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1.
Wound Repair Regen ; 32(2): 146-154, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38129180

RESUMO

Hyperbaric oxygen therapy (HBOT) has been used as an adjuvant treatment for crush injury because it can improve tissue hypoxia and stimulate wound healing. However, the actual role of HBOT in crush hand injury is still unknown. This study is to assess the efficacy of HBOT for crush hand patients, as well as the impact of HBOT initiation timing. Between 2018 and 2021, 72 patients with crush hand injury were retrospectively reviewed. The patients were divided into the HBOT and control group, and each group had 36 patients. The average session of HBOT was 18.2 (5-32 sessions) per patient, and no patient had a complication related to the treatment. The two groups had similar demographics, but HBOT group had larger injured area (73.6 ± 51.0 vs. 48.2 ± 45.5 cm2 , p = 0.03). To better control the confounding factors, we performed the subgroup analysis with cut-off injured area of 50 cm2 . In the patients with smaller injured area (≦50 cm2 ), the HBOT group had shorter wound healing time (29.9 ± 12.9 vs. 41.0 ± 18.9 days, p = 0.03). The early HBOT group (first session ≤72 h post-operatively) had shorter hospital stay (8.1 ± 6.4 vs. 15.5 ± 11.4 days, p = 0.04), faster wound healing (28.7 ± 17.8 vs. 41.1 ± 18.1 days, p = 0.08) and less operations (1.54 ± 0.78 vs. 2.41 ± 1.62, p = 0.06) although the latter two didn't achieve statistical significance. HBOT is safe and effective in improving wound healing of hand crush injury. Early intervention of HBOT may be more beneficial. Future research is required to provide more evidence.


Assuntos
Lesões por Esmagamento , Traumatismos da Mão , Oxigenoterapia Hiperbárica , Humanos , Cicatrização , Estudos Retrospectivos , Traumatismos da Mão/terapia , Lesões por Esmagamento/terapia
2.
Epilepsy Behav ; 152: 109667, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38301456

RESUMO

PURPOSE: It has become evident that patients with epilepsy require strong self-efficacy support in various domains, including work, social interaction, and academic performance, to ensure their complete social functioning. Nevertheless, previous studies have predominantly assessed the self-efficacy of individuals with epilepsy from a singular perspective of disease management. This study aimed to develop the Multidimensional Self-Efficacy Scale for Epilepsy (MSESE) to assess multiple dimensions and establish its psychometric properties. METHODS: We compiled a total of 25 questions for the initial version of the questionnaire based on a review of the literature and insights from experts, patients, and family members. The study included 180 adult patients with epilepsy who met the research criteria, with 126 of them serving as pre-test samples. All participants completed the MSESE, Brief Symptom Rating Scale-50 (BSRS-50), Rosenberg Self-Esteem Scale-Chinese version (RSES-C), and General Self-Efficacy Scale (GSES). RESULTS: The final scale consisted of 12 items across four dimensions, with item factor loadings ranging from .51 to .90. Most of the fit indices indicated a good fit. Construct validity was established through significant correlations with the BSRS-50, RSES-C, and GSES (r = -0.51 to 0.69, p < 0.01). Internal consistency coefficients for the MSESE were strong at .90, with individual dimensions ranging from 0.71 to 0.89. The MSESE also demonstrated a satisfactory test-retest reliability of 0.72. CONCLUSIONS: The MSESE is a convenient, multidimensional, and easy-to-use scale with good psychometric properties, making it suitable for both clinical assessments and research purposes.


Assuntos
Epilepsia , Autoeficácia , Adulto , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
3.
Arch Toxicol ; 98(5): 1543-1560, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38424264

