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1.
J Med Syst ; 48(1): 31, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488884

RESUMO

Intraoperative cardiopulmonary variables are well-known predictors of postoperative pulmonary complications (PPC), traditionally quantified by median values over the duration of surgery. However, it is unknown whether cardiopulmonary instability, or wider intra-operative variability of the same metrics, is distinctly associated with PPC risk and severity. We leveraged a retrospective cohort of adults (n = 1202) undergoing major non-cardiothoracic surgery. We used multivariable logistic regression to evaluate the association of two outcomes (1)moderate-or-severe PPC and (2)any PPC with two sets of exposure variables- (a)variability of cardiopulmonary metrics (inter-quartile range, IQR) and (b)median intraoperative cardiopulmonary metrics. We compared predictive ability (receiver operating curve analysis, ROC) and parsimony (information criteria) of three models evaluating different aspects of the intra-operative cardiopulmonary metrics: Median-based: Median cardiopulmonary metrics alone, Variability-based: IQR of cardiopulmonary metrics alone, and Combined: Medians and IQR. Models controlled for peri-operative/surgical factors, demographics, and comorbidities. PPC occurred in 400(33%) of patients, and 91(8%) experienced moderate-or-severe PPC. Variability in multiple intra-operative cardiopulmonary metrics was independently associated with risk of moderate-or-severe, but not any, PPC. For moderate-or-severe PPC, the best-fit predictive model was the Variability-based model by both information criteria and ROC analysis (area under the curve, AUCVariability-based = 0.74 vs AUCMedian-based = 0.65, p = 0.0015; AUCVariability-based = 0.74 vs AUCCombined = 0.68, p = 0.012). For any PPC, the Median-based model yielded the best fit by information criteria. Predictive accuracy was marginally but not significantly higher for the Combined model (AUCCombined = 0.661) than for the Median-based (AUCMedian-based = 0.657, p = 0.60) or Variability-based (AUCVariability-based = 0.649, p = 0.29) models. Variability of cardiopulmonary metrics, distinct from median intra-operative values, is an important predictor of moderate-or-severe PPC.


Assuntos
Pulmão , Complicações Pós-Operatórias , Adulto , Humanos , Estudos Retrospectivos , Estudos Prospectivos , Fatores de Risco , Complicações Pós-Operatórias/epidemiologia
2.
J Biol Chem ; 298(3): 101626, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35074425

RESUMO

The bacterial second messenger bis-(3'-5')-cyclic diguanylate monophosphate (c-di-GMP) controls various cellular processes, including motility, toxin production, and biofilm formation. c-di-GMP is enzymatically synthesized by GGDEF domain-containing diguanylate cyclases and degraded by HD-GYP domain-containing phosphodiesterases (PDEs) to 2 GMP or by EAL domain-containing PDE-As to 5'-phosphoguanylyl-(3',5')-guanosine (pGpG). Since excess pGpG feedback inhibits PDE-A activity and thereby can lead to the uncontrolled accumulation of c-di-GMP, a PDE that degrades pGpG to 2 GMP (PDE-B) has been presumed to exist. To date, the only enzyme known to hydrolyze pGpG is oligoribonuclease Orn, which degrades all kinds of oligoribonucleotides. Here, we identified a pGpG-specific PDE, which we named PggH, using biochemical approaches in the gram-negative bacteria Vibrio cholerae. Biochemical experiments revealed that PggH exhibited specific PDE activity only toward pGpG, thus differing from the previously reported Orn. Furthermore, the high-resolution structure of PggH revealed the basis for its PDE activity and narrow substrate specificity. Finally, we propose that PggH could modulate the activities of PDE-As and the intracellular concentration of c-di-GMP, resulting in phenotypic changes including in biofilm formation.


