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1.
Chempluschem ; : e202400195, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38666666

RESUMEN

Silicon (Si) and silicon/graphite (Si/Gr) composite anodes are promising candidates due to their high theoretical capacity, low operating potential and natural abundance for high energy density Li-ion batteries. Green electrode production, eliminating organic volatile solvents require advancement of aqueous electrodes. Engineering the binder plays a critical role for improving waterborne electrodes. Lithium substituted polyacrylic acid LiPAA has been demonstrated as a promising binder for Si/Gr anodes and for Ni-rich cathodes in different cell configurations. LiPAA is utilized to minimize the volume expansion during cycling for Si/Gr anodes. LiPAA is formed in situ during cathode slurry preparation to regulate the pH and dimmish the Li loss. Using advanced characterization techniques, we investigated the slurries, electrodes, and active material reaction with LiPAA and its effect to the cycling performance. Our results indicate that the performance of high Si containing anode is limited by the amount of Si in the electrode. The failure mechanism with respect to high Si content was studied thoroughly. Aqueous processed cathodes with LiPAA binder in combination with Si anodes outperformed NMP based cathodes. Hence, LiPAA was successfully utilized as an active binder for both a high Si containing anode and for a Ni rich cathode.

2.
J Pers Med ; 13(8)2023 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-37623483

RESUMEN

Since its introduction in the early 2000s, robotic surgery has represented a significative innovation within a minimally invasive surgery approach. A variety of robotic platforms have been made available throughout the years, and the outcomes related to those platforms have been described in the literature for many types of surgeries. Medtronic's HugoTM RAS system is one of the newest robotic generations launched, but because of its recent placing on the field, comprehensive clinical data are still lacking. The aim of the present state of the art is to address the current literature concerning the use of the HugoTM RAS robot in order to report its feasibility, safety and clinical applications in different surgical branches. Two reviewers independently conducted a search on the "PubMed" electronic database, using the keywords "Hugo" and "Hugo RAS". After the initial screening of 35 results, a total of 15 articles concerning the Hugo RAS system were selected for the review, including both oncological and benign surgery. Patients' demographic and baseline data were compared including, when available, docking system times, complications and oncological outcomes in the fields of urologic, gynecologic and general surgery. With reference to urological procedures, a total of 156 robot-assisted radical prostatectomies, 10 robot-assisted partial nephrectomies, and 5 robot-assisted adrenalectomies were performed, involving a total of 171 patients. The surgical branch in which the Hugo system found its major application was urology, which was followed by gynecology and general surgery. The Hugo RAS system by Medtronic represents an innovative and safe surgical platform, with excellent perspective for the future and different clinical applications in many surgical branches. More studies are needed to validate the safety and results from this new robotic platform.

3.
Sci Rep ; 13(1): 9039, 2023 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-37270634

RESUMEN

The presence in nature of species showing drastic differences in lifespan and cancer incidence has recently increased the interest of the scientific community. In particular, the adaptations and the genomic features underlying the evolution of cancer-resistant and long-lived organisms have recently focused on transposable elements (TEs). In this study, we compared the content and dynamics of TE activity in the genomes of four rodent and six bat species exhibiting different lifespans and cancer susceptibility. Mouse, rat, and guinea pig genomes (short-lived and cancer-prone organisms) were compared with that of naked mole rat (Heterocephalus glaber) which is a cancer-resistant organism and the rodent with the longest lifespan. The long-lived bats of the genera Myotis, Rhinolophus, Pteropus and Rousettus were instead compared with Molossus molossus, which is one of the organisms with the shortest lifespan among the order Chiroptera. Despite previous hypotheses stating a substantial tolerance of TEs in bats, we found that long-lived bats and the naked mole rat share a marked decrease of non-LTR retrotransposons (LINEs and SINEs) accumulation in recent evolutionary times.