RESUMO

Excavatolide C (EXCC), a marine coral-derived compound, exhibits an antiproliferation effect on bladder cancer cells. The present study evaluated the improvement in the antiproliferation ability of EXCC by co-treatment with cisplatin in bladder cancer cells. EXCC/cisplatin (12.5 and 1 µg/mL) showed higher antiproliferation effects on bladder cancer cells than single treatments (EXCC or cisplatin alone) in the 48 h ATP assay. EXCC/cisplatin also enhanced the increase in subG1, annexin V-mediated apoptosis, and activation of poly (ADP-ribose) polymerase (PARP) and several caspases (caspases 3, 8, and 9) compared to the single treatments. Cellular and mitochondrial oxidative stress was enhanced with EXCC/cisplatin compared to the single treatments according to analyses of reactive oxygen species (ROS), mitochondrial superoxide, and mitochondrial membrane potential; in addition, cellular antioxidants, such as glutathione (GSH), and the mRNA expressions of antioxidant signaling genes (catalase and NFE2-like bZIP transcription factor 2) were downregulated. EXCC/cisplatin treatment produced more DNA damage than the single treatments, as indicated by γH2AX and 8-hydroxy-2'-deoxyguanosine levels. Moreover, several DNA repair genes for homologous recombination (HR) and non-homologous end joining (NHEJ) were downregulated in EXCC/cisplatin compared to others. The addition of the GSH precursor N-acetylcysteine, which has ROS scavenging activity, attenuated all EXCC/cisplatin-induced changes. Notably, EXCC/cisplatin showed lower antiproliferation, apoptosis, ROS induction, GSH depletion, and γH2AX DNA damage in normal cells than in bladder cancer cells. Therefore, the co-treatment of EXCC/cisplatin reduces the proliferation of bladder cancer cells via oxidative stress-mediated mechanisms with normal cell safety.


Assuntos
Cisplatino , Neoplasias da Bexiga Urinária , Humanos , Espécies Reativas de Oxigênio/metabolismo , Cisplatino/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Apoptose , Antioxidantes/farmacologia , Dano ao DNA , Caspases/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Poli(ADP-Ribose) Polimerases/farmacologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética
4.
Int Arch Occup Environ Health ; 97(4): 401-412, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38480609

RESUMO

OBJECTIVE: This study investigates the associations of α1-antitrypsin, inter-α-trypsin inhibitor heavy chain (ITIH4), and 8-isoprostane with lung function in shipyard workers exposed to occupational metal fume fine particulate matter (PM2.5), which is known to be associated with adverse respiratory outcomes. METHODS: A 3-year follow-up study was conducted on 180 shipyard workers with 262 measurements. Personal exposure to welding fume PM2.5 was collected for an 8-h working day. Pre-exposure, post-exposure, and delta (∆) levels of α1-antitrypsin, ITIH4, and 8-isoprostane were determined in urine using enzyme-linked immunosorbent assays. Post-exposure urinary metals were sampled at the beginning of the next working day and analyzed by inductively coupled plasma-mass spectrometry. Lung function measurements were also conducted the next working day for post-exposure. RESULTS: An IQR increase in PM2.5 was associated with decreases of 2.157% in FEV1, 2.806% in PEF, 4.328% in FEF25%, 5.047% in FEF50%, and 7.205% in FEF75%. An IQR increase in PM2.5 led to increases of 42.155 µg/g in ∆α1-antitrypsin and 16.273 µg/g in ∆ITIH4. Notably, IQR increases in various urinary metals were associated with increases in specific biomarkers, such as post-urinary α1-antitrypsin and ITIH4. Moreover, increases in ∆ α1-antitrypsin and ∆ITIH4 were associated with decreases in FEV1/FVC by 0.008% and 0.020%, respectively, and an increase in ∆8-isoprostane resulted in a 1.538% decline in FVC. CONCLUSION: Our study suggests that urinary α1-antitrypsin and ITIH4 could indicate early lung function decline in shipyard workers exposed to metal fume PM2.5, underscoring the need for better safety and health monitoring to reduce respiratory risks.


Assuntos
Exposição Ocupacional , Soldagem , Humanos , Seguimentos , Estudos Prospectivos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Metais , Material Particulado/análise , Pulmão , Biomarcadores/urina
5.
Surg Today ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842555

