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1.
Anesth Analg ; 138(5): 1031-1042, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38335150

RESUMO

BACKGROUND: Postoperative delirium (POD) is a common form of postoperative brain dysfunction, especially in the elderly. However, its risk factors remain largely to be determined. This study aimed to investigate whether (1) preoperative diabetes is associated with POD after elective orthopedic surgery and (2) intraoperative frontal alpha power is a mediator of the association between preoperative diabetes and POD. METHODS: This was a prospective matched cohort study of patients aged 60 years or more, with a preoperative diabetes who underwent elective orthopedic surgery. Nondiabetic patients were matched 1:1 to diabetic patients in terms of age, sex, and type of surgery. Primary outcome was occurrence of POD, assessed using the 3-minute Diagnostic Confusion Assessment Method (3D-CAM) once daily from 6 pm to 8 pm during the postoperative days 1-7 or until discharge. Secondary outcome was the severity of POD which was assessed for all participants using the short form of the CAM-Severity. Frontal electroencephalogram (EEG) was recorded starting before induction of anesthesia and lasting until discharge from the operating room. Intraoperative alpha power was calculated using multitaper spectral analyses. Mediation analysis was used to estimate the proportion of the association between preoperative diabetes and POD that could be explained by intraoperative alpha power. RESULTS: A total of 138 pairs of eligible patients successfully matched 1:1. After enrollment, 6 patients in the diabetes group and 4 patients in the nondiabetes group were excluded due to unavailability of raw EEG data. The final analysis included 132 participants with preoperative diabetes and 134 participants without preoperative diabetes, with a median age of 68 years and 72.6% of patients were female. The incidence of POD was 16.7% (22/132) in patients with preoperative diabetes vs 6.0% (8/134) in patients without preoperative diabetes. Preoperative diabetes was associated with increased odds of POD after adjustment of age, sex, body mass index, education level, hypertension, arrhythmia, coronary heart disease, and history of stroke (odds ratio, 3.2; 95% confidence interval [CI], 1.4-8.0; P = .009). The intraoperative alpha power accounted for an estimated 20% (95% CI, 2.6-60%; P = .021) of the association between diabetes and POD. CONCLUSIONS: This study suggests that preoperative diabetes is associated with an increased risk of POD in older patients undergoing major orthopedic surgery, and that low intraoperative alpha power partially mediates such association.


Assuntos
Delírio , Diabetes Mellitus , Delírio do Despertar , Procedimentos Ortopédicos , Idoso , Humanos , Feminino , Masculino , Delírio do Despertar/diagnóstico , Delírio do Despertar/epidemiologia , Delírio do Despertar/etiologia , Estudos de Coortes , Estudos Prospectivos , Delírio/diagnóstico , Delírio/etiologia , Delírio/epidemiologia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Procedimentos Ortopédicos/efeitos adversos , Diabetes Mellitus/diagnóstico , Fatores de Risco
2.
Sensors (Basel) ; 22(11)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35684661

RESUMO

The uniaxial piezoelectric sensor was developed to overcome the problem of reflecting the output charge of the piezoelectric element as a combination of vectors in the three stress directions. The work performance of the uniaxial piezoelectric sensor under varying load patterns and load rates was investigated. The sensor was embedded in concrete to monitor stress, and its elastic modulus was used as the intermediate bridge to establish the correlation between the embedded sensor and the external sensor. Furthermore, a correction factor for the charge transformation strain was suggested to overcome the mismatching of the sensor's medium and the concrete. Considering related circumstances, a new stress monitoring method based on a uniaxial piezoelectric sensor was proposed, which can achieve stress whole-process monitoring in concrete and confining stress monitoring in the reinforced concrete column. The results reveal that through the proposed method, the output charge curve of the sensor has a substantial overlap with the stress waveform and high fitting linearity. The work performance of the sensor was stable, and its sensitivity was not affected by loading rate and load pattern. The sensor was embedded in concrete and can coordinate with the concrete deformation. The correction factor of strain obtained by the sensor embedded in concrete was 1.07. The relationship between the charge produced by the embedded sensor and its external calibration sensitivity may be used to implement the whole process of stress monitoring in concrete.

