Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
1.
Sensors (Basel) ; 24(5)2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38475016

RESUMO

The proliferation of radio frequency (RF) devices in contemporary society, especially in the fields of smart homes, Internet of Things (IoT) gadgets, and smartphones, underscores the urgent need for robust identification methods to strengthen cybersecurity. This paper delves into the realms of RF fingerprint (RFF) based on applying the Jensen-Shannon divergence (JSD) to the statistical distribution of noise in RF signals to identify Bluetooth devices. Thus, through a detailed case study, Bluetooth RF noise taken at 5 Gsps from different devices is explored. A noise model is considered to extract a unique, universal, permanent, permanent, collectable, and robust statistical RFF that identifies each Bluetooth device. Then, the different JSD noise signals provided by Bluetooth devices are contrasted with the statistical RFF of all devices and a membership resolution is declared. The study shows that this way of identifying Bluetooth devices based on RFF allows one to discern between devices of the same make and model, achieving 99.5% identification effectiveness. By leveraging statistical RFFs extracted from noise in RF signals emitted by devices, this research not only contributes to the advancement of the field of implicit device authentication systems based on wireless communication but also provides valuable insights into the practical implementation of RF identification techniques, which could be useful in forensic processes.

2.
ACS Sens ; 9(2): 631-637, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38323985

RESUMO

Wireless communication technologies, particularly radio frequency (RF), have been widely explored for wearable electronics with secure and user-friendly information transmission. By exploiting the operational principle of chemically actuated resonant devices (CARDs) and the electrical response observed in chemiresistive materials, we propose a simple and hands-on alternative to design and manufacture RF tags that function as CARDs for wireless sensing of meat freshness. Specifically, the RF antennas were meticulously designed and fabricated by lithography onto a flexible substrate with conductive tape, and the RF signal was characterized in terms of amplitude and peak resonant frequency. Subsequently, a single-walled carbon nanotube (SWCNT)/MoS2/In2O3 chemiresistive composite was incorporated into the RF tag to convey it as CARDs. The RF signal was then utilized to establish a correlation between the sensor's electrical response and the RF attenuation signal (reflection coefficient) in the presence of volatile amines and seafood (shrimp) samples. The freshness of the seafood samples was systematically assessed throughout the storage time by utilizing the CARDs, thereby underscoring their effective potential for monitoring food quality. Specifically, the developed wireless tags provide cumulative amine exposure data within the food package, demonstrating a gradual decrease in radio frequency signals. This study illustrates the versatility of RF tags integrated with chemiresistors as a promising pathway toward scalable, affordable, and portable wireless chemical sensors.


Assuntos
Qualidade dos Alimentos , Carne , Carne/análise , Aminas
3.
Sensors (Basel) ; 23(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37765872

RESUMO

The development and growth of Wireless Sensor Networks (WSNs) is significantly propelled by advances in Radio Frequency (RF) and Visible Light Communication (VLC) technologies. This paper endeavors to present a comprehensive review of the state-of-the-art in cognitive hybrid RF-VLC systems for WSNs, emphasizing the critical task of seamlessly integrating Cognitive Radio Sensor Networks (CRSNs) and VLC technologies. The central challenge addressed is the intricate landscape of this integration, characterized by notable trade-offs between performance and complexity, which escalate with the addition of more devices and increased data rates. This scenario necessitates the development of advanced cognitive radio strategies, potentially facilitated by Machine Learning (ML) and Deep Learning (DL) approaches, albeit introducing new complexities such as the necessity for pre-training with extensive datasets. The review scrutinizes the fundamental aspects of CRSNs and VLC, spotlighting key areas like Energy Efficient Resource Allocation, Industrial Scenarios, and Energy Harvesting, and explores the synergistic amalgamation of these technologies as a promising pathway for enhanced spectrum utilization and network performance. By delving into the integration of cognitive radio technology with visible light, this study furnishes valuable insights into the potential for innovative applications in wireless communication, presenting a balanced overview of the current advancements and prospective avenues in the field of cognitive hybrid RF/VLC systems.