RESUMO

PURPOSE: To evaluate the influence of intraoperative neuromonitoring (IONM) on vocal cord palsy (VCP) rates and assess the temporal trends in VCP rates. METHODS: The subjects of this retrospective study were patients who underwent thyroidectomy for thyroid cancer between March, 2014 and June, 2022, at a university hospital in Korea. We compared VCP rates between the non-IONM and IONM groups and analyzed the risk factors for VCP and VCP rates over time. RESULTS: A total of 712 patients were included in the analysis. The rates of transient and permanent VCP did not differ significantly between the non-IONM and IONM groups. Transient VCP occurred in 4.6% and 4.3% patients (p = 0.878) and VCP was permanent in 0.7% and 0.4% patients (p = 0.607) in the non-IONM and IONM groups, respectively. Among the nerves at risk, transient damage occurred in 2.8% and 3.0% patients (p = 0.901), and permanent damage occurred in 0.4% and 0.3% (p = 0.688), respectively. Multivariate analysis revealed no significant risk factors for VCP. There was a significant decreasing trend in VCP rates over time as the cumulative number of cases increased (p = 0.017). CONCLUSIONS: IONM did not reduce the risk of VCP significantly. However, the declining trend of VCP rates suggests that the surgeon's experience may mitigate VCP risk.

6.
Am J Otolaryngol ; 45(5): 104420, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39067090

RESUMO

BACKGROUND: Head and neck surgical simulation training (SST) is an important part in otolaryngology head and neck surgical education. In this study, we provide a live porcine model for SST in recurrent laryngeal nerve (RLN) and facial nerve (FN) dissection for otolaryngology head and neck residents. METHODS: A lecture with surgical manual is provided to illustrate the surgical landmarks of pig, and step-by-step procedures for thyroid and parotid surgery, as well as neck dissection. We used 4-month-old pig weighting 32 kg for the SST. The mentor demonstrated result of RLN injury with continuous nerve monitoring. Participants used monopolar stimulation probe (4 pulse/s, 100 µs, 3-8 mA; Medtronic) to identify and intermittent monitor the RLN and FN during the SST. After the dissection course, we conducted a questionnaire survey to check the effectiveness of this training model. RESULTS: Total 30 participants were recruited, including 16 female and 14 male resident doctors. There were 1, 4 and 25 learners for 3rd year, 4th and 5th years residents, respectively. Before this training course, 53 % (16/30) and 63 % (19/30) had successful experience in finding the RLN and FN, respectively. After the SST, all of our participants had successful identify the RLN and FN (p-value <0.01); all had positive response to stimulation and familiar with the procedure. CONCLUSIONS: The live porcine model is effectiveness in SST for RLN and FN dissection. Live porcine model with real-time RLN and FN monitoring should be provided for otolaryngology head and neck resident training.


Assuntos
Nervo Facial , Internato e Residência , Otolaringologia , Nervo Laríngeo Recorrente , Treinamento por Simulação , Animais , Suínos , Treinamento por Simulação/métodos , Otolaringologia/educação , Internato e Residência/métodos , Nervo Facial/cirurgia , Feminino , Humanos , Masculino , Nervo Laríngeo Recorrente/cirurgia , Dissecação/educação , Modelos Animais , Competência Clínica , Traumatismos do Nervo Laríngeo Recorrente/prevenção & controle , Esvaziamento Cervical/educação
7.
Med Teach ; : 1-7, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38379399

RESUMO

BACKGROUND: There are limited studies that explored the preparation and challenges faced by standardized patients (SPs) in portraying characters in difficult communication scenarios, and the strategies used to overcome these challenges. The purpose of this study was to understand the experience of SPs in interpreting difficult communication situations and the learning needs of performing similar scenarios. And it allows the researchers to explore the meaning, beliefs, values, and aspiration associated with their role as SPs. The findings could shade light on the significance of their experiences and provide valuable insights for the development of future SP training programs. METHODS: The design of this study is framed by a narrative inquiry, using semi-structured guidelines to conduct in-depth interviews with 11 SPs who have participated in the performances of difficult communication situations. Research data were analyzed by Polkinghorne narrative analysis, and Riessman's four criteria were used to establish rigor. RESULTS: Analysis revealed the following five themes: scenarios to real life connections, process of preparing for a performance, methods to detach from character, obtaining unexpected rewards, and needs for performance training. There are two to three subthemes that are subsumed under each theme. CONCLUSIONS: To strengthen training in difficult communication for healthcare professionals, the use of SPs to interpret challenging difficult communication scenarios will continue to increase. Educators need to ensure that SPs are fully prepared physically and emotionally before, during and after their performance. Offering of continuing education and training in feedback techniques are crucial to extend the tenure of SPs, reduce their frustration, prevent attrition, and ultimately, reduce training costs. In the future, SP training should also include detachment and feedback techniques to alleviate SPs' stress.

