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1.
Poult Sci ; 103(3): 103402, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38266435

RESUMEN

The present study was conducted to assess the animal welfare status of broiler chickens raised in conventional and welfare-certified farms. One conventional farm (30,000 birds/house, 1,488 m2/house, 2 houses) and one animal welfare-certified farm (32,000 birds/house, 1,920 m2/house, 2 houses) were selected to measure productivity, stress responses, and animal welfare indicators in 3 broiler flocks (2 farms/season, n = 6 flocks/farm type) during summer, autumn, and spring. Upon farm visits, body weight, uniformity, and animal welfare indicators (i.e., fecal and feather corticosterone, footpad dermatitis, hock burn, feather dirtiness, and gait score) were measured at 26 d posthatch. Also, moisture, nitrogen, and pH of litter, light intensity, ammonia concentration, and body surface temperature of head, chest, and legs were measured. There was no difference in body weight and uniformity between farm types. Fecal corticosterone concentrations were higher (P = 0.021) in welfare-certified vs. conventional farm, but no significant difference was found in feather corticosterone. Welfare-certified vs. conventional farm had lower percentages of hock burn (P = 0.018), feather dirtiness scores (P = 0.009), and gait score (P = 0.040), and there was no difference in footpad dermatitis. Nitrogen content in litter samples tended to be higher in conventional vs. welfare-certified farms (P = 0.094), and there was no difference in moisture and pH between farm types. Ammonia concentration within the broiler houses was not different between 2 farms. However, animal welfare farm was found to be brighter than conventional farm (P < 0.001). The body surface temperature of head, chest, and legs was not different between farm types. In conclusion, the welfare-certified farm had higher welfare measures, including lower hock burn, feather dirtiness, and gait score, confirming an overall improvement in welfare indicators. However, the observation on the elevated feather corticosterone noted in welfare vs. conventionally raised chickens warrants further studies.


Asunto(s)
Dermatitis , Enfermedades de las Aves de Corral , Animales , Pollos/fisiología , Granjas , Amoníaco , Corticosterona , Crianza de Animales Domésticos , Bienestar del Animal , Peso Corporal , Dermatitis/etiología , Dermatitis/veterinaria , Nitrógeno
2.
Med Phys ; 50(10): 6118-6129, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37469146

RESUMEN

BACKGROUND: Positron probes can accurately localize malignant tumors by directly detecting positrons emitted from positron-emitting radiopharmaceuticals that accumulate in malignant tumors. In the conventional method for direct positron detection, multilayer scintillator detection and pulse shape discrimination techniques are used. However, some γ-rays cannot be distinguished by conventional methods. Accordingly, these γ-rays are misidentified as positrons, which may increase the error rate of positron detection. PURPOSE: To analyze the energy distribution in each scintillator of the multilayer scintillator detector to distinguish true positrons and γ-rays and to improve the positron detection algorithm by discriminating true and false positrons. METHODS: We used Autoencoder, an unsupervised deep learning architecture, to obtain the energy distribution data in each scintillator of the multilayer scintillator detector. The Autoencoder was trained to separate the combined signals generated from the multilayer scintillator detector into two signals of each scintillator. An energy window was then applied to the energy distribution obtained using the trained Autoencoder to distinguish true positrons from false positrons. Finally, the performance of the proposed method and conventional positron detection algorithm was evaluated in terms of the sensitivity and error rate for positron detection. RESULTS: The energy distribution map obtained using the trained Autoencoder was proven to be similar to that of the simulated results. Furthermore, the proposed method demonstrated a 29.79% (+0.42%p) increase in positron detection sensitivity compared to the conventional method, both having an equal error rate of 0.48%. However, when both methods were set to have the same sensitivity of 1.83%, the proposed method had an error rate that was 25.0% (-0.16%p) lower than that of the conventional method. CONCLUSIONS: We proposed and developed an Autoencoder-based positron detection algorithm that can discriminate between true and false positrons with a smaller error rate than conventional methods. We verified that the proposed method could increase the positron detection sensitivity while maintaining a low error rate compared to the conventional method. If the proposed algorithm is implemented in handheld positron detection probes or cameras, diseases such as cancers can be more accurately localized in a shorter time compared with using traditional methods.