Assuntos
GMP Cíclico/análogos & derivados , Diester Fosfórico Hidrolases , Vibrio cholerae , Proteínas de Bactérias/metabolismo , Biofilmes , GMP Cíclico/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Transdução de Sinais , Especificidade por Substrato , Vibrio cholerae/enzimologia , Vibrio cholerae/metabolismo
3.
Am J Respir Crit Care Med ; 206(3): 260-270, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35550018

RESUMO

Rationale: Constrictive bronchiolitis (ConB) is a relatively rare and understudied form of lung disease whose underlying immunopathology remains incompletely defined. Objectives: Our objectives were to quantify specific pathological features that differentiate ConB from other diseases that affect the small airways and to investigate the underlying immune and inflammatory phenotype present in ConB. Methods: We performed a comparative histomorphometric analysis of small airways in lung biopsy samples collected from 50 soldiers with postdeployment ConB, 8 patients with sporadic ConB, 55 patients with chronic obstructive pulmonary disease, and 25 nondiseased control subjects. We measured immune and inflammatory gene expression in lung tissue using the NanoString nCounter Immunology Panel from six control subjects, six soldiers with ConB, and six patients with sporadic ConB. Measurements and Main Results: Compared with control subjects, we found shared pathological changes in small airways from soldiers with postdeployment ConB and patients with sporadic ConB, including increased thickness of the smooth muscle layer, increased collagen deposition in the subepithelium, and lymphocyte infiltration. Using principal-component analysis, we showed that ConB pathology was clearly separable both from control lungs and from small airway disease associated with chronic obstructive pulmonary disease. NanoString gene expression analysis from lung tissue revealed T-cell activation in both groups of patients with ConB with upregulation of proinflammatory pathways, including cytokine-cytokine receptor interactions, NF-κB (nuclear factor-κB) signaling, TLR (Toll-like receptor) signaling, T-cell receptor signaling, and antigen processing and presentation. Conclusions: These findings indicate shared immunopathology among different forms of ConB and suggest that an ongoing T-helper cell type 1-type adaptive immune response underlies airway wall remodeling in ConB.


Assuntos
Asma , Bronquiolite Obliterante , Doença Pulmonar Obstrutiva Crônica , Remodelação das Vias Aéreas/fisiologia , Humanos , Pulmão , NF-kappa B/metabolismo
4.
J Korean Med Sci ; 38(19): e140, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37191844

RESUMO

BACKGROUND: 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) is known as a lung carcinogen. The objective of this study was to investigate associations of urine NNAL concentrations and smoking status. METHODS: This was a cross-sectionally designed study based on data from the 2016-2018 Korean National Health and Nutrition Examination Survey. A total of 2,845 participants were classified into past-smoker, electronic cigarette (e-cigar) only, dual-user, and cigarette only smoker groups. All sampling and weight variables were stratified and analysis was conducted accounting for the complex sampling design. Analysis of covariance was used to compare the geometric mean of urine NNAL concentrations and log-transformed urine NNAL level among smoking status with weighted survey design. Post hoc paired comparisons with Bonferroni adjustment was performed according to smoking status. RESULTS: The estimated geometric mean concentrations of urine NNAL were 1.974 ± 0.091, 14.349 ± 5.218, 89.002 ± 11.444, and 117.597 ± 5.459 pg/mL in past-smoker, e-cigar only, dual-user, and cigarette only smoker groups, respectively. After fully adjusting, log-transformed urine NNAL level was significantly different among groups (P < 0.001). Compared with the past-smoker group, e-cigar only, dual-user, and cigarette only smoker groups showed significantly higher log-transformed urine NNAL concentrations in post hoc test (all P < 0.05). CONCLUSION: E-cigar only, dual-user, and cigarette only smoker groups showed significantly higher geometric mean concentrations of urine NNAL than the past-smoker group. Conventional cigarette, dual users, and e-cigar users can potentially show harmful health effects from NNAL.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Nitrosaminas , Produtos do Tabaco , Humanos , Carcinógenos/análise , Fumar , Nitrosaminas/urina , Inquéritos Nutricionais
5.
Eur Arch Otorhinolaryngol ; 280(11): 4969-4977, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37389593