4.
Sensors (Basel) ; 23(17)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37688001

RESUMO

The expectation for communication systems beyond 5G/6G is to provide high reliability, high throughput, low latency, and high energy efficiency services. The integration between systems based on radio frequency (RF) and visible light communication (VLC) promises the design of hybrid systems capable of addressing and largely satisfying these requirements. Hybrid network design enables complementary cooperation without interference between the two technologies, thereby increasing the overall system data rate, improving load balancing, and reducing non-coverage areas. VLC/RF hybrid networks can offer reliable and efficient communication solutions for Internet of Things (IoT) applications such as smart lighting, location-based services, home automation, smart healthcare, and industrial IoT. Therefore, hybrid VLC/RF networks are key technologies for next-generation communication systems. In this paper, a comprehensive state-of-the-art study of hybrid VLC/RF networks is carried out, divided into four areas. First, indoor scenarios are studied considering lighting requirements, hybrid channel models, load balancing, resource allocation, and hybrid network topologies. Second, the characteristics and implementation of these hybrid networks in outdoor scenarios with adverse conditions are analyzed. Third, we address the main applications of hybrid VLC/RF networks in technological, economic, and socio-environmental domains. Finally, we outline the main challenges and future research lines of hybrid VLC/RF networks.

5.
Arq. gastroenterol ; Arq. gastroenterol;60(2): 201-207, Apr.-June 2023. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1447385

RESUMO

ABSTRACT Background: Anorectal functional pain syndrome, also called chronic proctalgia, represents a neglected clinical entity and often confused with other syndromes such as vulvodynia or acute proctalgia. It is a very often disabling disease with a consequent significant negative impact on the patient's quality of life. Chronic proctalgia, in many patients, is secondary to the paradoxical contraction of the pelvic floor and associated with a dissynergy between the thorax-abdomen and the pelvic floor. To improve symptoms in functional anorectal pain syndromes, various rehabilitation techniques are used with the aim of promoting relaxation of the pelvic floor; however, to improve defecatory dynamics in patients with levator ani syndrome, only biofeedback has shown efficacy in a randomized study. The aim of this work is to evaluate whether a rehabilitation protocol with manometric biofeedback and radiofrequency diathermy (mt100 Fremslife emotion Tecar) reduces pain and paradoxical contraction of the levator ani and improves the quality of life in patients with anorectal pain syndromes. functional. Methods: This was a prospective study on 30 patients (20 women and 10 men) with anorectal functional pain syndrome and paradoxical contraction of the pelvic floor enrolled at the UOC of General, Minimally Invasive, Oncological and Obesity Surgery of the AOU "Luigi Vanvitelli" of Naples, Italy, from September 2021 to May 2022. All patients were evaluated with a coloproctological specialist visit followed by anorectal manometry and evaluation of altered clinical physiatric parameters (Brusciano Score). The protocol consisted of 10 rehabilitation sessions of the pelvic floor once a week and lasting approximately 45 minutes. During the sessions the patients were subjected to diathermy / radiofrequency treatment (10 minutes) with a static resistive electrode on the diaphragm, during which they were required to breathe diaphragmatically and to become aware of the perineal muscles, under the supervision of a physiotherapist; followed by application of diathermy with static capacitive (5 minutes) and resistive (10 minutes) electrode at the lumbar level. This was followed by the use of manometric biofeedback (15 minutes of tonic / phasic exercises) in order to instruct the patient on the reflex mechanism to obtain a voluntary relaxation of the external anal sphincter. The variables evaluated were Pain (VAS 0-10) and the questionnaire on the impact of colorectal and anal pathologies on the quality of life (CRAIQ-7) at the beginning, after 3 months and at the end of the treatment. Results: After 10 weeks, the rehabilitation treatment combined with diathermy and manometric biofeedback proved effective in the short term with a reduction in the scores of the Vas scale and CRAIQ-7 questionnaire and an increase in the percentage of release of the anal muscles on anorectal manometry. Conclusion: The use of radiofrequency diathermy with a system of static electrodes associated with biofeedback represents a valid rehabilitation option for those patients suffering from anorectal functional pain syndrome because it reduces pain and paradoxical contraction of the levator ani and improves quality of life of the patient.