8.
J Formos Med Assoc ; 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38296697

RESUMO

BACKGROUND: Primary breast diffuse large B-cell lymphoma (PB-DLBCL) is rare, with a high incidence of central nervous system (CNS) relapse. This study aims to investigate clinical characteristics, prognostic factors, and outcomes in Taiwanese PB-DLBCL patients and review the literature on PB-DLBCL. METHODS: Thirty-one PB-DLBCL patients diagnosed between 2000 and 2021 were retrospectively enrolled for analysis. RESULTS: The median age was 49 (range 26-79) years. The complete remission (CR) rate was 90.3%. Nine (90%) of the ten patients who experienced relapse had CNS involvement at the time of relapse. The one-year, two-year, and five-year progression-free survival (PFS) rates were 86.6% (95% confidence interval [CI] 75.2-99.8), 75.8% (95% CI 61.6-93.2), and 45.1% (95% CI 29.5-68.9), respectively. The five-year overall survival (OS) rate was 64.1% (95 % CI 48.4-85.0). A stage-modified International Prognostic Index (mIPI) less than two (five-year PFS rate 52.5% vs. 17.1%, P = 0.02) and the achievement of CR after first-line treatment (two-year PFS rate 80.3% vs. 33.3%, P < 0.001) were significant favorable prognostic factors for PFS. Hematopoietic stem cell transplantation (HSCT) after the first relapse was associated with significantly improved post-relapse OS (five-year OS rate 85.7% vs. 20.0%, P = 0.02) and PFS (five-year PFS rate 85.7% vs. 20.0%, P = 0.02). CONCLUSION: Patients with low-risk mIPI scores, CR after first-line treatment, and those who underwent HSCT after the first relapse had significantly better survival. Intrathecal chemotherapy conferred no benefit in preventing CNS relapse. Further research is needed to assess frontline HSCT's effectiveness in improving outcomes and preventing CNS relapses in PB-DLBCL patients.

9.
J Formos Med Assoc ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360489

RESUMO

BACKGROUND: Endovascular thrombectomy (EVT) is a time-sensitive treatment for acute ischemic stroke with large vessel occlusion. To optimize transfer efficiency, a web-based platform was introduced in the Tainan Stroke Network (TSN). We assessed its application and effectiveness in regional stroke care. METHOD: This new web-based platform containing a questionnaire-style interface was introduced on October 1, 2021. To assess the transfer efficiency and patient outcomes, acute stroke patients transferred from PSCs to CSC for EVT from April 01, 2020, to December 30, 2022, were enrolled. The patients were classified into the traditional transferal pathway (TTP) group and the new transferal pathway (NTP) group depending on mode of transfer. Patient characteristics, time segments after stroke onset and outcome were compared between groups. RESULT: A total of 104 patients were enrolled, with 77 in the TTP group and 27 in the NTP group. Compared to the TTP group, the NTP group had a significantly shorter onset-to-CSC door time (TTP vs. NTP: 267 vs. 198 min; p = 0.041) and a higher EVT rate (TTP vs. NTP: 18.2% vs. 48.1%, p = 0.002). Among EVT patients, those in the NTP group had a significantly shorter CSC door-to-puncture time (TTP vs. NTP: 131.5 vs. 110 min; p = 0.029). The NTP group had a higher rate of good functional outcomes at 3 months (TTP vs. NTP: 21% vs. 61.5%; p = 0.034). CONCLUSION: This new web-based EVT transfer system provides notable improvements in clinical outcomes, transfer efficiency, and EVT execution for potential EVT candidates without markedly changing the regional stroke care paradigm.