Asunto(s)
Aprendizaje Profundo , Neoplasias , Humanos , Tomografía de Emisión de Positrones/métodos , Partículas beta , Algoritmos
3.
Sensors (Basel) ; 23(5)2023 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-36905074

RESUMEN

In the medical field, it is delicate to anticipate good performance in using deep learning due to the lack of large-scale training data and class imbalance. In particular, ultrasound, which is a key breast cancer diagnosis method, is delicate to diagnose accurately as the quality and interpretation of images can vary depending on the operator's experience and proficiency. Therefore, computer-aided diagnosis technology can facilitate diagnosis by visualizing abnormal information such as tumors and masses in ultrasound images. In this study, we implemented deep learning-based anomaly detection methods for breast ultrasound images and validated their effectiveness in detecting abnormal regions. Herein, we specifically compared the sliced-Wasserstein autoencoder with two representative unsupervised learning models autoencoder and variational autoencoder. The anomalous region detection performance is estimated with the normal region labels. Our experimental results showed that the sliced-Wasserstein autoencoder model outperformed the anomaly detection performance of others. However, anomaly detection using the reconstruction-based approach may not be effective because of the occurrence of numerous false-positive values. In the following studies, reducing these false positives becomes an important challenge.


Asunto(s)
Aprendizaje Profundo , Ultrasonografía Mamaria , Femenino , Humanos , Ultrasonografía Mamaria/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Ultrasonografía , Diagnóstico por Computador/métodos
4.
Animals (Basel) ; 12(24)2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36552432

RESUMEN

This study was performed to investigate the effects of apparent metabolizable energy (AMEn) and protein levels on laying performance, egg quality, blood parameters, blood biochemistry, and apparent total tract digestibility of energy and nutrients in diets fed to laying hens in an aviary system. A total of 560 Hy-Line Brown laying hens (age = 30 week) were distributed in a completely randomized experimental design in 2 × 2 factorial arrangements with 2 metabolizable energy levels (2700 and 2800 kcal AMEn/kg) and 2 protein levels (16.5 and 14.5% CP). Four treatments and four replicates of 40 birds each (stocking density = 15 birds/m2) were prepared. Results revealed no significant interaction between AMEn and CP in the diet in terms of egg production, floor eggs, broken and dirty egg production, egg mass, feed intake, and feed conversion ratio of laying hens. However, egg weight was affected. As dietary energy and CP levels (2800 kcal of AMEn/kg and 16.5% CP) increased, egg weight increased (p < 0.05). Egg weight, feed intake, and feed conversion ratio significantly differed (p < 0.05) as the energy content in the feed increased. Ether extract significantly varied (p < 0.05) as the energy content in the feed increased. In conclusion, laying performance and egg quality of Hy-Line Brown laying hens in the middle stage of egg production (30 to 50 weeks) were not affected by different dietary energy and protein levels, but feed intake decreased with an increasing level of AMEn in diets. Ether extract significantly varied as the energy content in the feed increased.

5.
Sci Rep ; 12(1): 16797, 2022 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-36207389

RESUMEN

This prospective, randomized controlled trial evaluated the effect of neostigmine for intraoperative neuromonitoring (IONM) during thyroid surgery. Forty subjects undergoing thyroidectomy with IONM, randomized into neostigmine administration after tracheal intubation (Group N, n = 20) or control treatment with normal saline (Group C, n = 20), completed the trial. Electromyography amplitudes of the vagus nerve (V1) were recorded before thyroid dissection. The time from the initial V1 signal check to successful V1 stimulation was recorded. In Group N, all the patients had a successful V1 signal at the first check, whereas ten (50%) patients in Group C had a time delay between the initial V1 check and successful V1 (p < 0.001). The mean delay time among the delayed patients in Group C was 11.2 ± 1.4 min. The mean time from skin incision to successful V1 stimulation was significantly shorter in Group N than in Group C (15.4 ± 2.4 min vs. 19.9 ± 5.7 min, p = 0.003). In Groups N and C, the mean V1 amplitudes were 962.2 ± 434.5 µV vs. 802.3 ± 382.7 µV (p = 0.225), respectively, and the mean R1 amplitudes were 1240.0 ± 836.5 µV vs. 1023.4 ± 455.8 µV (p = 0.316), respectively. There was one bucking event in Group N. In conclusion, neostigmine administration immediately after tracheal intubation can be useful to reverse neuromuscular blockade for successful IONM in thyroid surgeries.


