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1.
J Org Chem ; 89(3): 2032-2038, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38226644

RESUMEN

The construction of a C-C bond by cross-coupling of two different C-H bonds with the release of hydrogen gas represents an ideal yet challenging bond formation strategy. Herein, we report a photocatalytic metal-free cross-coupling of benzylic and aldehydic C-H bonds by synergistic catalysis of organophotocatalyst 4CzIPN and a thiol, which affords the corresponding α-aryl ketones in acceptable yields along with hydrogen evolution. The mechanistic investigation indicates a radical-radical coupling to give an intermediary alcohol, followed by an acceptorless alcohol dehydrogenation.

2.
Health Qual Life Outcomes ; 22(1): 3, 2024 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-38185647

RESUMEN

BACKGROUND: Eye cancer is a serious eye disease that threatens patients' lives. In the past decade, there have been more and more studies on eye cancer. From the recently published eye cancer literature review, it can be seen that the two most popular research hotspots are retinoblastoma (RB) and uveal melanoma (UM) [1, 2]. Although several studies have assessed QOL in different types of eye cancer patients, a study that synthesizes the factors influencing QOL in eye cancer patients is yet to be undertaken. This study aimed to review and evaluate the literature related to the QOL of RB and UM survivors, and provide a synthesis of the current evidence on the impact of the two types of eye cancer on the overall QOL of patients. METHODS: Eight databases (APA Psych Articles, CINAHL Complete, Health Source: Nursing/Academic Edition, MEDLINE Complete, Scopus, Cochrane Library, PubMed, and Registers (Clinicaltrials.gov.)) were searched between January 2012 and December 2022 for English, peer-reviewed quantitative original studies within this review. All publications were screened using the Preferred Reporting Items for Systematic Review and Meta-Analyses reporting guidelines. The methodological quality of the reviews was assessed using the Joanna Briggs Institute Critical Appraisal Checklists. The findings were summarised and tabulated accordingly. RESULTS: Seventeen articles were analysed. Among them, 14 articles on patients with UM, and three articles on patients with RB using 18 different types of measurement tools were included. Eight researchers claimed that the overall QOL of patients with eye cancer was better than or similar to that of the general healthy population. However, nine studies indicated that these patients had poorer QOL than others. Many factors affect QOL, including treatment, sex, and age. CONCLUSION: This systematic review identified the QOL levels and several factors that influence the QOL of ocular cancer patients worldwide, due to the variability in quality of the studies, it also showed the need for further research to assess factors affecting long-term QOL outcomes in RB and UM survivors. Simultaneously, it clarified the necessity and importance of developing standardized and complete assessment tools to compare QOL in different countries. Early interventions can be developed to improve the survivors' QOL by identifying potential deficits in specific areas.


Asunto(s)
Neoplasias del Ojo , Neoplasias de la Úvea , Humanos , Estado de Salud , Calidad de Vida
3.
J Nanobiotechnology ; 22(1): 484, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39138477

RESUMEN

BACKGROUND: Inflammatory bowel disease (IBD) is a progressive and debilitating inflammatory disease of the gastrointestinal tract (GIT). Despite recent advances, precise treatment and noninvasive monitoring remain challenging. METHODS: Herein, we developed orally-administered, colitis-targeting and hyaluronic acid (HA)-modified, core-shell curcumin (Cur)- and cerium oxide (CeO2)-loaded nanoprobes (Cur@PC-HA/CeO2 NPs) for computed tomography (CT) imaging-guided treatment and monitoring of IBD in living mice. RESULTS: Following oral administration, high-molecular-weight HA maintains integrity with little absorption in the upper GIT, and then actively accumulates at local colitis sites owing to its colitis-targeting ability, leading to specific CT enhancement lasting for 24 h. The retained NPs are further degraded by hyaluronidase in the colon to release Cur and CeO2, thereby exerting anti-inflammatory and antioxidant effects. Combined with the ability of NPs to regulate intestinal flora, the oral NPs result in substantial relief in symptoms. Following multiple treatments, the gradually decreasing range of the colon with high CT attenuation correlates with the change in the clinical biomarkers, indicating the feasibility of treatment response and remission. CONCLUSION: This study provides a proof-of-concept for the design of a novel theranostic integration strategy for concomitant IBD treatment and the real-time monitoring of treatment responses.


