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1.
Sensors (Basel) ; 24(7)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38610546

RESUMO

The study of plant electrophysiology offers promising techniques to track plant health and stress in vivo for both agricultural and environmental monitoring applications. Use of superficial electrodes on the plant body to record surface potentials may provide new phenotyping insights. Bacterial nanocellulose (BNC) is a flexible, optically translucent, and water-vapor-permeable material with low manufacturing costs, making it an ideal substrate for non-invasive and non-destructive plant electrodes. This work presents BNC electrodes with screen-printed carbon (graphite) ink-based conductive traces and pads. It investigates the potential of these electrodes for plant surface electrophysiology measurements in comparison to commercially available standard wet gel and needle electrodes. The electrochemically active surface area and impedance of the BNC electrodes varied based on the annealing temperature and time over the ranges of 50 °C to 90 °C and 5 to 60 min, respectively. The water vapor transfer rate and optical transmittance of the BNC substrate were measured to estimate the level of occlusion caused by these surface electrodes on the plant tissue. The total reduction in chlorophyll content under the electrodes was measured after the electrodes were placed on maize leaves for up to 300 h, showing that the BNC caused only a 16% reduction. Maize leaf transpiration was reduced by only 20% under the BNC electrodes after 72 h compared to a 60% reduction under wet gel electrodes in 48 h. On three different model plants, BNC-carbon ink surface electrodes and standard invasive needle electrodes were shown to have a comparable signal quality, with a correlation coefficient of >0.9, when measuring surface biopotentials induced by acute environmental stressors. These are strong indications of the superior performance of the BNC substrate with screen-printed graphite ink as an electrode material for plant surface biopotential recordings.


Assuntos
Grafite , Agricultura , Transporte Biológico , Carbono , Clorofila , Vapor
2.
Sensors (Basel) ; 22(19)2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36236730

RESUMO

This paper presents a system for behavioral, environmental, and physiological monitoring of working dogs using on-body and aerial sensors. The proof of concept study presented here includes two trained dogs performing nine scent detection tasks in an uncontrolled environment encompassing approximately two acres. The dogs were outfitted with a custom designed wearable harness to monitor their heart rate, activity levels and skin temperature. We utilized a commercially available micro-air vehicle to perform aerial sensing by tracking the terrain and movement of the dog in the outdoor space. The dogs were free to explore the space working at maximal speeds to complete a scent-based search-and-retrieval task. Throughout the experiment, the harness data was transferred to a base station via Wi-Fi in real-time. In this work, we also focused on testing the performance of a custom 3D electrode with application specific ergonomic improvements and adaptive filter processing techniques to recover as much electrocardiography data as possible during high intensity motion activity. We were able to recover and use 84% of the collected data where we observed a trend of heart rate generally increasing immediately after successful target localization. For tracking the dogs in the aerial video footage, we applied a state-of-the-art deep learning algorithm designed for online object tracking. Both qualitative and quantitative tracking results are very promising. This study presents an initial effort towards deployment of on-body and aerial sensors to monitor the working dogs and their environments during scent detection and search and rescue tasks in order to ensure their welfare, enable novel dog-machine interfaces, and allow for higher success rate of remote and automated task performance.


Assuntos
Eletrocardiografia , Cães Trabalhadores , Algoritmos , Animais , Cães , Frequência Cardíaca , Monitorização Fisiológica
3.
Sensors (Basel) ; 22(15)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35898084

RESUMO

Agricultural and environmental monitoring programs often require labor-intensive inputs and substantial costs to manually gather data from remote field locations. Recent advances in the Internet of Things enable the construction of wireless sensor systems to automate these remote monitoring efforts. This paper presents the design of a modular system to serve as a research platform for outdoor sensor development and deployment. The advantages of this system include low power consumption (enabling solar charging), the use of commercially available electronic parts for lower-cost and scaled up deployments, and the flexibility to include internal electronics and external sensors, allowing novel applications. In addition to tracking environmental parameters, the modularity of this system brings the capability to measure other non-traditional elements. This capability is demonstrated with two different agri- and aquacultural field applications: tracking moth phenology and monitoring bivalve gaping. Collection of these signals in conjunction with environmental parameters could provide a holistic and context-aware data analysis. Preliminary experiments generated promising results, demonstrating the reliability of the system. Idle power consumption of 27.2 mW and 16.6 mW for the moth- and bivalve-tracking systems, respectively, coupled with 2.5 W solar cells allows for indefinite deployment in remote locations.