Asunto(s)
Neostigmina , Glándula Tiroides , Electromiografía , Humanos , Intubación Intratraqueal , Estudios Prospectivos , Solución Salina , Glándula Tiroides/inervación , Glándula Tiroides/cirugía
6.
Animals (Basel) ; 12(18)2022 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-36139238

RESUMEN

In this study, we examined the effect of diets supplemented with organic and inorganic mineral premixes on the laying performance and eggshell quality of aged laying hens. A total of 600 68-week-old Hy-Line Brown laying hens were randomly assigned to 1 of 3 dietary treatments, repeated 5 times: Mash type basal diet, basal diet supplemented with an inorganic mineral premix (1.0 g/kg), and basal diet supplemented with an organic mineral premix (1.8 g/kg). The results showed that eggshell strength was higher (p < 0.01) in the inorganic mineral diet group than in the organic mineral and basal diet groups. Further, the levels of Fe and Mn in the liver were higher (p < 0.05) in the inorganic and organic mineral diet groups than in the basal diet group. The concentrations of Fe and Mg in the spleen were different (p < 0.05) among the treatment groups, with the highest levels reported in the organic mineral premix group. The concentrations of Cu, Zn, and Mn in the eggshell were different (p < 0.05) among the groups, with the highest levels reported in the inorganic and organic mineral premix diet groups. In conclusion, a diet containing organic mineral premix improved eggshell strength and had no detrimental effect on the laying performance of aged laying hens.

7.
Global Spine J ; : 21925682221110828, 2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35730759

RESUMEN

STUDY DESIGNS: Retrospective Observational StudyObjectives: To compare the incidence of POD after propofol- and sevoflurane-based anesthesia in elderly patients undergoing spine surgery. METHODS: In this study, the medical records of elderly patients ≥ 65 years of age who underwent spine surgery under total intravenous anesthesia with propofol or inhalational anesthesia with sevoflurane were reviewed. The primary outcome was the incidence of POD after propofol- and sevoflurane-based anesthesia. Secondary outcomes included postoperative 30-day complications, length of postoperative hospital stay, associations of patient characteristics, and surgery- and anesthesia-related data with the development of POD, and associations of anesthetics with clinical outcomes such as postoperative 30-day complications, and length of postoperative hospital stay. RESULTS: Of the 281 patients, POD occurred in 29 patients (10.3%). POD occurred more frequently in the sevoflurane group than in the propofol group (15.7% vs. 5.0%, respectively; P=.003). The multivariable logistic regression analysis showed that sevoflurane-based anesthesia was associated with an increased risk of POD compared with propofol-based anesthesia (odds ratio [OR], 4.120; 95% confidence interval [CI], 1.549-10.954; P = .005), whereas anesthetics were not associated with postoperative 30-day complications and the length of postoperative hospital stay. Older age (OR, 1.242 CI, 1.130-1.366; P < .001) and higher mean pain score at postoperative day 1 (OR, 1.338 CI, 1.056-1.696; P = .016) were also associated with an increased risk of POD. CONCLUSIONS: Propofol-based anesthesia was associated with a lower incidence of POD than sevoflurane-based anesthesia in elderly patients after spine surgery.

8.
Animals (Basel) ; 12(9)2022 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-35565592

RESUMEN

BACKGROUND: Looking for alternative omega-3 sources in broiler nutrition, microalgae began to get attention. We suspected that schizochytrium might play a similar role as other omega-3 sources that have been used before. METHODS: 20 g/kg schizochytrium powder (SP), salmon oil (SO), and flaxseed oil (FO) in each of the three treatment groups were supplemented in the basal diet (CON), and productive performance, carcass traits, and thigh meat quality of broilers were evaluated. RESULTS: There was a significantly higher weight gain in the SP treatment compared to the other groups, but no difference was found in feed intake and feed conversion ratio. Thiobarbituric acid reactive substance values increased during storage in all the treatments but were significantly lower for SP than for SO and FO after 7 days of storage. Among the ω-3 fatty acids (FAs), α-linolenic acid increased the most in the FO treatment, eicosapentaenoic acid increased the most in the SO treatment, and docosahexaenoic acid increased the most in the SP treatment in thigh meat, reflecting the FA composition of the lipid source diets. CONCLUSIONS: We suggested that all the dietary ω-3 FA sources could improve the FA composition of chicken meat and our results indicated the possibility to supplement broiler diets with 2% level of SP, SO, and FO as ω-3 FA sources to produce meat with a good nutritional quality for consumer's health benefits.