10.
Medicina (Kaunas) ; 60(3)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38541096

RESUMO

Background and Objective: Existing evidence indicates the potential benefits of electroencephalography neurofeedback (NFB) training for cognitive function. This study aims to comprehensively review all available evidence investigating the effectiveness of NFB on working memory (WM) and episodic memory (EM) in the elderly population. Material and Methods: A systematic search was conducted across five databases to identify clinical trials examining the impact of NFB on memory function in healthy elderly individuals or those with mild cognitive impairment (MCI). The co-primary outcomes focused on changes in WM and EM. Data synthesis was performed using a random-effects meta-analysis. Results: Fourteen clinical trials (n = 284) were included in the analysis. The findings revealed that NFB was associated with improved WM (k = 11, reported as Hedges' g = 0.665, 95% confidence [CI] = 0.473 to 0.858, p < 0.001) and EM (k = 12, 0.595, 0.333 to 0.856, p < 0.001) in the elderly, with moderate effect sizes. Subgroup analyses demonstrated that NFB had a positive impact on both WM and EM, not only in the healthy population (WM: k = 7, 0.495, 0.213 to 0.778, p = 0.001; EM: k = 6, 0.729, 0.483 to 0.976, p < 0.001) but also in those with MCI (WM: k = 6, 0.812, 0.549 to 1.074, p < 0.001; EM: k = 6, 0.503, 0.088 to 0.919, p = 0.018). Additionally, sufficient training time (totaling more than 300 min) was associated with a significant improvement in WM (k = 6, 0.743, 0.510 to 0.976, p < 0.001) and EM (k = 7, 0.516, 0.156 to 0.876, p = 0.005); however, such benefits were not observed in groups with inadequate training time. Conclusions: The results suggest that NFB is associated with enhancement of both WM and EM in both healthy and MCI elderly individuals, particularly when adequate training time (exceeding 300 min) is provided. These findings underscore the potential of NFB in dementia prevention or rehabilitation.


Assuntos
Disfunção Cognitiva , Memória Episódica , Memória de Curto Prazo , Neurorretroalimentação , Humanos , Neurorretroalimentação/métodos , Memória de Curto Prazo/fisiologia , Idoso , Disfunção Cognitiva/prevenção & controle , Eletroencefalografia/métodos , Feminino , Masculino
11.
Angew Chem Int Ed Engl ; 63(20): e202403017, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38429994

RESUMO

Crafting single-atom catalysts (SACs) that possess "just right" modulated electronic and geometric structures, granting accessible active sites for direct room-temperature benzene oxidation is a coveted objective. However, achieving this goal remains a formidable challenge. Here, we introduce an innovative in situ phosphorus-immitting strategy using a new phosphorus source (phosphorus nitride, P3N5) to construct the phosphorus-rich copper (Cu) SACs, designated as Cu/NPC. These catalysts feature locally protruding metal sites on a nitrogen (N)-phosphorus (P)-carbon (C) support (NPC). Rigorous analyses, including X-ray absorption spectroscopy (XAS) and X-ray photoelectron spectroscopy (XPS), validate the coordinated bonding of nitrogen and phosphorus with atomically dispersed Cu sites on NPC. Crucially, systematic first-principles calculations, coupled with the climbing image nudged-elastic-band (CI-NEB) method, provide a comprehensive understanding of the structure-property-activity relationship of the distorted Cu-N2P2 centers in Cu/NPC for selective oxidation of benzene to phenol production. Interestingly, Cu/NPC has shown more energetically favorable C-H bond activation compared to the benchmark Cu/NC SACs in the direct oxidation of benzene, resulting in outstanding benzene conversion (50.3 %) and phenol selectivity (99.3 %) at room temperature. Furthermore, Cu/NPC achieves a remarkable turnover frequency of 263 h-1 and mass-specific activity of 35.2 mmol g-1 h-1, surpassing the state-of-the-art benzene-to-phenol conversion catalysts to date.