Assuntos
Agricultura , Pesquisa Interdisciplinar , Eletrônica , Monitoramento Ambiental/métodos , Reprodutibilidade dos Testes
4.
IEEE Sens J ; 21(7): 9413-9422, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33776594

RESUMO

Amputees are prone to experiencing discomfort when wearing their prosthetic devices. As the amputee population grows this becomes a more prevalent and pressing concern. There is a need for new prosthetic technologies to construct more comfortable and well-fitted liners and sockets. One of the well-recognized impediments to the development of new prosthetic technology is the lack of practical inner socket sensors to monitor the inner socket environment (ISE), or the region between the residual limb and the socket. Here we present a capacitive pressure sensor fabricated through a simple, and scalable sewing process using commercially available conductive yarns and textile materials. This fully-textile sensor provides a soft, flexible, and comfortable sensing system for monitoring the ISE. We provide details of our low-power sensor system capable of high-speed data collection from up to four sensor arrays. Additionally, we demonstrate two custom set-ups to test and validate the textile-based sensors in a simulated prosthetic environment. Finally, we utilize the textile-based sensors to study the ISE of a bilateral transtibial amputee. Results indicate that the textile-based sensors provide a promising potential for seamlessly monitoring the ISE.

5.
Sensors (Basel) ; 20(16)2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32796611

RESUMO

Disaster robotics is a growing field that is concerned with the design and development of robots for disaster response and disaster recovery. These robots assist first responders by performing tasks that are impractical or impossible for humans. Unfortunately, current disaster robots usually lack the maneuverability to efficiently traverse these areas, which often necessitate extreme navigational capabilities, such as centimeter-scale clearance. Recent work has shown that it is possible to control the locomotion of insects such as the Madagascar hissing cockroach (Gromphadorhina portentosa) through bioelectrical stimulation of their neuro-mechanical system. This provides access to a novel agent that can traverse areas that are inaccessible to traditional robots. In this paper, we present a data-driven inertial navigation system that is capable of localizing cockroaches in areas where GPS is not available. We pose the navigation problem as a two-point boundary-value problem where the goal is to reconstruct a cockroach's trajectory between the starting and ending states, which are assumed to be known. We validated our technique using nine trials that were conducted in a circular arena using a biobotic agent equipped with a thorax-mounted, low-cost inertial measurement unit. Results show that we can achieve centimeter-level accuracy. This is accomplished by estimating the cockroach's velocity-using regression models that have been trained to estimate the speed and heading from the inertial signals themselves-and solving an optimization problem so that the boundary-value constraints are satisfied.


Assuntos
Desastres , Robótica , Animais , Baratas , Insetos , Locomoção
6.
Sensors (Basel) ; 20(24)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371238