RESUMO Contexto: A síndrome de dor funcional anorretal, também conhecida como proctalgia crônica, representa uma entidade clínica negligenciada e frequentemente confundida com outras síndromes, como vulvodinia ou proctalgia aguda. Trata-se de uma doença frequentemente incapacitante, com um consequente impacto negativo significativo na qualidade de vida do paciente. A proctalgia crônica, em muitos pacientes, é secundária à contração paradoxal do assoalho pélvico e está associada a uma dissinergia entre o tórax-abdômen e o assoalho pélvico. Para melhorar os sintomas em síndromes de dor anorretal funcional, são utilizadas diversas técnicas de reabilitação com o objetivo de promover o relaxamento do assoalho pélvico. No entanto, para melhorar a dinâmica de evacuação em pacientes com síndrome do elevador do ânus, apenas o biofeedback demonstrou eficácia em um estudo randomizado. Objetivo: O objetivo deste trabalho é avaliar se um protocolo de reabilitação com biofeedback manométrico e diatermia por radiofrequência (mt100 Fremslife emotion Tecar) reduz a dor e a contração paradoxal do elevador do ânus e melhora a qualidade de vida em pacientes com síndromes de dor anorretal funcional. Métodos: Realizado estudo prospectivo com 30 pacientes (20 mulheres e 10 homens) com síndrome de dor anorretal funcional e contração paradoxal do assoalho pélvico inscritos na UOC de Cirurgia Geral, Minimamente Invasiva, Oncológica e de Obesidade da AOU "Luigi Vanvitelli" de Nápoles, Itália, de setembro de 2021 a maio de 2022. Todos os pacientes foram avaliados com uma consulta especializada em coloproctologia, seguida de manometria anorretal e avaliação dos parâmetros fisiátricos clínicos alterados (Escore de Brusciano). O protocolo consistiu em 10 sessões de reabilitação do assoalho pélvico, uma vez por semana, com duração aproximada de 45 minutos. Durante as sessões, os pacientes foram submetidos a tratamento de diatermia / radiofrequência (10 minutos) com um eletrodo resistivo estático no diafragma, durante o qual foram solicitados a respirar através do diafragma e a tomar consciência dos músculos perineais, sob a supervisão de um fisioterapeuta; seguido pela aplicação de diatermia com eletrodo capacitivo estático (5 minutos) e resistivo (10 minutos) no nível lombar. Isso foi seguido pelo uso de biofeedback manométrico (15 minutos de exercícios tônicos /fásicos) com o objetivo de instruir o paciente sobre o mecanismo reflexo para obter um relaxamento voluntário do esfíncter anal externo. As variáveis avaliadas foram Dor (EVA 0-10) e o questionário sobre o impacto das patologias colorretais e anais na qualidade de vida (CRAIQ-7) no início, após 3 meses e no final do tratamento. Resultados: Após 10 semanas, o tratamento de reabilitação combinado com diatermia e biofeedback manométrico mostrou-se eficaz a curto prazo, com uma redução nos escores da escala VAS e do questionário CRAIQ-7, e um aumento na porcentagem de relaxamento dos músculos anais na manometria anorretal. Conclusão: O uso de diatermia por radiofrequência com um sistema de eletrodos estáticos associado ao biofeedback representa uma opção de reabilitação válida para pacientes que sofrem com a síndrome de dor anorretal funcional, pois reduz a dor e a contração paradoxal do elevador do ânus, melhorando a qualidade de vida do paciente.

6.
Rev Environ Health ; 38(4): 655-661, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35962646

RESUMO

Since 2016, numerous American and Canadian diplomats and secret (intelligence) agents in Cuba, China, and other places in the world have experienced an abrupt onset of unusual clinical symptoms including, tinnitus, visual problems, vertigo, and cognitive difficulties, after they encountered strange sounds; this has been called "Havana syndrome" (HS). MEDLINE, Scopus, and Ovid databases from 2016 until 24 September 2021 were systematically searched for the related published manuscripts. The following search strategy was implemented: "Havana syndrome" OR "Neurological Symptoms and US Diplomats". The primary search yielded 120 publications. Only five original studies and 18 non-original articles were considered to be relevant. While these studies provided a constellation of signs and symptoms for HS, none provided a good level of evidence. In conclusion, Havana syndrome is a nonspecific neurological illness with an unidentified causative factor(s), an acute phase of auditory-vestibular symptoms and a chronic phase of nonspecific neurobehavioral symptoms. This syndrome should be considered and investigated as a health concern, and not as a political issue.