12.
Surg Technol Int ; 432023 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-38237113

RESUMO

INTRODUCTION: Total thyroidectomy is associated with a high rate of transient or permanent hypoparathyroidism. During surgery, indocyanine green (ICG) fluorescein angiography can be used to detect and preserve well-vascularized parathyroid glands. This technique has been introduced as an intraoperative support to prevent postoperative hypoparathyroidism. MATERIAL AND METHODS: One-hundred consecutive patients who had undergone total thyroidectomy were included in this study. Autofluoroscopy was used on the first dominant side of thyroidectomy and to identify the contralateral parathyroid glands. An intravenous bolus of 5 mg ICG (VERDYE, Diagnostic Green GmbH, Aschheim-Dornacht, Germany) was administered once. ICG fluorescein angiography was used as a "bridge" at the end of the first dominant hemithyroidectomy and after exposure of the parathyroid glands on the second side. This allowed us to (i) determine the vascularization of the first two parathyroid glands and (ii) define the blood vessels and thus the line of dissection of the parathyroid glands of the second resection side. Finally, autofluoroscopy was then applied outside the surgical area on the surgical specimen to assess forgotten parathyroid glands, which should therefore be re-implanted. Autofluoroscopy and ICG fluorescein angiography were evaluated in real time using the same technology, i.e., FLUOBEAM® LX (EUROPE - Fluoptics Grenoble, France; USA - Fluoptics Imaging Inc., Cambridge, MA, USA). The study was approved by the local ethics committee. RESULTS: Autofluorescence and ICG fluorescein angiography were performed without any problems in all cases. A total of 370 parathyroid glands were detected in this series. ICG changed the surgical strategy for the first-side parathyroid glands in 5% of cases, i.e,. they were not well-vascularized and were re-implanted. The rate of transient hypoparathyroidism was 19%. The percentage of parathyroids in the surgical specimen was 3.5% and all were re-implanted during the same surgery. There was no case of postoperative definitive hypoparathyroidism when at least one parathyroid gland with a high fluorescence intensity was preserved on the first side of resection. CONCLUSION: Use of ICG fluorescein angiography may contribute to predicting and thus preventing postoperative definitive hypoparathyroidism after total thyroidectomy. The results of this case series confirm recent studies. Caution is advised when weakly perfused parathyroid glands are discovered.

14.
IEEE Trans Cybern ; 54(2): 706-716, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38127618

RESUMO

This article investigates the problem of the fully distributed self-triggered secure synchronization control for multiagent systems (MASs) under communication link denial-of-service (CLDoS) attacks. First, an algorithm for constructing a k -connected graph is designed to reduce the impact of CLDoS attacks on MASs. Based on which, a fully distributed observer-based resilient control scheme is co-designed to reduce the dependence on the communication topology information. In addition, a self-triggered method is proposed to avoid the real-time monitoring of system information, further to reduce the resource consumption. Finally, the effectiveness and superiority of the construction algorithm and resilient control scheme are supported by comparison simulation examples.

15.
Artigo em Inglês | MEDLINE | ID: mdl-38379235

RESUMO

This article designs a new hierarchical distributed data-driven adaptive learning control algorithm to accomplish the leader-following tracking control objective for nonaffine nonlinear multiagent systems (MASs). The proposed hierarchical control structure is composed of a distributed observer and a decentralized data-driven adaptive learning controller. Considering that some followers cannot directly receive information from the leader, a distributed observer is designed to estimate the information of the leader. Based on this, a decentralized data-driven adaptive learning controller is further devised to enable the follower to track the estimated information of the leader, where the model parameter learning algorithm is developed to capture the dynamic characteristics of the original system. One advantage of the developed hierarchical control learning algorithm is that neither the leader's system model nor the follower's system model is needed. The other one is the elimination of the noncausal problem without the additional assumption. Simulation results exemplify the merits of the theoretical results by comparisons.

16.
IEEE Trans Cybern ; PP2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345963

RESUMO

Asymptotic observability of distributed Boolean networks (DBNs) is studied in this article. Via a parallel extension method, asymptotic observability of the original system is converted to reachability at a fixed point of the extended system. Based on the structure matrix of the extended system, a necessary and sufficient condition is presented for asymptotic observability. Further, for unobservable systems, mode-dependent pinning control is first introduced and applied to achieve asymptotic observability, including the selections of pinning nodes, the design of output feedback controls, and the adding approaches. Then, a set of matrices is defined for the construction of the desired structure matrix. Based on it, a necessary condition is given to guarantee the solvability of the corresponding output feedback controls and the adding approaches. Finally, a numerical example is presented to show the effectiveness of the obtained results.