3.
Sensors (Basel) ; 19(8)2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-31003404

RESUMO

It is difficult to detect and evaluate the structural damage in a shield tunnel during operation because many traditional techniques based on the observation of vibrations are limited in daily monitoring in tunnels. Thus, the curvature radius of a static longitudinal settlement curve is used to identify the residual health and safety of an in-service shield tunnel. However, there are still two problems. The curvature radius is suitable for a qualitative judgment rather than a quantitative evaluation for longitudinal damage detection. Moreover, the curvature radius, which is calculated from the measured settlements of three neighboring points, gives an average damage degree in a wide scope only and is difficult to use to identify the damage's precise location. By means of the analysis of three kinds of longitudinal failure modes in a shield tunnel, this paper proposes: (1) a damage detection method based on the monitored increment of the neutral axis depth; and (2) an index to evaluate longitudinal damage. The index is composed of the residual ratios of the equivalent flexural stiffness (HFM1) and the equivalent shear stiffness (HFM3). The neutral axis position and the proposed damage index can be determined using long-gauge Fiber Bragg Grating sensors. Results from numerical simulations show that the deviation between the HFM1 and the true value residual ratio of the equivalent flexural stiffness is no more than 1.7%. The HFM3 is equal to its true value in the entire damage process. A loading experiment for a scaled-down model of a shield tunnel using long-gauge Fiber Bragg Grating sensors indicated that the errors in the HFM1 were no more than 5.0% in the case of early damage development (HFM1 ≥ 0.5). The maximum error did not exceed 9.0% even under severe damage conditions in the model. Meanwhile, the HFM3 also coincided with its true value in the entire testing process.

4.
Sensors (Basel) ; 18(12)2018 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-30477164

RESUMO

Prestress loss evaluation in prestressed strands is essential for prestressed structures. However, the sensors installed outside the duct can only measure the total prestress loss. The sensors attached on strands inside the duct also have several problems, such as inadequate durability in an aggressive environment and vulnerability to damage during tensioning. This paper proposes a new installation method for long-gauge fiber Bragg grating (LFBG) sensors to prevent accidental damage. Then the itemized prestress losses were determined in each stage of the pre-tensioning and post-tensioning according to the LFBG measurements. We verified the applicability of the LFBG sensors for prestress monitoring and the accuracy of the proposed prestress loss calculation method during pre-tensioning and post-tensioning. In the pre-tensioning case, the calculated prestress losses had less deviation from the true losses than those obtained from foil-strain gauges, and the durability of the LFBG sensors was better than foil-strain gauges, whereas in post-tensioning case, the calculated prestress losses were close to those derived from theoretical predictions. Finally, we monitored prestress variation in the strand for 90 days. The itemized prestress losses at each stages of post-tensioning were obtained by the proposed calculation method to show the prospect of the LFBG sensors in practical evaluation.

5.
Sensors (Basel) ; 17(4)2017 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-28350324

RESUMO

This study aimed to investigate the inter-limb coordination pattern and the stability, intensity, and complexity of the trunk and limbs motions in human crawling under different speeds. Thirty healthy human adults finished hands-knees crawling trials on a treadmill at six different speeds (from 1 km/h to 2.5 km/h). A home-made multi-channel acquisition system consisting of five 3-axis accelerometers (ACC) and four force sensors was used for the data collection. Ipsilateral phase lag was used to represent inter-limb coordination pattern during crawling and power, harmonic ratio, and sample entropy of acceleration signals were adopted to depict the motion intensity, stability, and complexity of trunk and limbs respectively. Our results revealed some relationships between inter-limb coordination patterns and the stability and complexity of trunk movement. Trot-like crawling pattern was found to be the most stable and regular one at low speed in the view of trunk movement, and no-limb-pairing pattern showed the lowest stability and the greatest complexity at high speed. These relationships could be used to explain why subjects tended to avoid no-limb-pairing pattern when speed was over 2 km/h no matter which coordination type they used at low speeds. This also provided the evidence that the central nervous system (CNS) chose a stable inter-limb coordination pattern to keep the body safe and avoid tumbling. Although considerable progress has been made in the study of four-limb locomotion, much less is known about the reasons for the variety of inter-limb coordination. The research results of the exploration on the inter-limb coordination pattern choice during crawling from the standpoint of the motion stability, intensity, and complexity of trunk and limbs sheds light on the underlying motor control strategy of the human CNS and has important significance in the fields of clinical diagnosis, rehabilitation engineering, and kinematics research.