Asunto(s)
Cerio , Curcumina , Ácido Hialurónico , Enfermedades Inflamatorias del Intestino , Nanopartículas , Nanomedicina Teranóstica , Animales , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Ratones , Cerio/química , Curcumina/farmacología , Curcumina/química , Curcumina/uso terapéutico , Nanomedicina Teranóstica/métodos , Administración Oral , Nanopartículas/química , Ácido Hialurónico/química , Hialuronoglucosaminidasa/metabolismo , Tomografía Computarizada por Rayos X , Ratones Endogámicos C57BL , Colon/diagnóstico por imagen , Colon/patología , Colon/metabolismo , Humanos , Colitis/tratamiento farmacológico
4.
BMC Pediatr ; 24(1): 186, 2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38491421

RESUMEN

BACKGROUND: The aim of this study was to investigate the clinical features and treatment options for pediatric adrenal incidentalomas(AIs) to guide the diagnosis and treatment of these tumors. METHODS: The clinical data of AI patients admitted to our hospital between December 2016 and December 2022 were collected and retrospectively analyzed. All patients were divided into neonatal and nonneonatal groups according to their age at the time of the initial consultation. RESULTS: In the neonatal group, 13 patients were observed and followed up, and the masses completely disappeared in 8 patients and were significantly reduced in size in 5 patients compared with the previous findings. Four patients ultimately underwent surgery, and the postoperative pathological diagnosis was neuroblastoma in three patients and teratoma in one patient. In the nonneonatal group, there were 18 cases of benign tumors, including 9 cases of ganglioneuroma, 2 cases of adrenocortical adenoma, 2 cases of adrenal cyst, 2 cases of teratoma, 1 case of pheochromocytoma, 1 case of nerve sheath tumor, and 1 case of adrenal hemorrhage; and 20 cases of malignant tumors, including 10 cases of neuroblastoma, 9 cases of ganglioneuroblastoma, and 1 case of adrenocortical carcinoma. CONCLUSIONS: Neuroblastoma is the most common type of nonneonatal AI, and detailed laboratory investigations and imaging studies are recommended for aggressive evaluation and treatment in this population. The rate of spontaneous regression of AI is high in neonates, and close observation is feasible if the tumor is small, confined to the adrenal gland and has no distant metastasis.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales , Neuroblastoma , Teratoma , Humanos , Recién Nacido , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Neoplasias de las Glándulas Suprarrenales/terapia , Neoplasias de las Glándulas Suprarrenales/patología , Neuroblastoma/diagnóstico , Neuroblastoma/terapia , Estudios Retrospectivos , Teratoma/diagnóstico , Teratoma/cirugía
5.
Psychol Res ; 88(3): 880-891, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38282131

RESUMEN

Verbal praise is often used to improve prospective memory performance in daily life. According to the motivation cognitive model, the promotional effect of verbal praise on prospective memory may depend largely on redeploying attentional resources, so its promotional effect is likely to be influenced by attention. Two groups of college students (n = 128, n = 117) participated in two experimental studies that examined this hypothesis. Experiment 1 manipulated attention load by changing the difficulty of the ongoing tasks to focus on the effect of verbal praise on prospective memory under different attention load conditions. The results showed that verbal praise promoted prospective memory performance under both attentional load conditions (low, high), but verbal praise mainly promoted the prospective component when the attentional load was low, meanwhile, verbal praise mainly promoted the retrospective component when the attention load was high. Experiment 2 altered the dependence of prospective memory tasks on attentional resources by manipulating the cue focality, further exploring the promotional effect of verbal praise on prospective memory with different types of cues under the low attention load condition. The results showed that verbal praise only promoted prospective memory when non-focal cues were used. The results of this study partially verified the motivation cognitive model.