Assuntos
Doenças do Sistema Nervoso , Canadá , China , Cuba , Estados Unidos , Doenças do Sistema Nervoso/diagnóstico
8.
Inquiry ; 58: 469580211065681, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34904895

RESUMO

Our society has advanced in terms of technology, and health could not be different. Despite the benefits and advantages that such improvements entail, it is unknown what contributions have been added to the hospital environment and whether such technological engineering has managed to generate value and adapt to different factors within such institutions' professional culture to establish relevance to the base of utilitarian nature. The use of tools can be conditioned to the view that the managerial sectors have such instruments. The work aims to identify and understand the perception that health managers have traceability tools such and their view on their efficiency and effectiveness in the hospital environment. The results direct us that the traceability tools have a significant expression in the hospital context, collaborating for efficiency and efficacy. Traceability tools can help the entire health system to be more uniform in service, in accountability, and in inspection processes.


Assuntos
Hospitais , Percepção , Brasil , Humanos
9.
Stereotact Funct Neurosurg ; 99(6): 521-525, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34107470

RESUMO

BACKGROUND: Surgical interventions for spasticity aim to improve motor function and pain in cases that are refractory to medical treatment. Ablation of the cerebellar dentate nucleus (dentatotomy) may be a useful alternative. CASE REPORT: A 55-year-old male patient with spasticity, secondary to a traumatic cervical spinal cord injury with quadriparesis, had bilateral lumbar DREZotomy with an improvement that lasted for 6 years. Ten years after the DREZotomy, a progressive increased spasticity manifested as spastic diplegia (Ashworth 4) and spontaneous muscle painful spasms (Penn 4), as well as spasticity in the upper extremities, predominantly on the right side (Ashworth 3). A right radio frequency dentatotomy was performed with intraoperative electrophysiological monitoring. Spasticity scales were applied at the following times: preoperative and at 1 and 8 months after surgery. During the first month, the patient presented a clear decrease in spasticity ipsilateral to the side of lesioning (Ashworth 1) and of painful spasms in the lower extremities (Penn 1). After 8 months, spasticity ipsilateral to the injury decreased even more to Ashworth (0), but a progressive increase in muscle spasms of lower extremities was observed (Penn 2). CONCLUSION: Stereotactic dentatotomy may be an effective surgical alternative for management of spasticity associated with painful spasms in selected patients.


Assuntos
Espasticidade Muscular , Dor , Núcleos Cerebelares/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/cirurgia
10.
West Indian med. j ; West Indian med. j;69(1): 51-55, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1341870

RESUMO

ABSTRACT Objective: To reveal the effect of 2100 MHz radio frequency (RF) radiation on thyroid tissues of rats in the 10 days (group E1) and 40 days (group G1) exposure groups. Methods: In this study, 30 healthy female Wistar albino rats, weighing 200−256 g each, were used. The animals were randomly divided into four groups (E1, E2, G1 and G2). Groups E2 and G2 served as the control groups. The exposure groups were exposed to 2100 MHz RF radiation emitted by a generator, simulating a 3G-mobile phone for 6 hours/day, 5 consecutive days/week, at the same time of the day (between 9 am and 3 pm), for 10 days (group E1) and 40 days (group G1). Results: Catalase and xanthine oxidase enzyme activities were compared between the groups E1 and E2; it was found that the difference was statistically significant (p < 0.05). Between the groups G1 and G2, the difference was found to be significant with respect to catalase activities. Tissue samples of the early and late groups showed no serious pathological findings in the histopathological examination. Conclusion: We believe that comprehensive, clinical and experimental studies are needed to assess the effect of the RF exposure duration and dosage of exposure on thyroid tissues.