Assuntos
Movimento (Física) , Adulto , Fenômenos Biomecânicos , Mãos , Humanos , Locomoção , Tronco
6.
PLoS One ; 18(2): e0281643, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36827393

RESUMO

The coupling coordination mechanism between economic resilience and high-quality economic development is clarified not only to improve the capacity of economies to withstand external shocks but also to boost the level of sustainable economic development. However, economic resilience and economic quality research are still in their infancy. This study constructs an economic resilience indicator system based on the data of 28 prefecture-level cities in the urban agglomeration in the middle reaches of the Yangtze River (UAMRYR) from 2010-2019. The entropy approach was then coupled with the coupling coordination model to determine the level of coupling coordination between the two. Finally, the geographical detector was employed to reveal the coupling coordination process and driving elements. This study demonstrates that: (1) The economic resilience and high-quality economic development of the UAMRYR are on the rise; (2) The coupling coordination degree between economic resilience and high-quality economic development is improving, with the average value increasing from 0.33 in 2010 to 0.46 in 2019, exhibiting a Core-Periphery spatial distribution pattern with Wuhan, Changsha, and Nanchang as the core; (3) The economic resilience resistance subsystem plays a substantial role in the driving influence of the coupling coordination degree, where the total retail sales of consumer goods indicator have an explanatory power of 0.8 or higher for coupled coordination. Innovation and inclusiveness thoroughly drive the coupling coordination degree among the five subsystems of high-quality economic development, where the q-value of the number of urban basic endowment insurance participants index is at least 0.9. Additionally, the interplay of the components demonstrates a complementary enhancement impact and a two-factor enhancement effect; (4) Economic resilience and high-quality economic development are complementary and provide a powerful incentive for the sustainable development of urban economic systems to achieve higher quality, more efficient, more egalitarian, and more sustainable economic development. Overall, this study improves the analysis of mechanism between economic resilience and high-quality economic development, and it provides more targeted guidance for economic development in the UARMRYR.


Assuntos
Desenvolvimento Econômico , Urbanização , Humanos , Rios , Cidades , Desenvolvimento Sustentável , China
7.
Sci Total Environ ; 867: 161587, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36638988

RESUMO

Soil microbial carbon use efficiency (CUE) is a vital physiological parameter in assessing carbon turnover. Yet, how the microbial assemblies with distinct trophic strategies regulate the soil microbial CUE remains elusive. Based on the oligotrophic-copiotrophic framework, we explored the role of microbial taxa with different trophic strategies in mediating microbial CUE (determined by a 13C-labeled approach) along the vegetation primary succession in Hailuogou glacier retreat area of the southeastern Tibetan Plateau. Results showed that soil microbial CUE ranged from 0.54 to 0.72 (averaging 0.62 ± 0.01 across all samples) and increased staggeringly along the vegetation succession. Microbial assemblies with distinct trophic strategies were crucial regulators of soil microbial CUE. Specifically, microbial CUE increased with microbial oligotroph: copiotroph ratios, oligotroph-dominated stage had a higher microbial CUE than copiotroph-dominated ones. The prevalence of oligotrophic members would be the underlying microbial mechanism for the high microbial CUE. Given that oligotrophs predominate in more recalcitrant carbon soils and their higher microbial CUE, we speculate that oligotrophs are likely to potentially enhance carbon sequestration in soils. In addition, the responses of the microbial CUE to fungal oligotroph: copiotroph ratios were higher than bacterial ones. Fungal taxa may play a dominant role in shaping microbial CUE relative to bacterial members. Overall, our results constructed close associations between microbial trophic strategies and CUE and provide direct evidence regarding how microbial trophic strategies regulate microbial CUE. This study is a significant step forward for elucidating the physiological mechanisms regulating microbial CUE and has significant implications for understanding microbial-mediated carbon cycling processes.