Asunto(s)
Memoria Episódica , Humanos , Estudios Retrospectivos , Señales (Psicología) , Atención , Cognición
6.
Int J Mol Sci ; 25(5)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38474046

RESUMEN

Post-translational modification of proteins plays a critical role in plant-pathogen interactions. Here, we demonstrate in Nicotiana benthamiana that knockout of NbHAG1 promotes Chinese wheat mosaic virus (CWMV) infection, whereas NbHAG1 overexpression inhibits infection. Transcriptome sequencing indicated that a series of disease resistance-related genes were up-regulated after overexpression of NbHAG1. In addition, cleavage under targets and tagmentation (Cut&Tag)-qPCR results demonstrated that NbHAG1 may activate the transcription of its downstream disease-resistance genes by facilitating the acetylation level of H3K36ac. Therefore, we suggest that NbHAG1 is an important positive regulator of resistance to CWMV infestation.


Asunto(s)
Resistencia a la Enfermedad , Virus de Plantas , Humanos , Virus de Plantas/genética , Procesamiento Proteico-Postraduccional , Enfermedades de las Plantas , Proteínas de Plantas/genética , Regulación de la Expresión Génica de las Plantas
7.
Sensors (Basel) ; 23(14)2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37514790

RESUMEN

Convolutional neural networks (CNNs) have been extensively employed in remote sensing image detection and have exhibited impressive performance over the past few years. However, the abovementioned networks are generally limited by their complex structures, which make them difficult to deploy with power-sensitive and resource-constrained remote sensing edge devices. To tackle this problem, this study proposes a lightweight remote sensing detection network suitable for edge devices and an energy-efficient CNN accelerator based on field-programmable gate arrays (FPGAs). First, a series of network weight reduction and optimization methods are proposed to reduce the size of the network and the difficulty of hardware deployment. Second, a high-energy-efficiency CNN accelerator is developed. The accelerator employs a reconfigurable and efficient convolutional processing engine to perform CNN computations, and hardware optimization was performed for the proposed network structure. The experimental results obtained with the Xilinx ZYNQ Z7020 show that the network achieved higher accuracy with a smaller size, and the CNN accelerator for the proposed network exhibited a throughput of 29.53 GOPS and power consumption of only 2.98 W while consuming only 113 DSPs. In comparison with relevant work, DSP efficiency at an identical level of energy consumption was increased by 1.1-2.5 times, confirming the superiority of the proposed solution and its potential for deployment with remote sensing edge devices.

8.
IEEE Trans Robot ; 39(2): 1637-1652, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37035529

RESUMEN

This paper presents the development of an exoskeleton glove system for people who suffer from brachial plexus injuries, aiming to assist their lost grasping functionality. The robotic system consists of a portable glove system and an embedded controller. The glove system consists of Linear Series Elastic Actuators (LSEA), Rotary Series Elastic Actuators (RSEA), and optimized finger linkages to provide imitated human motion to each finger and a coupled motion of the hand. The design principles and optimization strategies were investigated to balance functionality, portability, and stability. The model-based force control strategy compensated with a backlash model and model-free force control strategy are presented and compared. Results show that our proposed model-free control method achieves the goal of accurate force control. Finally, experiments were conducted with the prototype of the developed integrated exoskeleton glove system. Results from 3 subjects with 150 trials show that our proposed exoskeleton glove system has the potential to be used as a rehabilitation device for patients.

9.
Nano Lett ; 22(1): 229-237, 2022 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-34928162

RESUMEN

Oxidative stress induced by hyperglycemia or chronic inflammation can limit diabetic wound healing, resulting in diabetic foot ulcers. Hydrogen has the potential to act as an antioxidant and scavenge reactive oxygen species, thereby attenuating inflammation in these chronic wounds. However, most of the reported H2 delivery systems for wound healing, including hydrogen gas, hydrogen-rich water, and hydrogen-rich saline, are very short-lived for the low solubility of hydrogen gas. Here, we introduce a hydrogen-producing hydrogel made of living Chlorella and bacteria within a cell-impermeable casing that can continuously produce hydrogen for 60 h. This microbe-hydrogel system can selectively reduce highly toxic •OH and ONOO- species and reduce inflammation. Additional experiments indicated that the microbe-hydrogel dressing could promote cell proliferation and diabetic wound healing by almost 50% at day 3. The symbiotic algae-bacteria hydrogel has excellent biocompatibility and reactive oxygen species scavenging features, indicating it has great promise for clinical use.