9.
Food Sci Anim Resour ; 42(1): 128-141, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35028579

RESUMEN

Compared to the conventional farms (CF) rearing of broilers, the rearing management of animal welfare-certified farms (AF) must provide low stocking density, perch, air regulation, and feeding plant-based protein. This study aimed to compare the effects of rearing management in CF and AF on blood parameters, meat quality, and bioactive compound content in Ross 308 broiler chickens at the farm level before transportation to slaughterhouses. Blood and meat samples were obtained at 28-35-day-old chickens from three CF and three AF. In blood samples, low-density lipoprotein cholesterol (p<0.05), triglyceride (p<0.001), glucose (p<0.01), total protein (p<0.001), albumin (p<0.01), and white blood cell (p<0.001) levels as well as the heterophil/ lymphocyte ratio [stress index (SI), p<0.001] were lower in broilers from AF than in CF. In meat samples, shear force (p<0.001, p<0.05), and carnosine contents (p<0.001, p<0.05) in both breast and thigh meat from AF were higher than those in meat from CF. The contents of linoleic acid (p<0.001), α-linolenic acid (p<0.001), and eicosapentaenoic acid (p<0.05) were higher in the samples from AF than those from CF. This study reveals that such differences are influenced by the different rearing factors in nutrition, housing, and management practices between CF and AF. Supplementation of plant-based protein and enough space to move due to lower stocking density accounts for the large differences between them. These results can be used as preliminary data showing that the AF system reduces the SI and enhances carnosine and polyunsaturated fatty acids levels in chicken meat at the farm level before transportation.

10.
Animals (Basel) ; 11(12)2021 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-34944285

RESUMEN

The aim of this study was to evaluate the suitability of fermented oat (FO) and black soldier fly larva (BSFL) as food ingredients for dogs. A total of 20 spayed female dogs were divided into four treatment groups, with 5 dogs per group. The four treatment groups consisted of a control group, a diet with 10% FO, one with 5% BSFL, and one with 10% FO and 5% BSFL, and each experimental food was fed for 12 weeks. The feeding of FO and/or BSFL did not affect the daily food intake, body weight, body condition score, fecal score, or skin condition of the dogs. In all the experimental groups, no significant differences in serum IgG, IL-10, or TNF-α levels were observed upon the feeding of FO and/or BSFL. Some hematological (white blood cell and basophils) and serum biochemical parameters (phosphorous, globulin, and alkaline phosphatase) showed significant differences with FO and/or BSFL feeding compared to the control group, but they were within the normal reference range. No adverse clinical signs related to these parameters being affected by FO and BSFL were observed. The feeding of BSFL for 12 weeks reduced the serum cholesterol level (p < 0.05) at the end of the experiment. Our findings suggest the suitability of FO and BSFL as food materials for dogs.

11.
Sci Rep ; 11(1): 24382, 2021 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-34934144

RESUMEN

Conventional deep learning (DL) algorithm requires full supervision of annotating the region of interest (ROI) that is laborious and often biased. We aimed to develop a weakly-supervised DL algorithm that diagnosis breast cancer at ultrasound without image annotation. Weakly-supervised DL algorithms were implemented with three networks (VGG16, ResNet34, and GoogLeNet) and trained using 1000 unannotated US images (500 benign and 500 malignant masses). Two sets of 200 images (100 benign and 100 malignant masses) were used for internal and external validation sets. For comparison with fully-supervised algorithms, ROI annotation was performed manually and automatically. Diagnostic performances were calculated as the area under the receiver operating characteristic curve (AUC). Using the class activation map, we determined how accurately the weakly-supervised DL algorithms localized the breast masses. For internal validation sets, the weakly-supervised DL algorithms achieved excellent diagnostic performances, with AUC values of 0.92-0.96, which were not statistically different (all Ps > 0.05) from those of fully-supervised DL algorithms with either manual or automated ROI annotation (AUC, 0.92-0.96). For external validation sets, the weakly-supervised DL algorithms achieved AUC values of 0.86-0.90, which were not statistically different (Ps > 0.05) or higher (P = 0.04, VGG16 with automated ROI annotation) from those of fully-supervised DL algorithms (AUC, 0.84-0.92). In internal and external validation sets, weakly-supervised algorithms could localize 100% of malignant masses, except for ResNet34 (98%). The weakly-supervised DL algorithms developed in the present study were feasible for US diagnosis of breast cancer with well-performing localization and differential diagnosis.