RESUMO

Photoplethysmography is an extensively-used, portable, and noninvasive technique for measuring vital parameters such as heart rate, respiration rate, and blood pressure. The deployment of this technology in veterinary medicine has been hindered by the challenges in effective transmission of light presented by the thick layer of skin and fur of the animal. We propose an injectable capsule system to circumvent these limitations by accessing the subcutaneous tissue to enable reliable signal acquisition even with lower light brightness. In addition to the reduction of power usage, the injection of the capsule offers a less invasive alternative to surgical implantation. Our current prototype combines two application-specific integrated circuits (ASICs) with a microcontroller and interfaces with a commercial light emitting diode (LED) and photodetector pair. These ASICs implement a signal-conditioning analog front end circuit and a frequency-shift keying (FSK) transmitter respectively. The small footprint of the ASICs is the key in the integration of the complete system inside a 40-mm long glass tube with an inner diameter of 4 mm, which enables its injection using a custom syringe similar to the ones used with microchip implants for animal identification. The recorded data is transferred wirelessly to a computer for post-processing by means of the integrated FSK transmitter and a software-defined radio. Our optimized LED duty cycle of 0.4% at a sampling rate of 200 Hz minimizes the contribution of the LED driver (only 0.8 mW including the front-end circuitry) to the total power consumption of the system. This will allow longer recording periods between the charging cycles of the batteries, which is critical given the very limited space inside the capsule. In this work, we demonstrate the wireless operation of the injectable system with a human subject holding the sensor between the fingers and the in vivo functionality of the subcutaneous sensing on a pilot study performed on anesthetized rat subjects.


Assuntos
Fotopletismografia/instrumentação , Fotopletismografia/veterinária , Próteses e Implantes , Processamento de Sinais Assistido por Computador , Tecnologia sem Fio , Animais , Desenho de Equipamento , Projetos Piloto , Ratos , Telemetria
7.
Sensors (Basel) ; 19(3)2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30678188

RESUMO

Wearable health monitoring has emerged as a promising solution to the growing need for remote health assessment and growing demand for personalized preventative care and wellness management. Vital signs can be monitored and alerts can be made when anomalies are detected, potentially improving patient outcomes. One major challenge for the use of wearable health devices is their energy efficiency and battery-lifetime, which motivates the recent efforts towards the development of self-powered wearable devices. This article proposes a method for context aware dynamic sensor selection for power optimized physiological prediction using multi-modal wearable data streams. We first cluster the data by physical activity using the accelerometer data, and then fit a group lasso model to each activity cluster. We find the optimal reduced set of groups of sensor features, in turn reducing power usage by duty cycling these and optimizing prediction accuracy. We show that using activity state-based contextual information increases accuracy while decreasing power usage. We also show that the reduced feature set can be used in other regression models increasing accuracy and decreasing energy burden. We demonstrate the potential reduction in power usage using a custom-designed multi-modal wearable system prototype.


Assuntos
Actigrafia/instrumentação , Fontes de Energia Elétrica/economia , Telemedicina/economia , Dispositivos Eletrônicos Vestíveis/economia , Acelerometria/estatística & dados numéricos , Análise por Conglomerados , Humanos , Dispositivos Eletrônicos Vestíveis/normas
8.
Breast J ; 23(2): 159-163, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27813225

RESUMO

To investigate the effect of US performed immediately before breast conserving surgery (BCS) by radiologist accompanied by the surgeon. All patients scheduled for BCS in the last year (group 1, n = 46) were evaluated with US immediately before surgery. About 108 patients (group 2) who were treated with BCS before the study were included as the control group. Tumor size and localization, the distances between tumor-skin and tumor-pectoralis muscle fascia were noted. Re-excision rate due to positive margins was significantly lower in group 1. Statistically significant difference was detected in re-excision rates for nonpalpable tumors. Preoperative US is an effective and practical method.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Mastectomia Segmentar/métodos , Ultrassonografia Mamária , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Feminino , Humanos , Margens de Excisão , Pessoa de Meia-Idade , Músculos Peitorais , Cuidados Pré-Operatórios , Estudos Prospectivos , Adulto Jovem
9.
Ren Fail ; 38(1): 15-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26540639