Asunto(s)
Chlorella , Diabetes Mellitus , Pie Diabético , Bacterias , Vendajes , Pie Diabético/terapia , Hidrogeles/farmacología , Hidrogeles/uso terapéutico , Hidrógeno/farmacología , Hidrógeno/uso terapéutico , Cicatrización de Heridas
10.
Int J Mol Sci ; 24(22)2023 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-38003668

RESUMEN

The ATP-binding cassette (ABC) superfamily of proteins is a group of evolutionarily conserved proteins. The ABCF subfamily is involved in ribosomal synthesis, antibiotic resistance, and transcriptional regulation. However, few studies have investigated the role of ABCF in wheat (Triticum aestivum) immunity. Here, we identified 18 TaABCFs and classified them into four categories based on their domain characteristics. Functional similarity between Arabidopsis and wheat ABCF genes was predicted using phylogenetic analysis. A comprehensive genome-wide analysis of gene structure, protein motifs, chromosomal location, and cis-acting elements was also performed. Tissue-specific analysis and expression profiling under temperature, hormonal, and viral stresses were performed using real-time quantitative reverse transcription polymerase chain reaction after randomly selecting one gene from each group. The results revealed that all TaABCF genes had the highest expression at 25 °C and responded to methyl jasmonate induction. Notably, TaABCF2 was highly expressed in all tissues except the roots, and silencing it significantly increased the accumulation of Chinese wheat mosaic virus or wheat yellow mosaic virus in wheat leaves. These results indicated that TaABCF may function in response to viral infection, laying the foundation for further studies on the mechanisms of this protein family in plant defence.


Asunto(s)
Genoma de Planta , Triticum , Triticum/metabolismo , Filogenia , Familia de Multigenes , Secuencias Reguladoras de Ácidos Nucleicos , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrés Fisiológico/genética , Perfilación de la Expresión Génica/métodos
11.
J Adv Nurs ; 78(5): 1377-1388, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34636437

RESUMEN

AIMS: To understand how survivors of stroke perceive secondary prevention and explore their perceived barriers and facilitators using the Theoretical Domains Framework. DESIGN: A qualitative descriptive study. METHODS: Nineteen survivors of stroke from three hospitals were recruited and interviewed from April 2019 to April 2020. The data were analysed deductively and inductively by content analysis strategies. RESULTS: Three main themes of perception of secondary prevention were identified, these being active treatment-seeking, attention to taking medications and negative attitude towards lifestyle changes. Using deductive analysis, eight domains of the Theoretical Domains Framework were reported to be relevant in the secondary prevention behaviour of survivors of stroke that mapped to five 'barrier' domains (i.e. knowledge, physical skills, beliefs about capability, beliefs about consequences and optimism) as well as six 'facilitator' domains (i.e. knowledge, interpersonal skills, beliefs about capability, intention, emotion and social influences). Using inductive analysis we identified two additional important factors not falling in the domains of the Theoretical Domains Framework. These comprised female spouses' support and patients' economic autonomy, both of which could be classified as a facilitator or barrier. CONCLUSION: Survivors of stroke perceive seeking treatment and using preventive medication as more important than modifying lifestyle behaviours. Knowledge and insight into the barriers and facilitators of secondary prevention in this specific context provides a theoretical and practical basis for the design of future secondary prevention interventions. IMPACT: Stroke survivors' perceptions of secondary prevention, barriers and facilitators were explored in the context of a developing country. These findings highlight the need to better communicate the importance of improving lifestyle modification and medication adherence, and provide evidence for designing relevant interventions for stroke management in the community.