Assuntos
Animais , Feminino , Ratos , Doses de Radiação , Glândula Tireoide/efeitos da radiação , Anormalidades Induzidas por Radiação , Ratos Wistar , Modelos Animais
11.
Femina ; 48(12): 764-768, dez. 31, 2020. ilus
Artigo em Português | LILACS | ID: biblio-1141188

RESUMO

O líquen escleroso vulvar (LEV) é uma doença dermatológica crônica de etiologia incerta, caracterizada por prurido intenso e atrofia progressiva. O corticosteroide tópico de longo prazo é o tratamento de primeira linha para LEV. No entanto, esse tratamento requer a colaboração da paciente, está associado a efeitos colaterais adversos e algumas pacientes não respondem aos corticosteroides. O tratamento com tecnologias térmicas e fototérmicas tem sido estudado como terapia alternativa ou complementar para melhorar os sintomas de LEV e o trofismo cutâneo. A radiofrequência fracionada microablativa é usada em dermatologia para melhorar o trofismo tecidual. Também tem sido usada em pacientes ginecológicas para tratar a atrofia vulvovaginal, estimulando a neocolagênese dérmica e a neoelastogênese. Apresentamos o caso de uma mulher de 39 anos com LEV refratária que foi tratada com aplicações locais de radiofrequência fracionada microablativa. Ela apresentou melhora satisfatória dos sintomas e do trofismo vulvar em longo prazo, sem necessidade do uso de corticosteroides.(AU)


Vulvar lichen sclerosus (VLS) is a chronic dermatological disease of unclear etiology characterized by severe itching and progressive atrophy. Long-term topical corticosteroid is the first-line treatment for VLS. However, this treatment requires patient compliance, is associated with adverse side effects, and some patients do not respond to corticosteroids. Treatment with thermal and photothermal technologies have been studied as alternative or complementary therapies to improve VLS symptoms and skin trophism. Microablative fractional radiofrequency (MFR) is used in dermatology to improve tissue trophism. It has also been used in gynecological patients to treat vulvovaginal atrophy by stimulating dermal neocollagenesis and neoelastinogenesis. We present the case of a 39-year-old woman with refractory VLS who was treated with local applications of microablative fractional radiofrequency. She had satisfactory, long-term, improvement of symptoms and vulvar trophism, and stopped using corticosteroids.(AU)


Assuntos
Humanos , Feminino , Adulto , Terapia por Radiofrequência , Líquen Escleroso Vulvar/radioterapia , Prurido Vulvar/radioterapia , Atrofia/radioterapia , Corticosteroides/uso terapêutico , Líquen Escleroso Vulvar/tratamento farmacológico
12.
Sensors (Basel) ; 20(4)2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32093218

RESUMO

This paper presents the design and validation of a traceability system, based on radio frequency identification (RFID) technology and Internet of Things (IoT) services, intended to address the interconnection and cost-implementation problems typical in traceability systems. The RFID layer integrates temperature sensors into RFID tags, to track and trace food conditions during transportation. The IoT paradigm makes it possible to connect multiple systems to the same platform, addressing interconnection problems between different technology providers. The cost-implementation issues are addressed following the Data as a Service (DaaS) billing scheme, where users pay for the data they consume and not the installed equipment, avoiding the big initial investment that these high-tech solutions commonly require. The developed system is validated in two case scenarios, one carried out in controlled laboratory conditions, monitoring chopped pumpkin. Another case, carried out in a real scenario, monitors oranges sent from Valencia, Spain to Cork, Ireland.

13.
Animal ; 12(3): 634-639, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28820079

RESUMO

The objective of this study was to validate an electronic system for monitoring individual feeding and drinking behaviour and intake developed for young cattle housed in group. A total of 35 Holstein-Gyr crossbred heifers (BW: 180±52 kg; age: 121.5±32.5 days), fitted with an ear tag containing a unique passive transponder, were distributed in three groups of 12, 12 and 11 animals per period and had free access to 12 electronic feed bins and two electronic water bins (Intergado® Ltd). The dimensions of feed and water bins, as well as the sensors position were appropriate for young cattle. The system documented the visit frequency and duration, as well as the feed and water intakes, by recording the animal's identification tag, bin number, initial and final times of visits and the difference of feed/water weight at the start and end of each bin visit. Feed bins were monitored using time-lapse video recording over 4 days and the water bins were monitored over 6 days. For each feed bin, two feeding events were monitored using manual weighings with an external scale immediately before and after the animal's visit and the difference between them was assumed as feed intake (n=24 observations). For the water bins, 60 manual weighings were made. Video and manual weighing data were regressed on the electronic feeding and drinking behaviour and intake data to evaluate the system's precision and accuracy. The system showed high specificity (98.98% and 98.56% for the feed and water bins, respectively) and sensitivity (99.25% and 98.74%, respectively) for identifying an animal's presence or absence. Duration of feed and water bin visits as well as feed and water consumption per visit estimated by the system were highly correlated and precise compared with the observed video and manual weighing data (r 2=0.917, 0.963, 0.973 and 0.986, respectively). It was concluded that Intergado® system is a useful tool for monitoring feeding and drinking behaviour as well as water and feed intakes in young cattle housed in groups.