Asunto(s)
Algoritmos , Neoplasias de la Mama/diagnóstico , Mama/patología , Aprendizaje Profundo , Interpretación de Imagen Asistida por Computador/métodos , Redes Neurales de la Computación , Ultrasonografía Mamaria/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Mama/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Estudios de Casos y Controles , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Pronóstico , Curva ROC , Estudios Retrospectivos , Adulto Joven
12.
Am J Emerg Med ; 50: 561-565, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34555660

RESUMEN

OBJECTIVE: Head and shoulder positioning may affect cross-sectional area (CSA) and location of the subclavian vein (SCV). We investigated the CSA of the SCV and the depth of the SCV, depending on the head and shoulder positions. METHODS: In 24 healthy obese volunteers, the short axis ultrasound images of the SCV and adjacent structures were obtained in three different head positions (neutral, 30° turned to the contralateral side, and 30° turned to the ipsilateral side) and two different shoulder positions (neutral and lowered). Images of the right and left SCVs were obtained in the supine and Trendelenburg positions. Subsequently, the CSA and depth of the SCV were measured. RESULTS: Significant differences were found in the CSA of the SCV in different head positions (30° turned to contralateral side vs. neutral: -0.06 cm2, 95% confidence interval [CI], -0.10 to -0.02; Pcorrected = 0.002, 30° turned to contralateral side vs. 30° turned to ipsilateral side: -0.16 cm2, 95% CI, -0.22 to -0.11; Pcorrected < 0.001, Neutral vs. 30° turned to ipsilateral side: -0.10 cm2, 95% CI, -0.14 to -0.07; Pcorrected < 0.001). The CSA of the SCV was significantly different, depending on shoulder positions (neutral vs. lowered: 0.44 cm2, 95% CI, 0.33 to 0.54; Pcorrected < 0.001), and body position (supine vs. Trendelenburg: -0.15 cm2, 95% CI, -0.19 to -0.12; Pcorrected < 0.001). However, the depth of the SCV did not differ with respect to head, shoulder, and body positions. CONCLUSIONS: Ipsilateral 30° head rotation, neutral shoulder position, and Trendelenburg position significantly enhanced the CSA of the SCV in obese participants.


Asunto(s)
Cateterismo Venoso Central , Inclinación de Cabeza , Obesidad/diagnóstico por imagen , Posicionamiento del Paciente , Vena Subclavia/diagnóstico por imagen , Posición Supina , Adulto , Índice de Masa Corporal , Femenino , Cabeza , Humanos , Masculino , Persona de Mediana Edad , Hombro , Ultrasonografía
13.
Anesth Analg ; 133(2): 491-499, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34081034

RESUMEN

BACKGROUND: Cricoid pressure has been used as a component of the rapid sequence induction and intubation technique. However, concerns have been raised regarding the effectiveness and safety of cricoid pressure. Paratracheal pressure, a potential alternative to cricoid pressure to prevent regurgitation of gastric contents or aspiration, has been studied to be more effective to cricoid pressure in preventing gastric insufflation during positive pressure ventilation. However, to adopt paratracheal compression into our practice, adverse effects including its effect on the glottic view during direct laryngoscopy should be studied. We conducted a randomized, double-blind, noninferiority trial comparing paratracheal and cricoid pressures for any adverse effects on the view during direct laryngoscopy, together with other secondary outcome measures. METHODS: In total, 140 adult patients undergoing general anesthesia randomly received paratracheal pressure (paratracheal group) or cricoid pressure (cricoid group) during anesthesia induction. The primary end point was the incidence of deteriorated laryngoscopic view, evaluated by modified Cormack-Lehane grade with a predefined noninferiority margin of 15%. Secondary end points included percentage of glottic opening score, ease of mask ventilation, change in ventilation volume and peak inspiratory pressure during mechanical mask ventilation, ease of tracheal intubation, and resistance encountered while advancing the tube into the glottis. The position of the esophagus was assessed by ultrasound in both groups to determine whether pressure applied to the respective area would be likely to result in esophageal compression. All secondary outcomes were tested for superiority, except percentage of glottic opening score, which was tested for noninferiority. RESULTS: Paratracheal pressure was noninferior to cricoid pressure regarding the incidence of deterioration of modified Cormack-Lehane grade (0% vs 2.9%; absolute risk difference, -2.9%; 95% confidence interval, -9.9 to 2.6, P <.0001). Mask ventilation, measured on an ordinal scale, was found to be easier (ie, more likely to have a lower score) with paratracheal pressure than with cricoid pressure (OR, 0.41; 95% confidence interval, 0.21-0.79; P = .008). The increase in peak inspiratory pressure was significantly less in the paratracheal group than in the cricoid group during mechanical mask ventilation (median [min, max], 0 [-1, 1] vs 0 [-1, 23]; P = .001). The differences in other secondary outcomes were nonsignificant between the groups. The anatomical position of the esophagus was more suitable for compression in the paratracheal region, compared to the cricoid cartilage region. CONCLUSIONS: Paratracheal pressure was noninferior to cricoid pressure with respect to the effect on glottic view during direct laryngoscopy.


