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1.
Small ; 20(20): e2304716, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38335309

RESUMO

The last decade observed rapid progress in soft electronics. Yet, the ultimate desired goal for many research fields is to fabricate fully integrated soft-matter electronics with sensors, interconnects, and batteries, at the ease of pushing a print button. In this work, an important step is taken toward this by demonstrating an ultra-stretchable thin-film Silver-Gallium (Ag-Ga) battery with an unprecedented combination of areal capacity and mechanical strain tolerance. The Biphasic Gallium-Carbon anode electrode demonstrates a record-breaking areal capacity of 78.7 mAh cm-2, and an exceptional stretchability of 170%, showing clear progress over state-of-the-art. The exceptional theoretical capacity of gallium, along with its natural liquid phase self-healing, and its dendrite-free operation permits excellent electromechanical cycling. All composites of the battery including liquid-metal-based current collectors, and electrodes are sinter-free and digitally printable at room temperature, enabling the use of a wide range of substrates, including heat-sensitive polymer films. Consequently, it is demonstrated for the first time multi-layer, and multi-material digital printing of complex battery-on-the-board stretchable devices that integrate printed sensor, multiple cells of printed battery, highly conductive interconnects, and silicone chips, and demonstrate a tailor-made patch for body-worn electrophysiological monitoring.

2.
Adv Mater ; 34(31): e2203266, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35697348

RESUMO

E-waste is rapidly turning into another man-made disaster. It is proposed that a paradigm shift toward a more sustainable future can be made through soft-matter electronics that are resilient, repairable if damaged, and recyclable (3R), provided that they achieve the same level of maturity as industrial electronics. This includes high-resolution patterning, multilayer implementation, microchip integration, and automated fabrication. Herein, a novel architecture of materials and methods for microchip-integrated condensed soft-matter 3R electronics is demonstrated. The 3R function is enabled by a biphasic liquid metal-based composite, a block copolymer with nonpermanent physical crosslinks, and an electrochemical technique for material recycling. In addition, an autonomous laser-patterning method for scalable circuit patterning with an exceptional resolution of <30 µm in seconds is developed. The phase-shifting property of the BCPs is utilized for vapor-assisted "soldering" circuit repairing and recycling. The process is performed entirely at room temperature, thereby opening the door for a wide range of heat-sensitive and biodegradable polymers for the next generation of green electronics. The implementation and recycling of sophisticated skin-mounted patches with embedded sensors, electrodes, antennas, and microchips that build a digital fingerprint of the human electrophysiological signals is demonstrated by collecting mechanical, electrical, optical, and thermal data from the epidermis.


Assuntos
Dispositivos Eletrônicos Vestíveis , Eletrodos , Eletrônica , Humanos , Metais , Polímeros/química
3.
ACS Appl Mater Interfaces ; 13(12): 14552-14561, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33689286

RESUMO

A bi-phasic ternary Ag-In-Ga ink that demonstrates high electrical conductivity, extreme stretchability, and low electromechanical gauge factor (GF) is introduced. Unlike popular liquid metal alloys such as eutectic gallium-indium (EGaIn), this ink is easily printable and nonsmearing and bonds strongly to a variety of substrates. Using this ink and a simple extrusion printer, the ability to perform direct writing of ultrathin, multi-layer circuits that are highly stretchable (max. strain >600%), have excellent conductivity (7.02 × 105 S m-1), and exhibit only a modest GF (0.9) related to the ratio of percent increase in trace resistance with mechanical strain is demonstrated. The ink is synthesized by mixing optimized quantities of EGaIn, Ag microflakes, and styrene-isoprene block copolymers, which functions as a hyperelastic binder. When compared to the same composite without EGaIn, the Ag-In-Ga ink shows over 1 order of magnitude larger conductivity, up to ∼27× lower GF, and ∼5× greater maximum stretchability. No significant change over the resistance of the ink was observed after 1000 strain cycles. Microscopic analysis shows that mixing EGaIn and Ag microflakes promotes the formation of AgIn2 microparticles, resulting in a cohesive bi-phasic ink. The ink can be sintered at room temperature, making it compatible with many heat-sensitive substrates. Additionally, utilizing a simple commercial extrusion based printer, the ability to perform stencil-free, digital printing of multi-layer stretchable circuits over various substrates, including medical wound-dressing adhesives, is demonstrated for the first time.