RESUMO

AIM: To determine the prevalence of microalbuminuria, that is an indirect predictor of coronary artery disease, among non-obese and non-diabetic patients with fatty liver disease. MATERIAL AND METHOD: This retrospective study was carried out on non-obese (body mass index (BMI) < 30) and non-diabetic 290 female and 189 male, totally 479 cases. All subjects underwent liver ultrasonography scanning to determine the presence and stage of fatty liver disease. RESULTS: The subjects were grouped according to the ultrasound findings as follows: 182 (37.9%) cases without any fat accumulation in liver were regarded as control group; and among remaining cases, 124 (25.8%) had mild, 93 (19.4%) had moderate, and 80 (16.7%) had severe fatty liver disease. There was not any statistically significant difference between groups in regards to the age, gender, liver function tests, renal function tests or glomerular filtration rate. However urinary protein/creatinine ratio was statistically significantly higher in severe nonalcoholic fatty liver disease (NAFLD) group than the other three groups. In moderate and severe NAFLD groups, microalbuminuria was statistically significantly more common compared with the control and mild NAFLD groups. Regarding the results of multiple logistic regression analysis, presence of fatty liver disease increased the risk of microalbuminuria for 1.87 times independently from increased BMI and increased HOMA-IR values. CONCLUSION: We have determined that microalbuminuria is more prevalent among NAFLD cases compared with control cases and microalbuminuria prevalence was increasing with the advanced stages of NAFLD although two main etiologic factors of microalbuminuria, type 2 diabetes, and obesity were excluded.


Assuntos
Albuminúria/epidemiologia , Fígado Gorduroso/epidemiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Turquia/epidemiologia
10.
Clin Exp Nephrol ; 19(1): 133-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24627030

RESUMO

BACKGROUND/AIMS: Vascular access dysfunction caused by stenosis is a major complication for hemodialysis (HD) patients. However, physiopathology of late arteriovenous fistula (AVF) stenosis is still under investigation. The aim of the present study was to evaluate the association between plasma soluble EPCR (sEPCR) with serum soluble E-selectin (sE-selectin) concentration and late AVF stenosis in HD patients. METHODS: Plasma sEPCR and serum sE-selectin concentrations were measured in 94 HD patients. Using these data, we studied the association of sEPCR and sE-selectin with the presence and degree of AVF stenosis using ultrasonography and fistulogram. RESULTS: Fifty-one patients have AVF stenosis, and the others (n = 43) have patent AVF. The degree of AVF stenosis was correlated with serum sE-selectin levels (r = 0.351, p = 0.01), but not sEPCR (r = 0.075, p = 0.702). The median level of sE-selectin was statistically higher in the group of AVF stenosis than in the group of patent AVF [463.2 pg/ml (275.4-671.4) vs. 162.5 pg/ml (96.7-285.3), p = 0.001]. Increased sE-selectin levels [OR (OR) = 6.356, p = 0.015] and high levels of LDL (OR = 4.321, p = 0.044) were independent predictors of late AVF stenosis in the multivariate model. CONCLUSIONS: sE-selectin and the LDL were the most important predictors of late AVF stenosis. In addition, sE-selectin correlated with the degree of AVF stenosis. We suggested that atherosclerosis might be contributing factor for development of late AVF stenosis.


Assuntos
Antígenos CD/sangue , Fístula Arteriovenosa/patologia , Selectina E/sangue , Falência Renal Crônica/patologia , Receptores de Superfície Celular/sangue , Dispositivos de Acesso Vascular/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Digital , Fístula Arteriovenosa/diagnóstico por imagem , LDL-Colesterol/sangue , Constrição Patológica , Receptor de Proteína C Endotelial , Feminino , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Diálise Renal , Ultrassonografia Doppler em Cores , Adulto Jovem
11.
Ann Vasc Surg ; 29(4): 670-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25725273

RESUMO

BACKGROUND: Pharmacomechanical thrombectomy (PMT) has appeared as an effective treatment modality for deep venous thrombosis (DVT). The study aimed to assess the efficacy of the Cleaner™ thrombectomy device for acute DVT. METHODS: Sixteen consecutive patients presenting with extensive iliofemoral and/or femoropopliteal acute DVT and managed at our institution between February 2013 and May 2014 were retrospectively reviewed. The patients underwent PMT with the Cleaner device after insertion of vena caval filters. For underlying stenotic lesions, balloon angioplasty and/or stent placement was performed. RESULTS: PMT with the Cleaner device was successful in 14 patients with complete restoration of flow. No clinical signs of pulmonary thromboembolism was recorded after the procedure. Thrombectomy failed in 2 patients. For the rest of the patients, balloon angioplasty was performed to relieve underlying stenotic lesions. Nine of them underwent additional stenting. CONCLUSIONS: Our initial experience suggests that the Cleaner device can be used in acute DVT. However, further studies involving larger patient populations are warranted to determine long-term results.