Asunto(s)
Anestesia General , Cartílago Cricoides , Glotis , Intubación Intratraqueal , Laringoscopía , Respiración Artificial , Tráquea , Adulto , Anciano , Anestesia General/efectos adversos , Cartílago Cricoides/diagnóstico por imagen , Método Doble Ciego , Procedimientos Quirúrgicos Electivos , Esófago/diagnóstico por imagen , Femenino , Humanos , Intubación Intratraqueal/efectos adversos , Intubación Intratraqueal/instrumentación , Laringoscopía/efectos adversos , Laringoscopía/instrumentación , Masculino , Persona de Mediana Edad , Presión , Estudios Prospectivos , Respiración Artificial/efectos adversos , Respiración Artificial/instrumentación , Seúl , Tráquea/diagnóstico por imagen , Resultado del Tratamiento , Ultrasonografía
14.
Opt Express ; 29(2): 751-760, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33726305

RESUMEN

Surface modification of ceramic Ce-doped Gd3Al2Ga3O12 (Ce:GAGG) was performed by exposing small samples to anhydrous phosphoric acid (H3PO4) under different conditions (temperature and duration) to investigate the effects of chemical polishing treatment. When coupled to a photomultiplier tube (PMT) and used as a radiation detector, chemical treatment for 3 min at 190 °C improved the light (signal) output by 24.8% and energy resolution by 2.5% (percentage point), respectively. This can be attributed to a reduction in surface roughness that enhanced optical properties. Thus, chemical polishing could be a low-cost alternative to mechanical polishing especially for small or complex shaped ceramic scintillators.

15.
Sensors (Basel) ; 21(4)2021 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-33557045

RESUMEN

We propose an integrated front-end data acquisition circuit for a hybrid ultrasound (US)-gamma probe. The proposed circuit consists of three main parts: (1) a preamplifier for the gamma probe, (2) a preprocessing analog circuit for the US, and (3) a digitally controlled analog switch. By exploiting the long idle time of the US system, an analog switch can be used to acquire data of both systems using a single output channel simultaneously. On the nuclear medicine (NM) gamma probe side, energy resolutions of 18.4% and 17.5% were acquired with the standalone system and with the proposed switching circuit, respectively, when irradiated with a Co-57 radiation source. Similarly, signal-to-noise ratios of 14.89 and 13.12 dB were achieved when US echo signals were acquired with the standalone system and with the proposed switching circuit, respectively. Lastly, a combined US-gamma probe was used to scan a glass target and a sealed radiation source placed in a water tank. The results confirmed that, by using a hybrid US-gamma probe system, it is possible to distinguish between the two objects and acquire structural information (ultrasound) alongside molecular information (gamma radiation source).

16.
Ultrasonography ; 40(2): 183-190, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33430577

RESUMEN

Although breast ultrasonography is the mainstay modality for differentiating between benign and malignant breast masses, it has intrinsic problems with false positives and substantial interobserver variability. Artificial intelligence (AI), particularly with deep learning models, is expected to improve workflow efficiency and serve as a second opinion. AI is highly useful for performing three main clinical tasks in breast ultrasonography: detection (localization/ segmentation), differential diagnosis (classification), and prognostication (prediction). This article provides a current overview of AI applications in breast ultrasonography, with a discussion of methodological considerations in the development of AI models and an up-to-date literature review of potential clinical applications.