RESUMO

PURPOSE: Worldwide, the incidence of chronic fungal rhinosinusitis (CFRS) has increased. Although ageing leads to weakening of the immune system, which increases susceptibility to CFRS, the CFRS characteristics in geriatric patients are unclear. Therefore, we comparatively analysed the clinical characteristics of CFRS in geriatric and non-geriatric patients. METHODS: This retrospective analysis compared the demographics, rhinologic symptoms, multiple allergen simultaneous tests, olfactory function tests, paranasal sinus computed tomography findings, and outcomes of 131 patients with CFRS who underwent functional endoscopic sinus surgery and 131 enrolled patients were divided in geriatric (> 65 years) and non-geriatric (≤ 65 years) groups. RESULTS: Among the geriatric and non-geriatric participants (n = 65, 49.6% and n = 66, 50.4%, respectively), hypertension and diabetes mellitus were more common in the geriatric group. Demographics, including symptoms, showed no significant intergroup differences. Normosmia and hyposmia were significantly less prevalent, whereas phantosmia and parosmia were more prevalent in the geriatric group than in the non-geriatric group (p = 0.03 and p = 0.01, respectively). Sphenoidal sinus involvement was significantly higher in geriatric patients than in non-geriatric patients (p = 0.02). CONCLUSION: Based on greater sphenoidal sinus involvement, a deeper anatomical area is more vulnerable to fungal infection in the geriatric group than in the non-geriatric group. Increasing clinicians' awareness of CFRS in geriatric patients with olfactory dysfunction, including phantosmia and parosmia, is important for early intervention.


Assuntos
Transtornos do Olfato , Rinite , Sinusite , Humanos , Idoso , Estudos Retrospectivos , Rinite/complicações , Rinite/epidemiologia , Rinite/microbiologia , Sinusite/diagnóstico por imagem , Sinusite/epidemiologia , Sinusite/microbiologia , Transtornos do Olfato/etiologia , Doença Crônica , República da Coreia/epidemiologia
6.
J Craniofac Surg ; 34(3): e233-e235, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36221172

RESUMO

Heterotopic ossification (HO) refers to the mature lamellar bone structure that develops locally in soft-tissue sites. Heterotopic ossification is known to occur mainly in the traumatic area or the muscle and joint capsule after surgery such as total hip arthroplasty or total knee arthroplasty. The pathophysiological cause of HO is not precisely known, but it seems to be related to some genetic predisposition. Craniomaxillofacial HO is rare and, in several reported cases, is primarily related to previous surgeries involving the masticatory muscles. The authors report on a patient who underwent endoscopic removal of a bone mass in the forehead. He completely denied any history of forehead trauma or surgery. There were no scars, trauma, or surgical marks found on the patient's forehead. Preoperative magnetic resonance imaging showed that the mass was granuloma, but histological examination after surgical removal confirmed it as HO.


Assuntos
Testa , Ossificação Heterotópica , Masculino , Humanos , Testa/cirurgia , Testa/patologia , Ossificação Heterotópica/diagnóstico por imagem , Ossificação Heterotópica/cirurgia , Ossificação Heterotópica/etiologia , Endoscopia/efeitos adversos , Imageamento por Ressonância Magnética/efeitos adversos
7.
Sensors (Basel) ; 23(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38067858

RESUMO

In the rapidly evolving urban advanced mobility (UAM) sphere, Vehicular Ad Hoc Networks (VANETs) are crucial for robust communication and operational efficiency in future urban environments. This paper quantifies VANETs to improve their reliability and availability, essential for integrating UAM into urban infrastructures. It proposes a novel Stochastic Petri Nets (SPN) method for evaluating VANET-based Vehicle Communication and Control (VCC) architectures, crucial given the dynamic demands of UAM. The SPN model, incorporating virtual machine (VM) migration and Edge Computing, addresses VANET integration challenges with Edge Computing. It uses stochastic elements to mirror VANET scenarios, enhancing network robustness and dependability, vital for the operational integrity of UAM. Case studies using this model offer insights into system availability and reliability, guiding VANET optimizations for UAM. The paper also applies a Design of Experiments (DoE) approach for a sensitivity analysis of SPN components, identifying key parameters affecting system availability. This is critical for refining the model for UAM efficiency. This research is significant for monitoring UAM systems in future cities, presenting a cost-effective framework over traditional methods and advancing VANET reliability and availability in urban mobility contexts.