4.
An Acad Bras Cienc ; 92(4): e20200519, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33331446

RESUMO

Leiomyomas are the most common benign tumors in women. Many of them are associated with significant morbidity. The present study aimed to analyze histomorphological and histochemical characteristics and immunoexpression of Cripto-1 in oral leiomyomas (OL), uterine leiomyomas (UL), and normal myometrium (NM). Sample was composed of ten OL, 11 UL and 11 NM. Histomorphological characteristics were analyzed at 100 and 400x magnifications with HE staining. The immunoexpression of Cripto-1 was analyzed in five high-power fields. Statistical analysis considered a significant difference when p<0.05. Six OL disclosed moderate/intense inflammatory infiltrate, while ten UL exhibited mild infiltrate (p=0.024). When analyzing all leiomyomas together, 20 exhibited hyalinization, whereas no NM exhibited this alteration (p<0.001). There was no statistical difference in the distribution of mast cells among the lesions. The median Cripto-1 was higher in UL (9.0), followed by OL and NM (4.0). Associations of the Cripto-1 expression between leiomyomas (separately and together) and NM were statistically significant (p<0.001). These results indicate that OL and UL exhibit similar histomorphological and histochemical characteristics, as well as differences to NM. The higher immunoexpression of Cripto-1 in leiomyomas compared to NM suggests that this protein may influence cell proliferation and tissue architecture of oral and uterine leiomyomas.


Assuntos
Leiomioma , Neoplasias Uterinas , Feminino , Humanos , Miométrio
5.
Sensors (Basel) ; 20(23)2020 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-33260466

RESUMO

This article reviews recent advances and existing challenges for the application of wearable bioelectronics for patient monitoring and domiciliary hospitalization. More specifically, we focus on technical challenges and solutions for the implementation of wearable and conformal bioelectronics for long-term patient biomonitoring and discuss their application on the Internet of medical things (IoMT). We first discuss the general architecture of IoMT systems for domiciliary hospitalization and the three layers of the system, including the sensing, communication, and application layers. In regard to the sensing layer, we focus on current trends, recent advances, and challenges in the implementation of stretchable patches. This includes fabrication strategies and solutions for energy storage and energy harvesting, such as printed batteries and supercapacitors. As a case study, we discuss the application of IoMT for domiciliary hospitalization of COVID 19 patients. This can be used as a strategy to reduce the pressure on the healthcare system, as it allows continuous patient monitoring and reduced physical presence in the hospital, and at the same time enables the collection of large data for posterior analysis. Finally, based on the previous works in the field, we recommend a conceptual IoMT design for wearable monitoring of COVID 19 patients.


Assuntos
Teste para COVID-19/instrumentação , COVID-19/diagnóstico , COVID-19/fisiopatologia , Serviços Hospitalares de Assistência Domiciliar , Monitorização Fisiológica/instrumentação , Dispositivos Eletrônicos Vestíveis , Fontes de Energia Elétrica , Desenho de Equipamento , Humanos , Pandemias , SARS-CoV-2 , Tecnologia sem Fio/instrumentação
6.
Cell Tissue Bank ; 19(4): 659-666, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30069709

RESUMO

Tissue Banks have become the main source for bone grafts, due to preference for homologous tissues. Notwithstanding the use of aseptic techniques for procurement of tissues and judicious selection of donors, microorganisms are frequently found in procured bones. Purpose of this study is to evaluate the factors that increase safety of procurement and minimize discard of procured tissues. Microbiological contamination was analyzed in 1271 musculoskeletal tissues removed from 138 multi-organ donors over a period extending from 2006 to 2016. Effects of various risk factors related with contamination were estimated using a logistic regression model. Microbiological contamination rate in the tissues was 17.1%; low pathogenic microorganisms were cultivated in 12.9% of the tissues, while highly pathogenic ones were cultivated in 4.2% of the tissues. Evolution of one single team was monitored during that period, verifying a fall in the general contamination level from 22.5 to 9.2%. Absence of antibiotics increased low pathogenic contamination risk. Every additional day in intensive care unit (ICU) increased the risk of highly pathogenic contamination. Time elapsed between death and the beginning of removal procedures was found to be relevant for both low pathogenic and highly pathogenic microorganisms. Among the studied factors, the following contributed for a significant increase in contamination by microorganisms in removed tissues: lack of use of prophylactic antibiotic therapy in donors, quantity of removed tissues, length of admission in ICU and the time elapsed between aortic clamping and beginning of the removal procedure.