Assuntos
Veia Femoral , Fibrinolíticos/administração & dosagem , Veia Ilíaca , Trombólise Mecânica/métodos , Veia Poplítea , Terapia Trombolítica/métodos , Ativador de Plasminogênio Tecidual/administração & dosagem , Trombose Venosa/terapia , Angioplastia com Balão/instrumentação , Desenho de Equipamento , Veia Femoral/diagnóstico por imagem , Veia Femoral/fisiopatologia , Humanos , Veia Ilíaca/diagnóstico por imagem , Veia Ilíaca/fisiopatologia , Trombólise Mecânica/instrumentação , Flebografia , Veia Poplítea/diagnóstico por imagem , Veia Poplítea/fisiopatologia , Fluxo Sanguíneo Regional , Estudos Retrospectivos , Stents , Terapia Trombolítica/instrumentação , Resultado do Tratamento , Turquia , Dispositivos de Acesso Vascular , Grau de Desobstrução Vascular , Trombose Venosa/diagnóstico , Trombose Venosa/fisiopatologia
12.
J Ultrasound Med ; 34(4): 671-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25792583

RESUMO

OBJECTIVES: This study aimed to compare sonoelastographic findings for the quadriceps tendon in patients with chronic renal failure who were in a dialysis program to findings in a control group. METHODS: Fifty-three randomly allocated patients (mean age, 54.3 years; range, 27-86 years) with chronic renal failure who were in a dialysis program 3 days a week between January and May 2012 were included. The measurements were performed in both knees of 53 patients undergoing dialysis and 25 individuals in the control group. The tendons were classified as follows: type 1, very stiff tissue (blue); type 2, stiff tissue (blue-green); and type 3, intermediate tissue (green-yellow) according to color mapping. RESULTS: The mean quadriceps tendon thicknesses in the patient group were 4.9 mm (range, 1.9-6.5 mm) for the right knee and 4.9 mm (1.4-6.5 mm) for the left knee; the values in the control group were 5.4 mm (3.6-7.0 mm) for the right knee and 5.4 mm (3.4-7.0 mm) for the left knee. The mean elasticity scores in the patient group were 3.14 (1.03-5.23) for the right knee and 3.33 (1.29-5.00) for the left knee; in the control group, the values were 3.79 (1.73-5.23) and 3.69 (1.23-5.53) for the right and left knees, respectively (right knee, P = .025; left knee, P = .018; Mann-Whitney U test). The quadriceps tendons were significantly thinner in the patient group (right knee, P = .054; left knee, P = .015; Mann-Whitney U test). CONCLUSIONS: Quadriceps tendons in patients with chronic renal failure are thinner and have lower elasticity scores compared to controls.


Assuntos
Técnicas de Imagem por Elasticidade , Falência Renal Crônica/terapia , Ligamento Patelar/diagnóstico por imagem , Ligamento Patelar/patologia , Diálise Renal , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Clin Med (Lond) ; 15(3): 248-51, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26031974