8.
Entropy (Basel) ; 25(8)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37628159

RESUMO

Increasing wealth inequality is a significant global issue that demands attention. While the distribution of wealth varies across countries based on their economic stages, there is a universal trend observed in the distribution function. Typically, regions with lower wealth values exhibit an exponential distribution, while regions with higher wealth values demonstrate a power-law distribution. In this review, we introduce measures that effectively capture wealth inequality and examine wealth distribution functions within the wealth exchange model. Drawing inspiration from the field of econophysics, wealth exchange resulting from economic activities is likened to a kinetic model, where molecules collide and exchange energy. Within this framework, two agents exchange a specific amount of wealth. As we delve into the analysis, we investigate the impact of various factors such as tax collection, debt allowance, and savings on the wealth distribution function when wealth is exchanged. These factors play a crucial role in shaping the dynamics of wealth distribution.

9.
Am J Respir Cell Mol Biol ; 66(4): 415-427, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35073245

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease characterized by fibroproliferative matrix molecule accumulation, collagen deposition, and apoptosis. Activated leukocyte cell-adhesion molecule (ALCAM; CD166) is a cell-adhesion molecule that has been implicated in adhesive and migratory attribution, including leukocyte homing and trafficking and cancer metastasis. We investigated the role of ALCAM on pulmonary fibrosis development in murine models. Thus, a bleomycin-induced pulmonary fibrosis model was established with wild-type and ALCAM-/- mice. Pulmonary fibrosis was also induced in transforming growth factor-ß1 (TGF-ß1)-transgenic mice that conditionally overexpress TGF-ß1 upon doxycycline administration. In both models, observed reduced ALCAM levels in lung tissue and BAL fluid in pulmonary fibrosis-induced wild-type mice compared with control mice. We also observed reduced ALCAM expression in the lung tissue of patients with pulmonary fibrosis compared with normal lung tissue. ALCAM-/- mice showed an exacerbated lung fibrosis response compared with wild-type mice, and this was accompanied by increased cell death. Further investigation for identification of the signaling pathway revealed that PI3K and ERK signaling pathways are involved in bleomycin-induced fibrosis. Collectively, these results highlight that ALCAM plays a protective role in the pathogenesis of pulmonary fibrosis that inhibits epithelial cell apoptosis through the PI3K-Akt signaling pathway. Our findings demonstrate the potential of ALCAM as a therapeutic target for IPF and may aid the development of new strategies for the management and treatment of patients with IPF.


Assuntos
Molécula de Adesão de Leucócito Ativado , Antígenos CD/metabolismo , Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas Fetais/metabolismo , Fibrose Pulmonar Idiopática , Molécula de Adesão de Leucócito Ativado/metabolismo , Animais , Bleomicina , Humanos , Fibrose Pulmonar Idiopática/metabolismo , Leucócitos/patologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
10.
Biochem Biophys Res Commun ; 592: 106-112, 2022 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-35033868

RESUMO

Viral respiratory infection causes inflammatory lung disease. Chitinase 3-like 1 (CHI3L1) contributes to airway inflammation, but its role in human airway epithelial cells following viral infection is unclear. Thus, we investigated whether CHI3L1 regulates inflammatory responses caused by viral infections in airway epithelial cells. Human bronchial epithelial cells, BEAS-2B, were stimulated with a synthetic analog of viral double-stranded RNA, polyinosinic:polycytidylic acid (poly(I:C)). To confirm the specific role of CHI3L1, CHI3L1 was knocked down in BEAS-2B cells using shRNA lentivirus. The expression of CHI3L1 and proinflammatory cytokines such as IL-8 and phosphorylation of mitogen-activated protein kinase (MAPK) pathways were analyzed. In addition to poly(I:C), BEAS-2B cells were infected with the human respiratory syncytial virus (RSV) A2 strain, and CHI3L1 and IL-8 expression was analyzed. Stimulating the cells with poly(I:C) increased CHI3L1 and IL-8 expression, whereas IL-8 expression was abrogated in CHI3L1 knockdown BEAS-2B cells. Poly(I:C) stimulation of BEAS-2B cells resulted in phosphorylation of MAPK pathways, and inhibition of MAPK pathways significantly abolished IL-8 secretion. Phosphorylation of MAPK pathways was diminished in CHI3L1 knockdown BEAS-2B cells. Infection with RSV increased CHI3L1 and IL-8 expression. IL-8 expression induced by RSV infection was abrogated in CHI3L1 knockdown cells. In conclusion, CHI3L1 may be involved in IL-8 secretion by regulating MAPK pathways during respiratory viral infections in airway epithelial cells.