Assuntos
Sistema Musculoesquelético/microbiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Risco , Adulto Jovem
7.
FEBS Lett ; 561(1-3): 137-43, 2004 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-15013765

RESUMO

Glucosylceramides (GlcCer) were extracted from the plant pathogen Colletotrichum gloeosporioides and purified by several chromatographic steps. By using electrospray ionization mass spectrometry and nuclear magnetic resonance, GlcCer from C. gloeosporioides were identified as N-2'-hydroxyoctadecanoyl-1-beta-D-glucopyranosyl-9-methyl-4,8-sphingadienine and N-2'-hydroxyoctadecenoyl-1-beta-D-glucopyranosyl-9-methyl-4,8-sphingadienine. Monoclonal antibodies against these structures were produced and used as tools for the evaluation of the role of GlcCer in the morphological transition of C. gloeosporioides. In the presence of antibodies to GlcCer, the differentiation of conidia into mycelia was blocked. Since GlcCer is present in several plant pathogens, the inhibitory activity of external ligands recognizing these structures may be applicable in other models of fungal infections.


Assuntos
Colletotrichum/química , Colletotrichum/citologia , Glucosilceramidas/isolamento & purificação , Glucosilceramidas/fisiologia , Anticorpos Monoclonais/biossíntese , Cerebrosídeos/imunologia , Cerebrosídeos/isolamento & purificação , Colletotrichum/crescimento & desenvolvimento , Glucosilceramidas/imunologia , Espectroscopia de Ressonância Magnética , Microscopia de Fluorescência , Morfogênese , Micélio/citologia , Espectrometria de Massas por Ionização por Electrospray , Esporos Fúngicos/citologia
8.
Am J Hypertens ; 17(1): 50-3, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14700512

RESUMO

BACKGROUND: Obesity is a risk factor for the incidence of hypertension, but it is still unclear whether this risk can be better estimated by body mass index (BMI) or waist circumference (WC). METHODS: In the baseline evaluation of a population-based cohort, 1089 adults answered a pretested questionnaire and had their baseline blood pressure (BP) and anthropometric measurements assessed according to standardized recommendations. Excluding the individuals with hypertension at baseline, and those deceased or lost during the follow-up, 592 individuals (80.5% of those eligible) were visited again. Obesity was defined as BMI >/=30 kg/m(2) for both genders, and WC >/=102 cm for men and WC >/=88 cm for women. Incident cases of hypertension were characterized by BP >/=140/90 mm Hg or use of BP medication in the follow-up visit. RESULTS: After a mean follow-up of 5.6 +/- 1.1 years, 127 incident cases of hypertension were identified. The hazard ratios (Cox model), adjusted for age and baseline systolic BP (95% CI and P), for BMI higher than 30 kg/m(2) were 1.08 (0.52-2.24, P =.82) in men and 1.74 (0.93-3.26, P =.08) in women. The corresponding figures were 1.78 (0.76-4.09, P =.18) for men with WC >/=102, and 1.72 (1.09-2.73, P =.02) for women with WC >/=88 cm. CONCLUSIONS: We conclude that the risk for hypertension may be better identified by obesity defined by higher WC than higher BMI.


Assuntos
Constituição Corporal , Índice de Massa Corporal , Hipertensão/epidemiologia , Obesidade/complicações , Adulto , Determinação da Pressão Arterial , Feminino , Humanos , Hipertensão/etiologia , Incidência , Masculino , Pessoa de Meia-Idade , Obesidade/diagnóstico , Fatores de Risco
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