RESUMO

Common genetic mutations encountered in folate metabolism may result in increased homocysteine (Hcy) levels. It has been reported that increased serum Hcy levels may affect the intracellular fat metabolism and may cause enhanced fatty infiltration in the liver resulting in non-alcoholic fatty liver disease (NAFLD). In total, 150 patients diagnosed with FLD by ultrasound examination and 136 healthy control patients that do not have any fatty infiltration in the liver were included in the study. Patients were grouped as mild (n = 88), moderate (n = 38) or severe (n = 24) according to the stage of fatty liver in ultrasound. Serum liver function tests, Hcy, folic acid and vitamin B12 levels of the patients were studied. The genetic MTHFR C677T and A1298C polymorphisms of the patients were also evaluated. Although there was no significant difference in vitamin B12 and folic acid levels, in the severe group, Hcy levels were significantly higher than that of control and mild groups (p<0.001). By contrast, there was no significant difference in heterozygote MTHFR 677C/T and 1298A/C mutations, both MTHFR 677C/T and MTHFR 1298A/C mutations were more common in NAFLD groups compared with the control patients (p<0.001). We have determined increased Hcy levels and increased prevalence of homozygote MTHFR 677C/T and MTHFR 1298A/C mutations in patients with NAFLD compared with healthy controls. Larger studies are warranted to clarify the etiological role of the MTHFR mutations and Hcy levels in FLD.


Assuntos
Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Mutação , Hepatopatia Gordurosa não Alcoólica/genética , Adulto , Estudos de Casos e Controles , Feminino , Ácido Fólico/sangue , Predisposição Genética para Doença , Homocisteína/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/enzimologia , Vitamina B 12/sangue
14.
Proc Biol Sci ; 281(1783): 20140325, 2014 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-24695432

RESUMO

Tactile stimuli provide animals with important information about the environment, including physical features such as obstacles, and biologically relevant cues related to food, mates, hosts and predators. The antennae, the principal sensory organs of insects, house an array of sensory receptors for olfaction, gustation, audition, nociception, balance, stability, graviception, static electric fields, and thermo-, hygro- and mechanoreception. The antennae, being the anteriormost sensory appendages, play a prominent role in social interactions with conspecifics that involve primarily chemosensory and tactile stimuli. In the German cockroach (Blattella germanica) antennal contact during social interactions modulates brain-regulated juvenile hormone production, ultimately accelerating the reproductive rate in females. The primary sensory modality mediating this social facilitation of reproduction is antennal mechanoreception. We investigated the key elements, or stimulus features, of antennal contact that socially facilitate reproduction in B. germanica females. Using motor-driven antenna mimics, we assessed the physiological responses of females to artificial tactile stimulation. Our results indicate that tactile stimulation with artificial materials, some deviating significantly from the native antennal morphology, can facilitate female reproduction. However, none of the artificial stimuli matched the effects of social interactions with a conspecific female.


Assuntos
Antenas de Artrópodes/fisiologia , Blattellidae/fisiologia , Animais , Feminino , Mecanorreceptores/fisiologia , Atividade Motora , Reprodução , Facilitação Social , Tato
15.
Ren Fail ; 36(9): 1390-4, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25246339

RESUMO

OBJECTIVES: Primary cause of late arteriovenous fistula (AVF) dysfunction is venous stenosis as result of neointimal hyperplasia. The mechanism of AVF stenosis is not exactly understood. But inflammation is a contributing factor for development of AVF stenosis. Neutrophil-lymphocyte ratio (NLR) reflects systemic inflammation, and it was investigated in many diseases. The aim of this study was to investigate the relationship between NLR and AVF stenosis in chronic hemodialysis patients. MATERIALS AND METHODS: Of 593 patients applied to the department of interventional radiology between January 2011 and November 2012, a total of 108 patients meeting the appropriate criteria were included in this study. All patients were assessed with Color Doppler ultrasonography and then digital subtraction angiography was used for the patients with abnormal results. Sixty-four patients were classified as patients with AVF stenosis (group 1) and 44 patients without AVF stenosis (group 2). Routine biochemical and complete blood count values measured six months ago were recorded for all patients. RESULTS: Mean NLR (3.47 ± 0.46 vs. 2.27 ± 0.22; p < 0.001) was higher in group 1 compared to group 2, whereas high-density lipoprotein (HDL; 31.8 ± 12.6 mg/dL vs. 51.5 ± 11.9 mg/dL; p < 0.001) was lower in group 1. NLR level was correlated with degree of AVF stenosis (r = 0.625; p < 0.01). Receiver operating characteristic curve analysis showed that NLR (optimal-cut-off = 2.70) was a useful parameter in prediction of AVF stenosis (AUC = 0.893, sensitivity = 98.4% and specificity = 75%; p < 0.001). NLR level and HDL < 30 mg/dL in logistic regression analysis are independent predictors of AVF stenosis. CONCLUSIONS: For hemodialysis patients with increased level of NLR and decreased level of HDL, regular monitoring with regard to the development of AVF stenosis may be beneficial. Our study suggests that the mechanism of AVF stenosis might have similarities to that of atherosclerosis.