17.
Sensors (Basel) ; 22(1)2021 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-35009760

RESUMEN

Recently, the amount of attention paid towards convolutional neural networks (CNN) in medical image analysis has rapidly increased since they can analyze and classify images faster and more accurately than human abilities. As a result, CNNs are becoming more popular and play a role as a supplementary assistant for healthcare professionals. Using the CNN on portable medical devices can enable a handy and accurate disease diagnosis. Unfortunately, however, the CNNs require high-performance computing resources as they involve a significant amount of computation to process big data. Thus, they are limited to being used on portable medical devices with limited computing resources. This paper discusses the network quantization techniques that reduce the size of CNN models and enable fast CNN inference with an energy-efficient CNN accelerator integrated into recent mobile processors. With extensive experiments, we show that the quantization technique reduces inference time by 97% on the mobile system integrating a CNN acceleration engine.


Asunto(s)
Redes Neurales de la Computación , Humanos
18.
Nanoscale ; 10(25): 12087-12092, 2018 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-29911713

RESUMEN

Silver (Ag) nanowires (NWs) are promising building blocks for flexible transparent electrodes, which are key components in fabricating soft electronic devices such as flexible organic light emitting diodes (OLEDs). Typically, Ag NWs have been synthesized using a polyol method, but it still remains a challenge to produce high-aspect-ratio Ag NWs via a simple and rapid process. In this work, we developed a modified polyol method and newly found that the addition of propylene glycol to ethylene glycol-based polyol synthesis facilitated the growth of Ag NWs, allowing the rapid production of long Ag NWs with high aspect ratios of about 2000 in a high yield (∼90%) within 5 min. Transparent electrodes fabricated with our Ag NWs exhibited performance comparable to that of an indium tin oxide-based electrode. With these Ag NWs, we successfully demonstrated the fabrication of a large-area flexible OLED with dimensions of 30 cm × 15 cm using a roll-to-roll process.

19.
Sensors (Basel) ; 18(6)2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29865168

RESUMEN

This paper presents a 612⁻1152 MHz Injection-Locked Frequency Multiplier (ILFM). The proposed ILFM is used to send an input signal to a receiver in only the I/Q mismatch calibration mode. Adopting a Phase-Locked Loop (PLL) to calibrate the receiver places a burden on this system because of the additional area and power consumption that is required. Instead of the PLL, to satisfy high-frequency, low-jitter and low-area requirements, a Ring Oscillator is adopted in the system. The free-running frequency of the ILFM is automatically and digitally calibrated to reflect the frequency of the injected signal from the harmonics of the reference clock. To control the frequency of the ILFM, the load current is digitally tuned with a 6-bit digital control signal. The proposed ILFM locks to the target frequency using a digitally controlled Frequency Locked Loop (FLL). This chip is fabricated using 1-poly 6-metal 0.18 µm CMOS and has achieved the wide tuning range of 612⁻1152 MHz. The power consumption is 0.95 mW from a supply voltage of 1.8 V. The measured phase noise of the ILFM is -108 dBc/Hz at a 1 MHz offset.

20.
Opt Express ; 24(26): 29483-29495, 2016 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-28059335

RESUMEN

Light out-coupling of organic light-emitting diodes (OLEDs) with silver (Ag)-nanomesh electrodes was examined. Experimental results for the OLEDs with nine different nanomesh dimensions were compared with simulation results to elucidate the dimensional effect of the nanomesh on the light out-coupling behavior of the devices. The Ag-nanomesh electrodes did not only increase the transparency of the Ag electrode due to periodic nanoholes but also enhanced light extraction from surface plasmon polaritons and substrate/waveguide modes in the devices. The simulation results show similar trends with the experimental results for the optical transmittance, emission spectrum, and efficiency enhancement. With a nanomesh dimension of 480 nm period and 50% fill factor, the OLEDs with the Ag-nanomesh electrode showed 1.66 times higher efficiency than those with a planar Ag electrode did. Using our validated simulation, we construct an external quantum efficiency map in full ranges of the period and fill factor of the Ag-nanomesh electrode to find out the optimum nanomesh dimension.

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