17.
IEEE Trans Cybern ; PP2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39093678

RESUMO

This article intends to study the asynchronous control problem for 2-D Markov jump systems (MJSs) with nonideal transition probabilities (TPs) under the Roesser model. Two practical considerations motivate the current work. First, considering that the system mode cannot always be observed accurately, a hidden Markov model (HMM) is adopted to describe the relationship between the mismatched modes. Second, considering that the TPs information related to the Markov process and the observation process is difficult to obtain, the nonideal TPs (unknown or uncertain) are simultaneously considered on the two processes. Under the considerations, several new sufficient conditions are developed for concerned closed-loop 2-D MJSs with nonideal TPs, by which the asymptotic mean square stability is ensured with an H∞ performance index. A nonconservative separation strategy is utilized to decouple the system mode TPs and the observation TPs to facilitate the analysis of nonideal TPs. An unified LMI-based condition is finally developed for the concerned closed-loop 2-D MJSs with/without nonideal TPs, showing more satisfactory conservatism than that in the literature. In the end, we present two examples to validate the superiority of the proposed design method.

18.
Med Sci Sports Exerc ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767985

RESUMO

INTRODUCTION: The effects of breaking up sitting on gut hormone responses and free-living energy compensatory behaviours are still unclear in people of Asian ethnicity. METHODS: 26 Asians including 13 lean individuals (Lean) and 13 individuals with centrally overweight/obesity (OW), aged between 20 to 45 years, completed a randomized crossover study with either 5.5-h uninterrupted sitting (SIT) or 5.5-h sitting with 2 min walking at 6.4 km/h every 20 min (ACTIVE) in the laboratory. Blood samples were collected at regular time-points to examine postprandial glucagon-like peptide 1 (GLP-1), peptide YY (PYY) and glucose-dependent insulinotropic polypeptide (GIP) concentrations. Free-living physical activity and energy intake were recorded using wearable devices and weighed food diaries outside the laboratory until midnight. Paired t-tests were conducted to compare responses between trials. RESULTS: Postprandial GLP-1 and PYY incremental area under curve values were higher in the ACTIVE trial versus SIT in both Lean and OW groups (all, p < 0.05), but there was no difference in GIP in either group (both, p > 0.05). There were no differences in free-living physical activity (volume and intensity) or energy intake (total and macronutrients) between trials in either group (all, p > 0.05), resulting in greater total physical activity over the 24-h monitoring period in ACTIVE trial versus SIT trial (both, p < 0.05). CONCLUSIONS: Breaking up sitting increases postprandial GLP-1 and PYY concentrations in Asians, but does not induce subsequent behavioural compensation, resulting in greater 24-h physical activity levels and lower relative energy intake, in inactive individuals irrespective of bodyweight status.

19.
Materials (Basel) ; 17(12)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38930368

RESUMO

Stainless steel grade 430 is a type of soft magnetic electromagnetic material with rapid magnetization and demagnetization properties. Considering the delay phenomenon during operation, this study selected 430 stainless steel as the material and explored various metallurgical methods such as magnetic annealing and the addition of Mo as well as increasing the Si content to investigate the microstructure, mechanical behavior, and magnetic properties of each material, aiming to improve the magnetic properties of 430 stainless steel. Experimental results showed that the four electromagnetic steel materials (430F, 430F-MA, 434, and KM31) had equiaxed grain matrix structures, and excellent tensile and elongation properties were observed for each specimen. Additionally, the magnetic properties of the 430F specimen were similar under the DC and AC-10 Hz conditions. According to the hysteresis curves under different AC frequencies (10, 100, 1000 Hz), both magnetic annealing and the addition of Mo could reduce the Bm, Br, and Hc values of the raw 430F material. Increasing the Si content resulted in a decrease in Hc values and an increase in Bm and Br values.

20.
Nat Rev Chem ; 8(6): 471-485, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38698142

RESUMO

High-entropy materials emerged as a field of research in 2004, when the first research on high-entropy alloys was published. The scope was soon expanded from high-entropy alloys to medium-entropy alloys, as well as to ceramics, polymers and composite materials. A fundamental understanding on high-entropy materials was proposed in 2006 by the 'four core effects' - high-entropy, severe-lattice-distortion, sluggish-diffusion and cocktail effects - which are often used to describe and explain the mechanisms of various peculiar phenomena associated with high-entropy materials. Throughout the years, the effects have been examined rigorously, and their validity has been affirmed. This Perspective discusses the fundamental understanding of the four core effects in high-entropy materials and gives further insights to strengthen the understanding for these effects. All these clarifications are believed to be helpful in understanding low-to-high-entropy materials as well as to aid the design of materials when studying new compositions or pursuing their use in applications.

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