Assuntos
Derivação Arteriovenosa Cirúrgica , Oclusão de Enxerto Vascular/fisiopatologia , Falência Renal Crônica/terapia , Linfócitos/patologia , Neutrófilos/patologia , Diálise Renal , Idoso , Angiografia Digital , Velocidade do Fluxo Sanguíneo , Constrição Patológica , Feminino , Oclusão de Enxerto Vascular/diagnóstico por imagem , Humanos , Falência Renal Crônica/diagnóstico por imagem , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade , Ultrassonografia Doppler em Cores
16.
Artigo em Inglês | MEDLINE | ID: mdl-38437072

RESUMO

Utilizing injectable devices for monitoring animal health offers several advantages over traditional wearable devices, including improved signal-to-noise ratio (SNR) and enhanced immunity to motion artifacts. We present a wireless application-specific integrated circuit (ASIC) for injectable devices. The ASIC has multiple physiological sensing modalities including body temperature monitoring, electrocardiography (ECG), and photoplethysmography (PPG). The ASIC fabricated using the CMOS 180 nm process is sized to fit into an injectable microchip implant. The ASIC features a low-power design, drawing an average DC power of 155.3 µW, enabling the ASIC to be wirelessly powered through an inductive link. To capture the ECG signal, we designed the ECG analog frontend (AFE) with 0.3 Hz low cut-off frequency and 45-79 dB adjustable midband gain. To measure PPG, we employ an energy-efficient and safe switched-capacitor-based (SC) light emitting diode (LED) driver to illuminate an LED with milliampere-level current pulses. A SC integrator-based AFE converts the current of photodiode with a programmable transimpedance gain. A resistor-based Wheatstone Bridge (WhB) temperature sensor followed by an instrumentation amplifier (IA) provides 27-47 °C sensing range with 0.02 °C inaccuracy. Recorded physiological signals are sequentially sampled and quantized by a 10-bit analog-to-digital converter (ADC) with the successive approximation register (SAR) architecture. The SAR ADC features an energy-efficient switching scheme and achieves a 57.5 dB signal-to-noise-and-distortion ratio (SNDR) within 1 kHz bandwidth. Then, a back data telemetry transmits the baseband data via a backscatter scheme with intermediate-frequency assistance. The ASIC's overall functionality and performance has been evaluated through an in vivo experiment.

17.
IEEE J Biomed Health Inform ; 27(7): 3210-3221, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37018102

RESUMO

Cough is an important defense mechanism of the respiratory system and is also a symptom of lung diseases, such as asthma. Acoustic cough detection collected by portable recording devices is a convenient way totrack potential condition worsening for patients who have asthma. However, the data used in building current cough detection models are often clean, containing a limited set of sound categories, and thus perform poorly when they are exposed to a variety of real-world sounds which could be picked up by portable recording devices. The sounds that are not learned by the model are referred to as Out-of-Distribution (OOD) data. In this work, we propose two robust cough detection methods combined with an OOD detection module, that removes OOD data without sacrificing the cough detection performance of the original system. These methods include adding a learning confidence parameter and maximizing entropy loss. Our experiments show that 1) the OOD system can produce dependable In-Distribution (ID) and OOD results at a sampling rate above 750 Hz; 2) the OOD sample detection tends to perform better for larger audio window sizes; 3) the model's overall accuracy and precision get better as the proportion of OOD samples increase in the acoustic signals; 4) a higher percentage of OOD data is needed to realize performance gains at lower sampling rates. The incorporation of OOD detection techniques improves cough detection performance by a significant margin and provides a valuable solution to real-world acoustic cough detection problems.