Asunto(s)
Quirópteros , Neoplasias , Animales , Cobayas , Ratones , Quirópteros/genética , Retroelementos/genética , Incidencia , Envejecimiento , Ratas Topo/genética , Neoplasias/epidemiología , Neoplasias/genética , Neoplasias/veterinaria
4.
Small ; 19(42): e2302868, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37345577

RESUMEN

Here it is described nanogels (NG) based on a chitosan matrix, which are covalently stabilized by a bisamide derivative of Mn-t-CDTA (t-CDTA = trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid). the Mn(II) complex acts both as a contrast medium and as a cross-linking agent. These nanogels are proposed as an alternative to the less stable paramagnetic nanogels obtained by electrostatic interactions between the polymeric matrix and paramagnetic Gd(III) chelates. The present novel nanogels show: i) relaxivity values seven times higher than that of typical monohydrated Mn(II) chelates at the clinical fields, thanks to the combination of a restricted mobility of the complex with a fast exchange of the metal-bound water molecule; ii) high stability of the formulation over time at pH 5 and under physiological conditions, thus excluding metal leaking or particles aggregation; iii) good extravasation and accumulation, with a maximum contrast achieved at 24 h post-injection in mice bearing subcutaneous breast cancer tumor; iv) high T1 contrast (1 T) in the tumor 24 h post-injection. These improved properties pave the way for the use of these paramagnetic nanogels as promising magnetic resonance imaging (MRI) probes for in vitro and in vivo preclinical applications.


Asunto(s)
Imagen por Resonancia Magnética , Neoplasias , Ratones , Animales , Nanogeles , Imagen por Resonancia Magnética/métodos , Quelantes/química , Medios de Contraste/química
5.
World J Pediatr Congenit Heart Surg ; 14(2): 175-179, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36866595

RESUMEN

There has been a paradigm shift in the management of patients with congenital heart disease with a move away from conventional surgical treatment in favor of a percutaneous catheter-based approach across the spectrum of valvular heart diseases. The Sapien S3 valve implantation in the pulmonary position has been previously reported using a conventional transcatheter approach in patients with pulmonary insufficiency due to an enlarged right ventricular outflow tract. In this report, we present 2 unique cases of intraoperative hybrid implantation of Sapien S3 valves in patients with complex pulmonic and tricuspid valvular disease.


Asunto(s)
Enfermedades de las Válvulas Cardíacas , Implantación de Prótesis de Válvulas Cardíacas , Prótesis Valvulares Cardíacas , Insuficiencia de la Válvula Pulmonar , Válvula Pulmonar , Humanos , Cateterismo Cardíaco/métodos , Catéteres , Enfermedades de las Válvulas Cardíacas/diagnóstico por imagen , Enfermedades de las Válvulas Cardíacas/cirugía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Diseño de Prótesis , Válvula Pulmonar/cirugía , Insuficiencia de la Válvula Pulmonar/cirugía , Resultado del Tratamiento , Masculino , Femenino , Adolescente , Adulto
6.
World J Pediatr Congenit Heart Surg ; 14(3): 384-386, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36972503

RESUMEN

The arterial switch operation with single coronary artery variance is an independent risk factor for increased operative mortality. There are reports of technical modifications, such as the double-barreled sinus pouch configuration, to improve geometric reimplantation of the single coronary into the neoaortic sinus. We describe the novel application of this technique for transferring a single coronary artery with a separate nodal artery emanating from the opposite sinus during an arterial switch operation.


Asunto(s)
Operación de Switch Arterial , Anomalías de los Vasos Coronarios , Transposición de los Grandes Vasos , Humanos , Operación de Switch Arterial/métodos , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/cirugía , Transposición de los Grandes Vasos/diagnóstico por imagen , Transposición de los Grandes Vasos/cirugía , Corazón , Anomalías de los Vasos Coronarios/diagnóstico por imagen , Anomalías de los Vasos Coronarios/cirugía , Estudios Retrospectivos
7.
Sensors (Basel) ; 22(24)2022 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-36560066

RESUMEN

Frequency-modulated continuous wave (FMCW) radars are currently being investigated for remote vital signs monitoring (measure of respiration and heart rates) as an innovative wireless solution for healthcare and ambient assisted living. However, static reflectors (furniture, objects, stationary body parts, etc.) within the range or range angular bin where the subject is present contribute in the Doppler signal to a direct current (DC) offset. The latter is added to the person's information, containing also a useful DC component, causing signal distortion and hence reducing the accuracy in measuring the vital sign parameters. Removing the sole contribution of the unwanted DC offset is fundamental to perform proper phase demodulation, so that accurate vital signs monitoring can be achieved. In this work, we analyzed different DC offset calibration methods to determine which one achieves the highest accuracy in measuring the physiological parameters as the transmitting frequency varies. More precisely, by using two FMCW radars, operating below 10 GHz and at millimeter wave (mmWave), we applied four DC offset calibration methods to the baseband radar signals originated by the cardiopulmonary activities. We experimentally determined the accuracy of the methods by measuring the respiration and the heart rates of different subjects in an office setting. It was found that the linear demodulation outperforms the other methods if operating below 10 GHz while the geometric fitting provides the best results at mmWave.