Asunto(s)
Accidente Cerebrovascular , Sobrevivientes , Femenino , Humanos , Cumplimiento de la Medicación/psicología , Investigación Cualitativa , Prevención Secundaria , Accidente Cerebrovascular/psicología , Sobrevivientes/psicología
12.
J Nurs Manag ; 30(7): 3322-3329, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36017688

RESUMEN

AIM: This study aimed to explore the mediating effects of adversity quotient and the moderating effect of self-efficacy on the relationship between the organizational climate and the work engagement of intensive care unit nurses. BACKGROUND: A good organizational climate can contribute to a high level of work engagement. Adversity quotient and self-efficacy are the key factors affecting nurses' work engagement, while the mechanism of these factors in the organizational climate and work engagement remains unclear. This study was conducted to contribute to the relevant field research. METHODS: The study used a cross-sectional research design and surveyed 323 intensive care unit nurses working in a public hospital in China. The data were analysed using descriptive statistical methods: Pearson correlation analysis and PROCESS macro Model 7 in the regression analysis. RESULTS: Organizational climate was positively correlated with work engagement and adversity quotient. The indirect effect of organizational climate on work engagement through adversity quotient was positive. Furthermore, self-efficacy moderated the relationship between the two factors. CONCLUSION: Cultivating organizational climate and adversity quotients is an important strategy to improve the work engagement of intensive care unit nurses, particularly for nurses with high self-efficacy. IMPLICATIONS FOR NURSING MANAGEMENT: Administrators should make efforts to create a good organizational climate and cultivate nurses' adversity quotients and self-efficacy to decrease their intent to leave.


Asunto(s)
Enfermeras y Enfermeros , Personal de Enfermería en Hospital , Humanos , Compromiso Laboral , Autoeficacia , Estudios Transversales , Encuestas y Cuestionarios , Unidades de Cuidados Intensivos , Cultura Organizacional , Satisfacción en el Trabajo
13.
Int J Psychol ; 57(3): 372-376, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34958456

RESUMEN

The practice effect of time-based prospective memory (TBPM) refers to the phenomenon that TBPM task performance can be significantly improved by repetitive behavioural training. However, reminders are a common strategy for people to perform TBPM tasks in daily life. A large amount of evidence shows that reminders can improve TBPM performance when individuals pay less attention to time information. However, the present study was the first to explore whether external reminders might simultaneously impede the practice effect of TBPM. In this study, 81 undergraduate students were randomly assigned to control group (N = 27, Mage  = 20.00, SDage  = 1.04), reminder group (N = 26, Mage  = 20.35, SDage  = 1.70) and non-reminder group (N = 28, Mage  = 20.25, SDage  = 1.17). In the training stage, the reminder group could receive effective external reminders, while the non-reminder group could not. The results of the training stage revealed that compared with the non-reminder group, the reminder group had fewer time monitoring times and better TBPM performance. In the testing stage, when reminders were removed from the reminder group, we found that compared with the control group without TBPM training, the TBPM performance of the reminder group failed to improve, while that of the non-reminder group improved significantly. Meanwhile, the time estimation ability of the reminder group was not as improved as that of the non-reminder group.


Asunto(s)
Memoria Episódica , Adulto , Cognición , Humanos , Lactante , Adulto Joven
14.
Mechatronics (Oxf) ; 832022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35241876

RESUMEN

This paper proposes a novel human machine interface (HMI) and electronics system design to control a rehabilitation robotic exoskeleton glove. Such system can be activated with biometric authentication using the user's voice, take voice commands as input, recognize the command and perform biometric authentication in real-time with limited computing power, and execute the command on the exoskeleton. The electronics design is a stand-alone plug-and-play modulated design independent of the exoskeleton design. This personalized voice activated grasping system achieves better wearability, lower latency, and improved security than any existing exoskeleton glove control system.

15.
Small ; 17(18): e2007734, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33738929

RESUMEN

The production of oxygen by photosynthetic microorganisms (PSMs) has recently attracted interest concerning the in vivo treatment of multiple diseases for their photosynthetic oxygen production in vivo, since PSMs have good biological safety. Here, the first evidence that PSMs can be used as a photothermal source to perform biophotothermal therapy (bio-PTT) is provided. In vitro and in vivo experiments proved that PSMs can generate heat for the direct elimination of tumors and release a series of pathogen-associated molecular patterns and adjuvants for immune stimulation under light irradiation. Bio-PTT enabled a local tumor inhibition rate exceeding 90% and an abscopal tumor inhibition rate exceeding 75%. This strategy also produced a stronger antitumor immune memory effect to prevent tumor recurrence. The bio-PTT strategy provides a novel direction for photothermal therapy as it simultaneously produces local and abscopal antitumor effects.