Assuntos
Asma , Pneumopatias , Humanos , Tosse/diagnóstico , Acústica , Asma/diagnóstico , Espectrografia do Som/métodos
18.
Artigo em Inglês | MEDLINE | ID: mdl-38083189

RESUMO

Asthma patients' sleep quality is correlated with how well their asthma symptoms are controlled. In this paper, deep learning techniques are explored to improve forecasting of forced expiratory volume in one second (FEV1) by using audio data from participants and test whether auditory sleep disturbances are correlated with poorer asthma outcomes. These are applied to a representative data set of FEV1 collected from a commercially available sprirometer and audio spectrograms collected overnight using a smartphone. A model for detecting nonverbal vocalizations including coughs, sneezes, sighs, snoring, throat clearing, sniffs, and breathing sounds was trained and used to capture nightly sleep disturbances. Our preliminary analysis found significant improvement in FEV1 forecasting when using overnight nonverbal vocalization detections as an additional feature for regression using XGBoost over using only spirometry data.Clinical relevance- This preliminary study establishes up to 30% improvement of FEV1 forecasting using features generated by deep learning techniques over only spirometry-based features.


Assuntos
Asma , Humanos , Adolescente , Asma/diagnóstico , Espirometria/métodos , Testes de Função Respiratória , Volume Expiratório Forçado , Tosse
19.
Artigo em Inglês | MEDLINE | ID: mdl-38082824

RESUMO

Early detection of cognitive decline is essential to study mild cognitive impairment and Alzheimer's Disease in order to develop targeted interventions and prevent or stop the progression of dementia. This requires continuous and longitudinal assessment and tracking of the related physiological and behavioral changes during daily life. In this paper, we present a low cost and low power wearable system custom designed to track the trends in speech, gait, and cognitive stress while also considering the important human factor needs such as privacy and compliance. In the form factors of a wristband and waist-patch, this multimodal, multi-sensor system measures inertial signals, sound, heart rate, electrodermal activity and pulse transit time. A total power consumption of 2.6 mW without any duty cycling allows for more than 3 weeks of run time between charges when 1500 mAh batteries are used.Clinical Relevance- Much earlier detection of Alzheimer's disease and related dementias may be possible by continuous monitoring of physiological and behavioral state using application specific wearable sensors during the activities of daily life.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Dispositivos Eletrônicos Vestíveis , Humanos , Doença de Alzheimer/diagnóstico , Fala , Disfunção Cognitiva/diagnóstico , Marcha , Diagnóstico Precoce
20.
Pol J Radiol ; 77(4): 65-6, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23269940

RESUMO

BACKGROUND: Persistent left superior vena cava is a rare but important congenital vascular anomaly. However, PLSVC with absent RSVC (isolated PLSVC) is a very rare venous malformation We report on a rare case of persistent left superior vena cava (PLSVC) with absent right superior vena cava (RSVC). CASE REPORT: This venous malformation was identified incidentally in a 69-year-old woman during chest multi-detector computed tomography (MDCT). On chest MDCT, the SVC was noted on the left side. A bridging vein drained the right jugular and right subclavian veins and joined the left brachiocephalic vein in order to form the PLSVC, which descended on the left side of the mediastinum and drained into the left atrium (LA). The patient had no additional cardiac anomaly. CONCLUSIONS: Isolated PLSVC is usually asymptomatic but it can pose difficulties for establishing central venous access, pacemaker implantation and cardiothoracic surgery. This condition is also associated with an increased incidence of congenital heart disease, arrhythmias and conduction disturbances. A wide spectrum of clinicians should be aware of this anomaly, its variations and possible complications.

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