Asunto(s)
Radar , Procesamiento de Señales Asistido por Computador , Humanos , Monitoreo Fisiológico/métodos , Signos Vitales , Respiración , Frecuencia Cardíaca/fisiología , Algoritmos
8.
Sensors (Basel) ; 22(24)2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36560268

RESUMEN

Unmanned ground vehicles (UGVs) find extensive use in various applications, including that within industrial environments. Efforts have been made to develop cheap, portable, and light-ranging/positioning systems to accurately locate their absolute/relative position and to automatically avoid potential obstacles and/or collisions with other drones. To this aim, a promising solution is the use of ultrasonic systems, which can be set up on UGVs and can potentially output a precise reconstruction of the drone's surroundings. In this framework, a so-called frequency-modulated continuous wave (FMCW) scheme is widely employed as a distance estimator. However, this technique suffers from low repeatability and accuracy at ranges of less than 50 mm when used in combination with low-resource hardware and commercial narrowband transducers, which is a distance range of the utmost importance to avoid potential collisions and/or imaging UGV surroundings. We hereby propose a modified FMCW-based scheme using an ad hoc time-shift of the reference signal. This was shown to improve performance at ranges below 50 mm while leaving the signal unaltered at greater distances. The capabilities of the modified FMCW were evaluated numerically and experimentally. A dramatic enhancement in performance was found for the proposed FMCW with respect to its standard counterpart, which is very close to that of the correlation approach. This work paves the way for the future use of FMCWs in applications requiring high precision.

9.
J Card Surg ; 37(12): 5649-5652, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36183397

RESUMEN

Systemic right ventricular failure after physiologic repair for dextro-transposition of the great arteries can be managed with durable mechanical circulatory support; however, the right ventricular morphology, such as intervening papillary muscles, presents challenges to inflow cannula positioning. Papillary muscle repositioning is an innovative technique to circumvent obstructive anatomy.


Asunto(s)
Insuficiencia Cardíaca , Transposición de los Grandes Vasos , Humanos , Transposición de los Grandes Vasos/cirugía , Músculos Papilares/cirugía , Planta de la Mostaza , Insuficiencia Cardíaca/cirugía , Arterias
10.
Inorg Chem ; 61(33): 13199-13209, 2022 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-35944034

RESUMEN

The GdAAZTA (AAZTA = 6-amino-6-methylperhydro-1,4-diazepinetetraacetic acid) complex represents a platform of great interest for the design of innovative MRI probes due to its remarkable magnetic properties, thermodynamic stability, kinetic inertness, and high chemical versatility. Here, we detail the synthesis and characterization of new derivatives functionalized with four amino acids with different molecular weights and charges: l-serine, l-cysteine, l-lysine, and l-glutamic acid. The main reason for conjugating these moieties to the ligand AAZTA is the in-depth study of the chemical properties in aqueous solution of model compounds that mimic complex structures based on polypeptide fragments used in molecular imaging applications. The analysis of the 1H NMR spectra of the corresponding Eu(III)-complexes indicates the presence of a single isomeric species in solution, and measurements of the luminescence lifetimes show that functionalization with amino acid residues maintains the hydration state of the parent complex unaltered (q = 2). The relaxometric properties of the Gd(III) chelates were analyzed by multinuclear and multifrequency NMR techniques to evaluate the molecular parameters that determine their performance as MRI probes. The relaxivity values of all of the novel chelates are higher than that of GdAAZTA over the entire range of applied magnetic fields because of the slower rotational dynamics. Data obtained in reconstituted human serum indicate the occurrence of weak interactions with the proteins, which result in larger relaxivity values at the typical imaging fields. Finally, all of the new complexes are characterized by excellent chemical stability in biological matrices over time, by the absence of transmetallation processes, or the formation of ternary complexes with oxyanions of biological relevance. In particular, the kinetic stability of the new complexes, measured by monitoring the release of Gd3+ in the presence of a large excess of Zn2+, is ca. two orders of magnitude higher than that of the clinical MRI contrast agent GdDTPA.


