a method based on I -divergence optimization, turning our formalism into an iterative scheme inspired by Bayesian-based approaches. We demonstrate the method by recovering sharp signals from blurred auto-correlations, regardless of whether the blurring acts in auto-correlation, object, or Fourier domain.

3.
J Biophotonics ; : e202000396, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33295053

RESUMO

We present a microscope on chip for automated imaging of Drosophila embryos by light sheet fluorescence microscopy. This integrated device, constituted by both optical and microfluidic components, allows the automatic acquisition of a 3D stack of images for specimens diluted in a liquid suspension. The device has been fully optimized to address the challenges related to the specimens under investigation. Indeed, the thickness and the high ellipticity of Drosophila embryos can degrade the image quality. In this regard, optical and fluidic optimization has been carried out to implement dual-sided illumination and automatic sample orientation. In addition, we highlight the dual color investigation capabilities of this device, by processing two sample populations encoding different fluorescent proteins. This work was made possible by the versatility of the used fabrication technique, femtosecond laser micromachining, which allows straightforward fabrication of both optical and fluidic components in glass substrates.

4.
Phys Chem Chem Phys ; 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33175935

RESUMO

In recent years there has been growing interest in sp-carbon chains as possible novel nanostructures. An example of sp-carbon chains is the so-called polyyne, characterized by the alternation of single and triple bonds that can be synthesized via pulsed laser ablation in liquid (PLAL) of a graphite target. In this work, by using different solvents in the PLAL process, e.g. water, acetonitrile, methanol, ethanol, and isopropanol, we systematically investigated the role of the solvent in polyyne synthesis and stability, and discussed the possible formation mechanisms. The presence of methyl- and cyano-groups in the solutions influences the termination of polyynes, allowing the detection, of hydrogen-capped polyynes up to H-C22-H, methyl-capped polyynes up to H-C18-CH3 and cyanopolyynes up to H-C12-CN. The assignment of each species was performed via UV-vis spectroscopy and supported by density functional theory simulations of vibronic spectra. In addition, surface-enhanced Raman spectroscopy allowed to highlight the differences in the shape and positions of the characteristic Raman bands of the size-selected polyynes with different terminations (hydrogen, methyl and cyano groups). The stability in time of each polyyne was investigated by evaluating the chromatographic peak area, and the effect of size, terminations and solvents on polyyne stability was individuated.

5.
Pediatr Dermatol ; 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33170517

RESUMO

Vascular findings have rarely been described in the setting of lichen sclerosus. Enlarged vessels within the atrophic plaques have been observed on the free margins of the labia minora and clitoral hood. The enlarged vessels completely remit upon treatment of lichen sclerosus with an ultra-potent corticosteroid ointment in the acute phase. During maintenance therapy with calcineurin inhibitors, there was no recurrence of the enlarged vessels.

6.
Stat Methods Med Res ; : 962280220973697, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33243087

RESUMO

Multi-arm multi-stage clinical trials in which more than two drugs are simultaneously investigated provide gains over separate single- or two-arm trials. In this paper we propose a generic Bayesian adaptive decision-theoretic design for multi-arm multi-stage clinical trials with K (K≥2) arms. The basic idea is that after each stage a decision about continuation of the trial and accrual of patients for an additional stage is made on the basis of the expected reduction in loss. For this purpose, we define a loss function that incorporates the patient accrual costs as well as costs associated with an incorrect decision at the end of the trial. An attractive feature of our loss function is that its estimation is computationally undemanding, also when K > 2. We evaluate the frequentist operating characteristics for settings with a binary outcome and multiple experimental arms. We consider both the situation with and without a control arm. In a simulation study, we show that our design increases the probability of making a correct decision at the end of the trial as compared to nonadaptive designs and adaptive two-stage designs.

8.
Artigo em Inglês | MEDLINE | ID: mdl-33070566

RESUMO

BACKGROUND: There are still few dermatological studies on morphea. We evaluated the epidemiological and clinical features and management of pediatric morphea, reporting dermatologists experience. METHODS: A multicentre retrospective observational study was carried out on the epidemiological and clinical features and management of the disease between 01/01/2009 and 01/10/2014 in 10 Italian Dermatological Units. RESULTS: We collected the data of 69 children affected by: circumscribed morphea (39.1%); linear morphea of trunk and limbs (14.5%); en coupe de sabre morphea (ECDS) (14.5%); progressive facial hemiatrophy (8.7%); generalized form (18.8%); mixed morphea (4.4%). The mean age at onset was 6.86±3.21 years, mainly between 2 and 8 years, but is statistically significantly lower for ECDS (4.5±3.03). Localizations were: head/neck (30.4%), limbs (26.1%), trunk (14.5%), 2 or more sites (29%), most often the trunk plus limbs. Extracutaneous manifestations were observed in 26.1% patients. 10 patients presented a second autoimmune disorder. Treatments were topical in 26.1% cases and systemic (alone or associated with topical treatments) in 68.1%. CONCLUSIONS: There was a lack of uniformity in the management of patients and an increasing awareness of dermatologists on the use of systemic therapies, in particular of methotrexate, which is no longer exclusive to rheumatologists. Methotrexate causes stabilization and improvement of the clinical signs, but topical creams are still considered adjuvant or maintenance therapies during/after the use of systemic drugs.