Assuntos
Proteína 1 Semelhante à Quitinase-3/metabolismo , Células Epiteliais/metabolismo , Interleucina-8/metabolismo , Pulmão/citologia , RNA de Cadeia Dupla/metabolismo , Linhagem Celular , Citocinas/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/virologia , Humanos , Mediadores da Inflamação/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Poli I-C/farmacologia , Infecções por Vírus Respiratório Sincicial/patologia , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/efeitos dos fármacos , Vírus Sincicial Respiratório Humano/fisiologia
11.
Anesthesiology ; 136(1): 181-205, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34499087

RESUMO

Pulmonary atelectasis is common in the perioperative period. Physiologically, it is produced when collapsing forces derived from positive pleural pressure and surface tension overcome expanding forces from alveolar pressure and parenchymal tethering. Atelectasis impairs blood oxygenation and reduces lung compliance. It is increasingly recognized that it can also induce local tissue biologic responses, such as inflammation, local immune dysfunction, and damage of the alveolar-capillary barrier, with potential loss of lung fluid clearance, increased lung protein permeability, and susceptibility to infection, factors that can initiate or exaggerate lung injury. Mechanical ventilation of a heterogeneously aerated lung (e.g., in the presence of atelectatic lung tissue) involves biomechanical processes that may precipitate further lung damage: concentration of mechanical forces, propagation of gas-liquid interfaces, and remote overdistension. Knowledge of such pathophysiologic mechanisms of atelectasis and their consequences in the healthy and diseased lung should guide optimal clinical management.


Assuntos
Complicações Intraoperatórias/fisiopatologia , Pulmão/fisiopatologia , Assistência Perioperatória/métodos , Atelectasia Pulmonar/fisiopatologia , Atelectasia Pulmonar/terapia , Animais , Diafragma/diagnóstico por imagem , Diafragma/fisiopatologia , Humanos , Complicações Intraoperatórias/diagnóstico por imagem , Complicações Intraoperatórias/terapia , Pulmão/diagnóstico por imagem , Assistência Perioperatória/tendências , Atelectasia Pulmonar/diagnóstico por imagem , Respiração Artificial/efeitos adversos , Respiração Artificial/tendências
12.
Nanotechnology ; 34(2)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36198255

RESUMO

This study investigates the effects of hydrogen post-treatment on 3D NAND flash memory. Hydrogen post-treatment annealing (PTA) is suggested to passivate the defects in the tunneling oxide/poly-Si interface and inside the poly-Si channel. However, excess hydrogen PTA can release hydrogen atoms from the passivated defects, which may degrade device performance. Therefore, it is important to determine the appropriate PTA condition for optimization of the device performance. Three different conditions for hydrogen PTA, namely Reference, H, and H++, are applied to observe the effects on device performance. The activation energy (Ea) of the device parameters was extracted according to the hydrogen PTA condition to analyze the effects. The extractedEais about 74 meV for Reference, 53 meV for H, and 58 meV for H++conditions, with the best performance observed at the H condition. Optimal hydrogen PTA shows the best on-current (51% higher than Reference) and stable short-term retention (66% suppressedΔVTthan Reference) in 9X stacked 3D NAND flash memory.