Asunto(s)
Aminoácidos , Gadolinio , Quelantes/química , Medios de Contraste/química , Gadolinio/química , Humanos , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética
11.
Front Pediatr ; 10: 900142, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35874587

RESUMEN

Transposition of great arteries (d-TGA) is often associated with various coronary artery (CA) patterns. These anomalous patterns can cause variable clinical symptoms of coronary ischemia including sudden death. CA pattern is one of the major determinants of outcome in TGA postoperatively. An advanced cardiac imaging and a multidisciplinary care approach are essential for a favorable outcome. Here, we describe a novel CA origin pattern in a neonate with d-TGA, who developed myocardial ischemia and required a coronary unroofing procedure for a full recovery.

12.
J Am Heart Assoc ; 11(14): e026517, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35861815

RESUMEN

Background Until recently, a large right ventricle outflow tract interfered with the feasibility of standard transcatheter pulmonary valve replacement (PVR). We are describing our experience using a hybrid approach for PVR using a left anterior thoracotomy approach to allow for plication of the main pulmonary artery followed by a transcatheter PVR using a Sapien S3 valve. Methods and Results This is a single-center, retrospective review of patients who were evaluated to be appropriate for a hybrid PVR approach. The patients' demographics, procedure details, and follow-up data were collected. Between May 2018 and April 2021, a total of 11 patients presented for hybrid transcatheter PVR. The median age and weight were 24 years (interquartile range, 19-43 years) and 81.8 kg (interquartile range, 69-91 kg), respectively. Nine out of 11 patients received a transcatheter PVR after main pulmonary artery plication. There were no procedurally related deaths. One major complication was encountered in which the valve was malpositioned requiring successful surgical PVR. Minor complications included acute kidney injury (n=1) and a broken rib (n=1). The median length of stay was 4 days (interquartile range, 2-4 days), with median follow-up of 7 months (interquartile range, 3-18 months). A well-functioning pulmonary valve was observed in all patients at the last follow-up. Conclusions A hybrid approach using left anterior thoracotomy with pulmonary artery plication followed by transcatheter Sapien S3 PVR provides a less-invasive option for patients with an enlarged right ventricular outflow tract. Preliminary results demonstrated this to be a safe option with good short-term outcomes.


Asunto(s)
Implantación de Prótesis de Válvulas Cardíacas , Prótesis Valvulares Cardíacas , Insuficiencia de la Válvula Pulmonar , Válvula Pulmonar , Tetralogía de Fallot , Cateterismo Cardíaco/efectos adversos , Prótesis Valvulares Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/métodos , Ventrículos Cardíacos , Humanos , Arteria Pulmonar/diagnóstico por imagen , Arteria Pulmonar/cirugía , Válvula Pulmonar/diagnóstico por imagen , Válvula Pulmonar/cirugía , Estudios Retrospectivos , Tetralogía de Fallot/cirugía , Toracotomía/efectos adversos , Resultado del Tratamiento
13.
J Imaging ; 8(6)2022 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-35735949

RESUMEN

The potential of any multi-analytical and non-invasive approach to the study of cultural heritage, both for conservation and scientific investigation purposes, is gaining increasing interest, and it was tested in this paper, focusing on the panel painting Madonna della Tenda (Musei Reali, Turin), identified as a 16th-century copy of the painting by Raffaello Sanzio. As a part of a broader diagnostic campaign carried out at the Centro Conservazione e Restauro, La Venaria Reale in Turin, Italy, the potential of the combination of X-ray radiography, pulse-compression thermography, macro X-ray fluorescence, and IR reflectography was tested to investigate the wooden support and all the preparatory phases for the realization of the painting. The results of the optical microscopy and SEM/EDS analyses on a multi-layered micro-sample were used for a precise comparison, integration, and/or confirmation of what was suggested by the non-invasive techniques. Particularly, the radiographic and thermographic techniques allowed for an in-depth study of a hole, interestingly present on the panel's back surface, detecting the trajectory of the wood grain and confirming the presence of an old wood knot, as well as of a tau-shaped element-potentially a cracked and unfilled area of the wooden support-near the hollow. The combination of radiography, macro X-ray fluorescence, Near Infrared (NIR), and Short Wave Infrared (SWIR) reflectography allowed for an inspection of the ground layer, imprimitura, engravings, and underdrawing, not only revealing interesting technical-executive aspects of the artwork realization, but also highlighting the advantages of an integrated reading of data obtained from the different analytical techniques.