9.
Biomed Opt Express ; 11(8): 4397-4407, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32923051

RESUMO

Single-cell analysis techniques are fundamental to study the heterogeneity of cellular populations, which is the basis to understand several biomedical mechanisms. Light-sheet fluorescence microscopy is a powerful technique for obtaining high-resolution imaging of individual cells, but the complexity of the setup and the sample mounting procedures limit its overall throughput. In our work, we present an optofluidic microscope-on-chip with integrated microlenses for light-sheet shaping and with a fluidic microchannel that allows the automatic and continuous delivery of samples of a few tens of microns in size. The device is used to perform dual-color fluorescence analysis and 3D reconstruction of xenograft-derived mouse breast cancer cells.

10.
Beilstein J Nanotechnol ; 11: 1026-1035, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32733777

RESUMO

We propose the use of gold nanoparticles grown on the surface of nanoporous TiO2 films as surface-enhanced Raman scattering (SERS) sensors for the detection of 17ß-estradiol. Gold deposition on top of a TiO2 surface leads to the formation of nanoparticles the plasmonic properties of which fulfil the requirements of a SERS sensor. The morphological and optical properties of the surface were investigated. Specifically, we demonstrate that the TiO2 background pressure during pulsed laser deposition and the annealing conditions offer control over the formation of Au nanoparticles with different sizes, shapes and distributions, yielding a versatile sensor. We have exploited the surface for the detection of 17ß-estradiol, an emerging contaminant in environmental waters. We have found a limit of detection of 1 nM with a sensitivity allowing for a dynamic range of five orders of magnitude (up to 100 µM).

13.
Sci Rep ; 10(1): 12771, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32728161

RESUMO

Optical Projection Tomography (OPT) is a powerful three-dimensional imaging technique used for the observation of millimeter-scaled biological samples, compatible with bright-field and fluorescence contrast. OPT is affected by spatially variant artifacts caused by the fact that light diffraction is not taken into account by the straight-light propagation models used for reconstruction. These artifacts hinder high-resolution imaging with OPT. In this work we show that, by using a multiview imaging approach, a 3D reconstruction of the bright-field contrast can be obtained without the diffraction artifacts typical of OPT, drastically reducing the amount of acquired data, compared to previously reported approaches. The method, purely based on bright-field contrast of the unstained sample, provides a comprehensive picture of the sample anatomy, as demonstrated in vivo on Arabidopsis thaliana and zebrafish embryos. Furthermore, this bright-field reconstruction can be implemented on practically any multi-view light-sheet fluorescence microscope without complex hardware modifications or calibrations, complementing the fluorescence information with tissue anatomy.

18.
JMIR Mhealth Uhealth ; 8(6): e16165, 2020 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-32357123

RESUMO

BACKGROUND: Childhood obesity prevention is a public health priority in industrialized countries. The Reggio Emilia Local Health Authority has implemented a program involving primary and secondary prevention as well as the care of obese children. There are many health-promoting mobile apps, but few are targeted to children and very few are sponsored by public health agencies. OBJECTIVE: The goal of the research was to describe the process and tools adopted to cocreate a mobile app sponsored by the Reggio Emilia Local Health Authority to be installed in parents' phones aimed at promoting child health and preventing obesity. METHODS: After stakeholder mapping, a consulting committee including relevant actors, stakeholders, and users was formed. Key persons for childhood obesity prevention were interviewed, focus groups with parents and pediatricians were conducted, and community reporting storytelling was collected. The results of these activities were presented to the consulting committee in order to define the functionalities and contents of the mobile app. RESULTS: Three key trends emerged from community reporting: being active, playing, and being outdoors; time for oneself, family, and friends; and the pressures of life and work and not having time to be active and socialize. In focus groups, interviews, and labs, mothers showed a positive attitude toward using an app to manage their children's weight, while pediatricians expressed concerns that the app could increase their workload. When these findings were explored by the consulting committee, four key themes were extracted: strong relationships with peers, family members, and the community; access to safe outdoor spaces; children's need for age-appropriate independence; and professional support should be nonjudgmental and stigma-free. It should be a dialogue that promotes family autonomy. The app functions related to these needs include the following: (1) newsletter with anticipatory guidance, recipes, and vaccination and well-child visit reminders; (2) regional map indicating where physical activity can be done; (3) information on how to manage emergencies (eg, falls, burns, fever); (4) module for reinforcing the counseling intervention conducted by pediatricians for overweight children; and (5) a function to build a balanced daily diet. CONCLUSIONS: The pilot study we conducted showed that cocreation in health promotion is feasible, with the consulting committee being the key co-governance and cocreation tool. The involvement of stakeholders in this committee made it possible to expand the number of persons and institutions actively contributing to the project.

20.
Nano Lett ; 20(7): 4872-4881, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32364743

RESUMO

Here we demonstrate an unconventional fabrication of highly transparent supercapacitors and electrodes using random networks of nanostructured metallic glass nanotroughs for their integrations as wirelessly rechargeable and invisible, skin heat patches. Transparent supercapacitors with fine conductive patterns were printed using an electrohydrodynamic jet-printing. Also, transparent and stretchable electrodes, for wireless antennas, heaters and interconnects, were formed using random network based on nanostructured CuZr nanotroughs and Ag nanowires with superb optoelectronic properties (sheet resistance of 3.0 Ω/sq at transmittance of 91.1%). Their full integrations, as an invisible heat patch on skin, enabled the wireless recharge of supercapacitors and the functions of heaters for thermal therapy of skin tissue. The demonstration of this transparent thermotherapy patch to control the blood perfusion level and hydration rate of skin suggests a promising strategy toward next-generation wearable electronics.

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