Assuntos
Bovinos/fisiologia , Comportamento de Ingestão de Líquido , Ingestão de Líquidos , Comportamento Alimentar , Ração Animal , Animais , Peso Corporal , Indústria de Laticínios , Ingestão de Alimentos , Feminino , Dispositivo de Identificação por Radiofrequência , Sensibilidade e Especificidade , Gravação em Vídeo
14.
Einstein (Säo Paulo) ; 16(1): eAO3997, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-891459

RESUMO

ABSTRACT Objective To test performance of SurgiSafe®, a radiofrequency electronic device to detect surgical textiles during operations as compared to manual counting. Methods Surgical sponges with radiofrequency TAGs were placed in the abdominal cavity of a pig submitted to laparotomy, in randomly distributed sites. The TAGs were counted manually and also using SurgiSafe®. Positive and negative predictive values, sensitivity, specificity and time required for counting were analyzed for both methods. Results Through the analysis of 35 surgical cycles, SurgiSafe® immediately identified all sponges, with specificity, sensitivity, positive and negative predictive values of 100%. Although not statistically significant, the manual count had sensitivity of 99.72% and specificity of 99.90%. Conclusion SurgiSafe® proved to be an effective device to identify surgical sponges in vivo, in real time; and its use as an adjuvant to manual counting is very helpful to increase patient's safety.


RESUMO Objetivo Testar o desempenho do SurgiSafe®, dispositivo eletrônico de detecção de têxteis cirúrgicos por radiofrequência no intraoperatório, comparado à contagem manual. Métodos Gazes com etiquetas de radiofrequência (TAGs) foram alocadas na cavidade abdominal de um suíno submetido à laparotomia, em locais distribuídos aleatoriamente. As TAGs foram contadas manualmente e com uso do SurgiSafe®. Valores preditivos positivos e negativos, sensibilidade, especificidade e tempo de contagem foram analisados para ambos os métodos. Resultados Por meio da análise de 35 ciclos cirúrgicos, o SurgiSafe® fez a identificação instantânea de todas as gazes, com especificidade, sensibilidade, valores preditivos negativo e positivo de 100%. Apesar de não apresentar significância estatística, a contagem manual apresentou sensibilidade de 99,72% e especificidade de 99,90%. Conclusão O SurgiSafe® mostrou-se eficaz para contabilização de têxteis cirúrgicos em tempo real in vivo, e seu uso como adjuvante na contagem manual é de grande valor para o aumento de segurança do paciente.


Assuntos
Animais , Ondas de Rádio , Telas Cirúrgicas , Monitorização Intraoperatória/métodos , Corpos Estranhos/diagnóstico , Laparotomia/métodos , Suínos , Valor Preditivo dos Testes , Sensibilidade e Especificidade
15.
Food Sci. Technol (SBCTA, Impr.) ; Food Sci. Technol (SBCTA, Impr.);37(4): 544-551, Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-892223

RESUMO

Abstract Radio frequency heating (RFH) provides higher efficiency and more uniform heating zone compared with conventional method. The aim of present work is to evaluate the effect of RFH (at 90 °C for 5 or 10 min) on the changes in composition (protein oxidation and fat distribution), microstructure, flow characteristic and rehydration property of infant milk powder. The results indicate that the concentration of protein dityrosine was slightly enhanced, more free fat appeared on powder surfaces (> 50% increase), and porosity in powder matrix as tested by SEM was increased after RFH treatment. For powder flowability, raw sample had low cohesiveness (specific energy = 4.39 mJ/g), and RFH provided better flowability and decreased compressibility. Moreover, RFH had some negative impacts on wettability and solubility of powder particles with contact angle increase at least 5% and solubility decrease of 2%~4%, indicating worse rehydration abilities. Guggenheim-Anderson-de Boer (GAB) model was applied to fit moisture vapor sorption isotherms, and longer RFH duration leading to higher c values (about 63% increase at 10 min). In addition, the RFH initiated browning reaction as CIE a* values increased from -1.8 to -1.3.