14.
Ultrasonics ; 125: 106781, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35671568

RESUMEN

The concept of employing air volumes trapped inside polymer shells to make a lens for ultrasound focusing in water is investigated. The proposed lenses use evenly-spaced concentric rings, each having an air-filled polymer shell construction, defining concentric water-filled channels. Numerical simulations and experiments have shown that a plane wave can be focused, and that the amplification can be boosted by Fabry-Pérot resonances within the water channels with an appropriate choice of the lens thickness. The effect of the polymer shell thickness and the depth of the channels is discussed, as these factors can affect the geometry and hence the frequency of operation. The result was a lens with a Full Width at Half Maximum value of 0.65 of a wavelength at the focus. Results obtained on a metal-based counterpart are also shown for comparison. An advantage of this polymeric design is that it is easily constructed via additive manufacturing. This study shows that trapped-air lenses made of polymer are suitable for ultrasound focusing in water near 500 kHz.

15.
Inorg Chem ; 61(13): 5380-5387, 2022 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-35316037

RESUMEN

Nanogels (NGs) obtained by electrostatic interactions between chitosan and hyaluronic acid and comprising paramagnetic Gd chelates are gaining increasing attention for their potential application in magnetic resonance bioimaging. Herein, the macrocyclic complexes [Gd(DOTP)]5-, lacking metal-bound water molecules (q = 0), were confined or used as a cross-linker in this type of NG. Unlike the typical behavior of Gd complexes with q = 0, a remarkable relaxivity value of 78.0 mM-1 s-1 was measured at 20 MHz and 298 K, nearly 20 times greater than that found for the free complex. A careful analysis of the relaxation data emphasizes the fundamental role of second sphere water molecules with strong and long-lived hydrogen bonding interactions with the complex. Finally, PEGylated derivatives of nanoparticles were used for the first in vivo magnetic resonance imaging study of this type of NG, revealing a fast renal excretion of paramagnetic complexes after their release from the NGs.


Asunto(s)
Quelantes , Gadolinio , Medios de Contraste , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Nanogeles , Oxazoles , Pirimidinonas
16.
Perfusion ; 37(4): 334-339, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-33706597

RESUMEN

In patients with pediatric acute respiratory distress syndrome (PARDS) and hemodynamic compromise who need venoarterial (VA) extracorporeal life support (ECLS), we have adopted a strategy to promote early VA-to-venovenous (VV) conversion since 2018. A single-center retrospective review was performed of all 22 patients who underwent ECLS for PARDS from 2008 to 2019. Variables were analyzed to determine factors affecting initial cannulation mode and in-hospital mortality. Outcomes were compared between before and after 2018. Of the 22 patients, 9 patients underwent initial VA-support. Small patient size and severe cardiopulmonary compromise prior to ECLS favored initial VA- over VV-support. Lactate level and vasoactive inotrope score at 24 hours post-ECLS initiation predicted in-hospital mortality. After 2018, all five patients with initial VA-support were converted to VV-support at 4.4 ± 1.3 days post-ECLS initiation without complications. In-hospital mortality decreased after 2018 (3/9) compared with before (10/13) (p = 0.041) despite longer ECLS run time (723.4 ± 384.2 vs 286.5 ± 235.1 hours, p = 0.003). The number of ECLS-related complications per ECLS 1000 run hours decreased after 2018 (7.2 ± 4.2 vs 46.9 ± 66.5, p = 0.063). Our strategy to promote early VA-to-VV conversion may be worth further evaluation in larger cohort studies.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Síndrome de Dificultad Respiratoria , Cateterismo , Niño , Hemodinámica , Humanos , Síndrome de Dificultad Respiratoria/terapia , Estudios Retrospectivos
17.
J Acoust Soc Am ; 150(1): 74, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34340517

RESUMEN

Metamaterials exhibiting Fabry-Pérot resonances are shown to achieve ultrasonic imaging of a sub-wavelength aperture in water immersion across a broad bandwidth. Holey-structured metamaterials of different thickness were additively manufactured using a tungsten substrate and selective laser melting, tungsten being chosen so as to create a significant acoustic impedance mismatch with water. Both broadband metamaterial behavior and sub-wavelength imaging in water are demonstrated experimentally and validated with finite element simulations over the 200-300 kHz range.

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