13.
BMC Anesthesiol ; 22(1): 136, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35501692

RESUMO

BACKGROUND: Adjuvant regional anesthesia is often selected for patients or procedures with high risk of pulmonary complications after general anesthesia. The benefit of adjuvant regional anesthesia to reduce postoperative pulmonary complications remains uncertain. In a prospective observational multicenter study, patients scheduled for non-cardiothoracic surgery with at least one postoperative pulmonary complication surprisingly received adjuvant regional anesthesia more frequently than those with no complications. We hypothesized that, after adjusting for surgical and patient complexity variables, the incidence of postoperative pulmonary complications would not be associated with adjuvant regional anesthesia. METHODS: We performed a secondary analysis of a prospective observational multicenter study including 1202 American Society of Anesthesiologists physical status 3 patients undergoing non-cardiothoracic surgery. Patients were classified as receiving either adjuvant regional anesthesia or general anesthesia alone. Predefined pulmonary complications within the first seven postoperative days were prospectively identified. Groups were compared using bivariable and multivariable hierarchical logistic regression analyses for the outcome of at least one postoperative pulmonary complication. RESULTS: Adjuvant regional anesthesia was performed in 266 (22.1%) patients and not performed in 936 (77.9%). The incidence of postoperative pulmonary complications was greater in patients receiving adjuvant regional anesthesia (42.1%) than in patients without it (30.9%) (site adjusted p = 0.007), but this association was not confirmed after adjusting for covariates (adjusted OR 1.37; 95% CI, 0.83-2.25; p = 0.165). CONCLUSION: After adjusting for surgical and patient complexity, adjuvant regional anesthesia versus general anesthesia alone was not associated with a greater incidence of postoperative pulmonary complications in this multicenter cohort of non-cardiothoracic surgery patients.


Assuntos
Anestesia por Condução , Anestesia por Condução/efeitos adversos , Anestesia Geral/efeitos adversos , Anestesia Geral/métodos , Humanos , Incidência , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Período Pós-Operatório
14.
J Craniofac Surg ; 33(6): 1674-1678, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34879016

RESUMO

BACKGROUND: Revisional malarplasty is the most frequently performed and difficult to perform revision surgery among facial contouring surgeries. The incidence of postoperative complications and need for revision surgery is increasing because of indiscriminate malar reduction through a narrow surgical space. The authors analyzed cases of revisional malarplasty secondary to complications. METHODS: The authors analyzed the time required and technique used in 172 patients who underwent revisional malarplasty in the past 3 years. The incision made for the approach and the graft material used for reconstruction were also investigated. RESULTS: Of 172 patients, 35 (20.3%) underwent emergency revision. Furthermore, 71 (41.2%) required an intraoral incision, and 101 (58.8%) required a coronal incision. A total of 81(47.1%) patients required artificial or autogenous bone grafts. CONCLUSIONS: Patients with failed malarplasty should receive immediate intervention to prevent functional and cosmetic problems. When bone resorption occurs due to unfavorable union or nonunion, reconstruction using appropriate autologous tissue can prevent functional impairment and long-term cosmetic problems.


Assuntos
Procedimentos de Cirurgia Plástica , Zigoma , Transplante Ósseo , Face/cirurgia , Humanos , Procedimentos de Cirurgia Plástica/métodos , Reoperação , Estudos Retrospectivos , Zigoma/cirurgia
15.
Sensors (Basel) ; 22(4)2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35214499

RESUMO

The spread of the Coronavirus (COVID-19) pandemic across countries all over the world urges governments to revolutionize the traditional medical hospitals/centers to provide sustainable and trustworthy medical services to patients under the pressure of the huge overload on the computing systems of wireless sensor networks (WSNs) for medical monitoring as well as treatment services of medical professionals. Uncertain malfunctions in any part of the medical computing infrastructure, from its power system in a remote area to the local computing systems at a smart hospital, can cause critical failures in medical monitoring services, which could lead to a fatal loss of human life in the worst case. Therefore, early design in the medical computing infrastructure's power and computing systems needs to carefully consider the dependability characteristics, including the reliability and availability of the WSNs in smart hospitals under an uncertain outage of any part of the energy resources or failures of computing servers, especially due to software aging. In that regard, we propose reliability and availability models adopting stochastic Petri net (SPN) to quantify the impact of energy resources and server rejuvenation on the dependability of medical sensor networks. Three different availability models (A, B, and C) are developed in accordance with various operational configurations of a smart hospital's computing infrastructure to assimilate the impact of energy resource redundancy and server rejuvenation techniques for high availability. Moreover, a comprehensive sensitivity analysis is performed to investigate the components that impose the greatest impact on the system availability. The analysis results indicate different impacts of the considered configurations on the WSN's operational availability in smart hospitals, particularly 99.40%, 99.53%, and 99.64% for the configurations A, B, and C, respectively. This result highlights the difference of 21 h of downtime per year when comparing the worst with the best case. This study can help leverage the early design of smart hospitals considering its wireless medical sensor networks' dependability in quality of service to cope with overloading medical services in world-wide virus pandemics.


Assuntos
COVID-19 , Rejuvenescimento , Hospitais , Humanos , Reprodutibilidade dos Testes , SARS-CoV-2
16.
Sensors (Basel) ; 22(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36015797

RESUMO

In urban mobility, Vehicular Ad Hoc Networks (VANETs) provide a variety of intelligent applications. By enhancing automobile traffic management, these technologies enable advancements in safety and help decrease the frequency of accidents. The transportation system can now follow the development and growth of cities without sacrificing the quality and organisation of its services thanks to safety apps that include collision alerts, real-time traffic information, and safe driving applications, among others. Applications can occasionally demand a lot of computing power, making their processing impractical for cars with limited onboard processing capacity. Offloading of computation is encouraged by such a restriction. However, because vehicle mobility operations are dynamic, communication times (also known as link lifetimes) between nodes are frequently short. VANET applications and processes are impacted by such communication delays (e.g., the offloading decision when using the Computational Offloading technique). Making an accurate prediction of the link lifespan between vehicles is therefore challenging. The effectiveness of the communication time estimation is currently constrained by the link lifespan prediction methods used in the computational offloading process. This work investigates five machine learning (ML) algorithms to predict the link lifetime between nodes in VANETs in different scenarios. We propose the procedures required to carry out the link lifetime prediction method using existing ML techniques. The tactic creates datasets with the features the models need to learn and be trained. The SVR and XGBoost algorithms that were selected as part of the assessment process were trained. To make the prediction using the trained models, we modified the lifespan prediction function from an offloading approach. To determine the viability of applying link lifespan predictions from the models trained in the road and urban scenarios, we conducted a performance study. The findings indicate that compared to the conventional prediction strategy described in the literature, the suggested link lifetime prediction via regression approaches decreases prediction error rates. An offloading method from the literature is extended by the selected SVR. The task loss and recovery rates might be significantly reduced using the SVR. XGBoost outperformed its ML competitors in task recovery or drop rate by 70% to 80% in an assessed hypothesis compared to an offloading choice technique in the literature. With greater offloading rates from an application on the VANET, this effort is intended to give better efficiency in estimating this data using machine learning in various vehicular settings.


Assuntos
Condução de Veículo , Redes de Comunicação de Computadores , Algoritmos , Aprendizado de Máquina , Meios de Transporte
17.
J Environ Manage ; 305: 114412, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34991028

RESUMO

From 2022, industrial wastewater discharge regulations in South Korea will replace chemical oxygen demand (CODMn) with total organic carbon (TOC). A shift from CODMn to TOC is a pioneering change in protecting water bodies from organic contaminants. However, several industries are struggling to meet these TOC requirements even though their effluents met the CODMn limits. Effluent CODMn/TOC ratios (1.28 ± 0.64) found in our study were lower than the CODMn/TOC coefficients (1.33-1.80) suggested by the Ministry of Environment in South Korea. Aliphatic and particulate organic matter contents in effluents likely influenced the CODMn/TOC ratio. Regardless of the industrial category, dissolved organic carbon often consists of low molecular weight neutrals, hydrophobic organic carbon, and protein-like substances in raw and treated industrial wastewaters. The present study also revealed that TOC and CODMn represented different organic matter fractions in the paper mill and oil refinery wastewater, whereas the industrial park wastewater showed similar dissolved organic matter characteristics. Specifically, CODMn was effective in the determination of humic content in paper mill wastewater but was underestimated in oil refinery wastewater. Additionally, only paper mill effluents exceeded the TOC requirements (4 of 6 samples) and required an additional post-treatment process owing to higher organic loads.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Análise da Demanda Biológica de Oxigênio , Carbono , Matéria Orgânica Dissolvida , Resíduos Industriais , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análise
18.
Entropy (Basel) ; 24(2)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35205440

RESUMO

We studied the prisoner's dilemma game as applied to signed networks. In signed networks, there are two types of links: positive and negative. To establish a payoff matrix between players connected with a negative link, we multiplied the payoff matrix between players connected with a positive link by -1. To investigate the effect of negative links on cooperating behavior, we performed simulations for different negative link densities. When the negative link density is low, the density of the cooperator becomes zero because there is an increasing temptation payoff, b. Here, parameter b is the payoff received by the defector from playing the game with a cooperator. Conversely, when the negative link density is high, the cooperator density becomes almost 1 as b increases. This is because players with a negative link will suffer more payoff damage if they do not cooperate with each other. The negative link forces players to cooperate, so cooperating behavior is enhanced.

19.
Am J Physiol Lung Cell Mol Physiol ; 321(5): L827-L836, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34524905

RESUMO

We previously reported that extracellular vesicles (EVs) released during Escherichia coli (E. coli) bacterial pneumonia were inflammatory, and administration of high molecular weight hyaluronic acid (HMW HA) suppressed several indices of acute lung injury (ALI) from E. coli pneumonia by binding to these inflammatory EVs. The current study was undertaken to study the therapeutic effects of HMW HA in ex vivo perfused human lungs injured with Pseudomonas aeruginosa (PA)103 bacterial pneumonia. For lungs with baseline alveolar fluid clearance (AFC) <10%/h, HMW HA 1 or 2 mg was injected intravenously after 1 h (n = 4-9), and EVs released during PA pneumonia were collected from the perfusate over 6 h. For lungs with baseline AFC > 10%/h, HMW HA 2 mg was injected intravenously after 1 h (n = 6). In vitro experiments were conducted to evaluate the effects of HA on inflammation and bacterial phagocytosis. For lungs with AFC < 10%/h, administration of HMW HA intravenously significantly restored AFC and numerically decreased protein permeability and alveolar inflammation from PA103 pneumonia but had no effect on bacterial counts at 6 h. However, HMW HA improved bacterial phagocytosis by human monocytes and neutrophils and suppressed the inflammatory properties of EVs released during pneumonia on monocytes. For lungs with AFC > 10%/h, administration of HMW HA intravenously improved AFC from PA103 pneumonia but had no significant effects on protein permeability, inflammation, or bacterial counts. In the presence of impaired alveolar epithelial transport capacity, administration of HMW HA improved the resolution of pulmonary edema from Pseudomonas PA103 bacterial pneumonia.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Ácido Hialurônico/farmacologia , Pneumonia Bacteriana/tratamento farmacológico , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Edema Pulmonar/tratamento farmacológico , Lesão Pulmonar Aguda/microbiologia , Lesão Pulmonar Aguda/patologia , Adulto , Vesículas Extracelulares/patologia , Feminino , Humanos , Pulmão/efeitos dos fármacos , Pulmão/microbiologia , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Neutrófilos/imunologia , Técnicas de Cultura de Órgãos , Fagocitose/efeitos dos fármacos , Pneumonia Bacteriana/microbiologia , Pneumonia Bacteriana/patologia , Edema Pulmonar/microbiologia , Edema Pulmonar/patologia , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/microbiologia , Síndrome do Desconforto Respiratório/patologia
20.
Nanotechnology ; 32(16): 165202, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33302263

RESUMO

Through time-dependent defect spectroscopy and low-frequency noise measurements, we investigate and characterize the differences of carrier trapping processes occurred by different interfaces (top/sidewall) of the gate-all-around silicon nanosheet field-effect transistor (GAA SiNS FET). In a GAA SiNS FET fabricated by the top-down process, the traps at the sidewall interface significantly affect the device performance as the width decreases. Compare to expectations, as the width of the device decreases, the subthreshold swing (SS) increases from 120 to 230 mV/dec, resulting in less gate controllability. In narrow-width devices, the effect of traps located at the sidewall interface is significantly dominant, and the 1/f 2 noise, also known as generation-recombination (G-R) noise, is clearly appeared with an increased time constant (τ i ). In addition, the probability density distributions for the normalized current fluctuations (ΔI D) show only one Gaussian in wide-width devices, whereas they are separated into four Gaussians with increased in narrow-width devices. Therefore, fitting is performed through the carrier number fluctuation-correlated with mobility fluctuations model that separately considered the effects of sidewall. In narrow-width GAA SiNS FETs, consequently, the extracted interface trap densities (N T ) distribution becomes more dominant, and the scattering parameter ([Formula: see text]) distribution increases by more than double.

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