16.
Rev. ecuat. neurol ; Rev. ecuat. neurol;26(1): 61-66, ene.-abr. 2017.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1099136

RESUMO

Resumen El teléfono celular es un dispositivo muy utilizado por personas de todas las edades y en todas partes del mundo. Entre los estudios realizados respecto a los efectos perjudiciales de las radiaciones en el organismo humano no existe un consenso. Por ello es preciso analizar los referentes teóricos acerca de los efectos deletéreos de las radiaciones sobre el ser humano e identificar un conjunto de acciones que contribuyan a disminuir la exposición a este tipo de radiaciones. El objetivo general es dar la información al usuario sobre la exposición a la radiofrecuencia excesiva por el uso indiscriminado del celular y para advertir sobre los problemas de salud que puede producir y las consecuencias que en un futuro podría desencadenar. Las radiaciones pueden afectar al ser humano de forma negativa, sobre todo por exposición prolongada. Diversos estudios revisados indican que las radiaciones están asociadas a la aparición de alteraciones de la salud y describen que entre los mecanismos fundamentales para producir el daño en el hombre se encuentran los efectos térmicos, no térmicos y atérmicos, pero se requieren ampliar los estudios, con énfasis en los epidemiológicos, para analizar las hipótesis generadas acerca de este particular.


Abstract The cell phone is a device widely used by people of all ages and all over the world. Among the studies regarding the harmful effects of radiation on the human body there is no consensus. It is therefore necessary to analyze the theoretical references about the deleterious effects of radiation on humans and identify a set of actions to help reduce exposure to this radiation. The overall objective is to give information to the user about excessive exposure to radio frequency by the indiscriminate use of cell phone and to warn about the health problems that can occur and the consequences that could trigger in the future. Radiation can affect humans negatively, especially prolonged exposure. Various studies reviewed indicate that radiation is associated with the onset of health disorders and described that fundamental mechanism to produce damage in man are thermal, non-thermal and a thermal effects, but it is required to extend studies, with emphasis on epidemiological, to analyze the generated hypotheses about this particular.

17.
Ann Med Surg (Lond) ; 3(2): 31-3, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25568782

RESUMO

BACKGROUND: Counting the sponges is an important step in surgical procedures. A miscount may impact the patient's health, and it also has legal implications for the surgeon. This is an experimental study evaluating radio-frequency technology used in the perioperative period to identify surgical sponges left in the peritoneal cavity of swine. METHODS: Radio-frequency labeled-disc identification tags were sewn into 40 surgical towels. Twenty labels had the ability to emit radio-frequency waves, and 20 labels were inert to radio-frequency identification. Twenty adult pigs that underwent laparotomy and randomly received two surgical sponges were scanned by a radio-frequency identification antenna. RESULTS: This method presented a positive predictive value of 100% and 100% specificity and sensitivity, as all of the tagged surgical sponges were detected. CONCLUSION: Radio-frequency identification has been proved to be a useful method for the identification of surgical sponges within the abdominal cavities of swine.

18.
J Forensic Dent Sci ; 5(2): 77-84, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24255554

RESUMO

OBJECTIVE: To evaluate the in vitro behavior of a passive Radio Frequency Identification (RFID) microchip implanted in human molars subjected to compression forces to determine its technical and clinical viability. MATERIALS AND METHODS: In vitro experimental study to evaluate the physical behavior of a passive RFID microchip (VeriChip™) implanted in human molars through resin restoration (Filtek P90™ Silorane 3M-ESPE(®)) to determine the clinical and technical possibilities of the implant and the viability to withstand compression forces exerted by the stomatognathic system during mastication. RESULTS: Through the ANOVA test, it was found that the teeth on which a microchip was implanted show great resistance to compressive forces. It was also evident that teeth with microchips implanted in Class V cavities are more resistant than those implanted in Class I cavities. CONCLUSIONS: Although microchip dimensions are big, requiring a sufficiently large cavity, from the biomechanical point of view it is plausible to implant a microchip in a Class V cavity employing restoration material based on resin for forensic purposes of human identification.