Assuntos
Camada de Gelo , Solo , Tibet , Camada de Gelo/microbiologia , Carbono , Microbiologia do Solo , Bactérias
8.
Mater Horiz ; 10(12): 5898-5906, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37870084

RESUMO

Taking the advantages of hierarchical nitrogen-doped carbon nanocages (hNCNCs) with nanocavities for encapsulation and multiscale micro-meso-macropores/high conductivity for mass/electron synergistic transportation, a conversion-type CuO anode material is confined inside hNCNCs for potassium storage. The so-obtained yolk-shelled CuO@hNCNC hybrids have tunable CuO contents in the range of 11.7-63.7 wt%. The unique architecture leads to the loss-free pulverization of the active components during charge/discharge, which increases the surface-controlled charge storage, shortens the K+ solid diffusion lengths with an enlarged K+ diffusion coefficient, and meanwhile enhances the rate capability and durability. Consequently, the optimized CuO@hNCNC delivers a high specific capacity of 498 mA h g-1 at 0.1 A g-1 and 194 mA h g-1 at 10.0 A g-1 based on the total mass of CuO@hNCNC, and a long-term stability. The capacity based on the CuO active component reaches a record-high 522 mA h g-1 at 1.0 A g-1 after 2000 cycles, which is ca. 2.5 times the state-of-the-art value in the literature. The evolution of the cycling performance with CuO loading is well understood based on the loss-free pulverization. This study demonstrates a new strategy to turn the generally harmful pulverization of active components into a beneficial factor for K+ storage, which paves the way for exploring high-performance anodes for rechargeable batteries.

9.
Neuropsychiatr Dis Treat ; 19: 1195-1206, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37220563

RESUMO

Purpose: The study aims to clarify the negative psychological state and resilience impairments of schizophrenia (SCZ) with metabolic syndrome (MetS) while evaluating their potential as risk factors. Patients and Methods: We recruited 143 individuals and divided them into three groups. Participants were evaluated using the Positive and Negative Syndrome Scale (PANSS), Hamilton Depression Rating Scale (HAMD)-24, Hamilton Anxiety Rating Scale (HAMA)-14, Automatic Thoughts Questionnaire (ATQ), Stigma of Mental Illness scale and Connor-Davidson Resilience Scale (CD-RISC). Serum biochemical parameters were measured by automatic biochemistry analyzer. Results: The score of ATQ was highest in the MetS group (F = 14.5, p < 0.001), and the total score of CD-RISC, subscale tenacity score and subscale strength score of CD-RISC were lowest in the MetS group (F = 8.54, p < 0.001; F = 5.79, p = 0.004; F = 10.9, p < 0.001). A stepwise regression analysis demonstrated that a negative correlation was observed among the ATQ with employment status, high-density lipoprotein (HDL-C), and CD-RISC (ß=-0.190, t=-2.297, p = 0.023; ß=-0.278, t=-3.437, p = 0.001; ß=-0.238, t=-2.904, p = 0.004). A positive correlation was observed among the ATQ with waist, TG, WBC, and stigma (ß=0.271, t = 3.340, p = 0.001; ß=0.283, t = 3.509, p = 0.001; ß=0.231, t = 2.815, p = 0.006; ß=0.251, t=-2.504, p = 0.014). The area under the receiver-operating characteristic curve analysis showed that among all independent predictors of ATQ, the TG, waist, HDL-C, CD-RISC, and stigma presented excellent specificity at 0.918, 0.852, 0.759, 0.633, and 0.605, respectively. Conclusion: Results suggested that the non-MetS and MetS groups had grievous sense of stigma, particularly, high degree of ATQ and resilience impairment was shown by the MetS group. The TG, waist, HDL-C of metabolic parameters, CD-RISC, and stigma presented excellent specificity to predict ATQ, and the waist showed excellent specificity to predict low resilience level.

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