Asunto(s)
Hipertermia Inducida , Neoplasias , Línea Celular Tumoral , Humanos , Inmunidad , Inmunoterapia , Neoplasias/terapia , Fototerapia
16.
J Org Chem ; 86(8): 5651-5659, 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33793239

RESUMEN

The formation of isocyanurates via cyclotrimerization of aromatic isocyanates is widely used to enhance the physical properties of a variety of polyurethanes. The most commonly used catalysts in industries are carboxylates for which the exact catalytically active species have remained controversial. We investigated how acetate and other carboxylates react with aromatic isocyanates in a stepwise manner and identified that the carboxylates are only precatalysts in the reaction. The reaction of carboxylates with an excess of aromatic isocyanates leads to irreversible formation of corresponding deprotonated amide species that are strongly nucleophilic and basic. As a result, they are active catalysts during the nucleophilic anionic trimerization, but can also deprotonate urethane and urea species present, which in turn catalyze the isocyanurate formation. The current study also shows how quantum chemical calculations can be used to direct spectroscopic identification of reactive intermediates formed during the active catalytic cycle with predictive accuracy.

17.
Health Expect ; 24(6): 1962-1970, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34363288

RESUMEN

BACKGROUND: Among stroke survivors, the risk of stroke recurrence is high, and stroke survivors' perception of the risk of recurrence is crucial to promote healthy behaviours. OBJECTIVES: This study aimed to explore the perceptions of stroke survivors about their risk of recurrence and healthy behavioural modifications. DESIGN: A qualitative interview study was carried out. RESULTS: We interviewed 19 stroke survivors from 3 hospitals. Thematic analysis showed that the perceptions of recurrence risk and healthy behavioural changes differed between first-ever and recurrent stroke survivors. Three themes were generated from the data of first-ever stroke survivors: indifference to and unawareness of the risk of stroke recurrence, the need for professional information support and different awareness of the importance of different healthy behaviours. For first-relapse stroke patients: worry but feel powerlessness towards recurrent event, accurate information is still warranted, regret of unhealthy behaviour patterns. For the survivors suffered two or more times recurrences: perceived severity of recurrences, increased psychological care need, incorrect perceptions of healthy behaviour. DISCUSSION AND CONCLUSION: Stroke survivors with or without recurrence hold different perceptions towards the risk of recurrence and behavioural changes. The need for information related to warning signs, recurrence risk and risk factors remained consistently unmet. The benefits of healthy behaviours could be a double-edged sword for the prevention of stroke recurrence if the survivors fail to understand these accurately. It is strongly recommended that a specific recurrence risk communication tool and related health education plan be explored on the basis of the number of times patients have experienced stroke recurrence to inform secondary prevention of stroke in the future. PATIENT/PUBLIC CONTRIBUTION: The patients were involved in the formulation of interview questions and conduct of this study. No public was involved in this study.


Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Investigación Cualitativa , Factores de Riesgo , Prevención Secundaria , Sobrevivientes
18.
IEEE Sens J ; 21(19): 21120-21130, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35422676

RESUMEN

The working principle of a SEA is based on using an elastic material connected serially to the mechanical power source to simulate the dynamic behavior of a human muscle. Due to weight and size limitations of a wearable robotic exoskeleton, the hardware design of the SEA is limited. Compact and lightweight SEAs usually have noisy signal output, and can easily be deformed. This paper uses a compact lightweight SEA designed for exoskeleton gloves to demonstrate immeasurable strain and friction force which can cause an average of 34.31% and maximum of 44.7% difference in force measurement on such SEAs. This paper proposes two data driven machine learning methods to accurately calibrate and control SEAs. The multi-layer perception (MLP) method can reduce the average force measurement error to 10.18% and maximum error to 29.13%. The surface fitting method (SF) method can reduce the average force measurement error to 8.06% and maximum error to 35.72%. In control experiments, the weighted MLP method achieves an average of 0.21N force control difference, and the SF method achieves an average of 0.29N force control difference on the finger tips of the exoskeleton glove.

19.
Sensors (Basel) ; 21(23)2021 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-34883953

RESUMEN

Attention mechanisms have demonstrated great potential in improving the performance of deep convolutional neural networks (CNNs). However, many existing methods dedicate to developing channel or spatial attention modules for CNNs with lots of parameters, and complex attention modules inevitably affect the performance of CNNs. During our experiments of embedding Convolutional Block Attention Module (CBAM) in light-weight model YOLOv5s, CBAM does influence the speed and increase model complexity while reduce the average precision, but Squeeze-and-Excitation (SE) has a positive impact in the model as part of CBAM. To replace the spatial attention module in CBAM and offer a suitable scheme of channel and spatial attention modules, this paper proposes one Spatio-temporal Sharpening Attention Mechanism (SSAM), which sequentially infers intermediate maps along channel attention module and Sharpening Spatial Attention (SSA) module. By introducing sharpening filter in spatial attention module, we propose SSA module with low complexity. We try to find a scheme to combine our SSA module with SE module or Efficient Channel Attention (ECA) module and show best improvement in models such as YOLOv5s and YOLOv3-tiny. Therefore, we perform various replacement experiments and offer one best scheme that is to embed channel attention modules in backbone and neck of the model and integrate SSAM into YOLO head. We verify the positive effect of our SSAM on two general object detection datasets VOC2012 and MS COCO2017. One for obtaining a suitable scheme and the other for proving the versatility of our method in complex scenes. Experimental results on the two datasets show obvious promotion in terms of average precision and detection performance, which demonstrates the usefulness of our SSAM in light-weight YOLO models. Furthermore, visualization results also show the advantage of enhancing positioning ability with our SSAM.


Asunto(s)
Redes Neurales de la Computación , Proyectos de Investigación
20.
Zhonghua Nan Ke Xue ; 27(2): 134-139, 2021 Feb.
Artículo en Zh | MEDLINE | ID: mdl-34914329

RESUMEN

OBJECTIVE: To explore the application value of staged urethroplasty by tubularization of the reconstructed urethral plate using the preputial island flap in the treatment of severe hypospadias. METHODS: From May 2014 to February 2019, 91 children with severe hypospadias received one- or two-stage urethroplasty by tubularization of the reconstructed urethral plate with the preputial island flap. We compared the patients' age, glans diameter, length of the straightened urethral defect, and incidence rates of postoperative urethral fistula, urethral diverticulum, glans dehiscence and urethral stricture between the two groups of patients. RESULTS: The 56 patients in the one-stage group were aged 7-144 (21.92 ± 13.37) months old, the urethral defect 3-5 (3.565 ± 0.528) cm in length and the glans 1.0-1.4 (1.195 ± 0.083) cm in diameter, and the 35 in the two-stage group aged 7 -153 (24.78 ± 13.59) months, the urethral defect 3-5 (3.857 ± 0.696) cm in length and the glans 0.8-2.5 (1.206 ± 0.389) cm in diameter. There were no statistically significant differences in age, glans diameter and the length of urethral defect between the two groups. In the one-stage group were found 18 cases of postoperative urinary fistula, 1 case of glans dehiscence, 1 case of urethral diverticulum, and 1 case of both urethral diverticulum and glans dehiscence, all cured by repeated urinary fistula repair/urethroplasty. No urinary fistula occurred in the two-stage group postoperatively except 4 cases of glans dehiscence, of which 2 were cured by repeated repair and the other 2 refused reoperation. The success rate was significantly higher in the two-stage than in the one-stage urethroplasty group (88.57% vs 62.50%, P < 0.05). CONCLUSIONS: Two-stage urethroplasty by tubularization of the reconstructed urethral plate with the preputial island flap can significantly reduce the incidence of urethral fistula in patients with severe hypospadias, but may increase the number of operations in those who do not need staged surgery. The necessity of two-stage urethroplasty can be determined according to the development of the glans, the degree of penile curvature, and the length of urethra defect.


Asunto(s)
Hipospadias , Fístula Urinaria , Preescolar , Humanos , Hipospadias/cirugía , Lactante , Masculino , Pene , Colgajos Quirúrgicos , Uretra/cirugía , Fístula Urinaria/etiología , Fístula Urinaria/cirugía
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