19.
Ci. Rural ; 42(8)2012.
Artigo em Português | VETINDEX | ID: vti-707882

RESUMO

This paper presents the tests of a telemetry system (T-SADA) to be adapted to the management of agricultural mechanization using a self-propelled combine harvester to harvest soybeans and rice. The system consists of collecting and sending data of a moving point (a farm machine) to a fixed base (a computer server) and makes the integration of two means of transmission and validation of data (providing fault tolerance). The means of data transmission used were the technology of mobile telephony, GSM / GPRS and radio frequency through the Zigbee. The T-SADA is redundant because it has more than one form of transmission, which ensures the transmission of information even if a media is not able to operate correctly at any given time. Priority is given to the transmission GSM / GPRS and leaving the ZigBee as an alternative means, controlled by an engine fault detection. The results were satisfactory ensuring the transmission of data with fault tolerance and redundantly in remote locations and in different relief.


Este trabalho apresenta os testes de um sistema de telemetria (T-SADA) que foi adaptado ao gerenciamento da mecanização agrícola utilizando uma colhedora automotriz autopropelida na colheita de soja e arroz irrigado. O sistema consiste na coleta e envio de dados de um ponto móvel (a máquina agrícola) para uma base fixa (um computador servidor) e faz a integração de dois meios de transmissão e a validação dos dados (propiciando tolerância a falhas). Os meios de transmissão de dados usados foram a tecnologia da telefonia móvel, GSM/GPRS, e rádio-frequência, através do Zigbee. O T-SADA é redundante, pois possui mais de uma forma de transmissão, o que garante o envio das informações mesmo se um dos meios não tiver condições de operar corretamente num determinado momento. É dada prioridade para a transmissão GSM/GPRS e deixando o ZigBee como meio alternativo, controlado por um mecanismo de detecção de falhas. Os resultados alcançados foram satisfatórios, garantindo a transmissão dos dados com tolerância a falhas e de forma redundante em locais remotos e em diferentes relevos.

20.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1479088

RESUMO

This paper presents the tests of a telemetry system (T-SADA) to be adapted to the management of agricultural mechanization using a self-propelled combine harvester to harvest soybeans and rice. The system consists of collecting and sending data of a moving point (a farm machine) to a fixed base (a computer server) and makes the integration of two means of transmission and validation of data (providing fault tolerance). The means of data transmission used were the technology of mobile telephony, GSM / GPRS and radio frequency through the Zigbee. The T-SADA is redundant because it has more than one form of transmission, which ensures the transmission of information even if a media is not able to operate correctly at any given time. Priority is given to the transmission GSM / GPRS and leaving the ZigBee as an alternative means, controlled by an engine fault detection. The results were satisfactory ensuring the transmission of data with fault tolerance and redundantly in remote locations and in different relief.


Este trabalho apresenta os testes de um sistema de telemetria (T-SADA) que foi adaptado ao gerenciamento da mecanização agrícola utilizando uma colhedora automotriz autopropelida na colheita de soja e arroz irrigado. O sistema consiste na coleta e envio de dados de um ponto móvel (a máquina agrícola) para uma base fixa (um computador servidor) e faz a integração de dois meios de transmissão e a validação dos dados (propiciando tolerância a falhas). Os meios de transmissão de dados usados foram a tecnologia da telefonia móvel, GSM/GPRS, e rádio-frequência, através do Zigbee. O T-SADA é redundante, pois possui mais de uma forma de transmissão, o que garante o envio das informações mesmo se um dos meios não tiver condições de operar corretamente num determinado momento. É dada prioridade para a transmissão GSM/GPRS e deixando o ZigBee como meio alternativo, controlado por um mecanismo de detecção de falhas. Os resultados alcançados foram satisfatórios, garantindo a transmissão dos dados com tolerância a falhas e de forma redundante em locais remotos e em diferentes relevos.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA