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1.
Environ Res ; 243: 117853, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38070856

RESUMO

Biochar-based organic fertilizer is a new type of ecological fertilizer formulated with organic fertilizers using biochar as the primary conditioning agent, which has received wide attention and application in recent years. This study conducted a comprehensive bibliometric analysis of the main hot spots and research trends in the field of biochar-based organic fertilizer research by collecting indicators (publication year, number, prominent authors, and research institutions) in the Web of Science database. The results showed that the research in biochar-based organic fertilizer has been in a rapid development stage since 2015, with exponential growth in publications number; the main institution with the highest publications number was Northwest Agriculture & Forestry University; the researchers with the highest number of publications was Mukesh Kumar Awasthi; the most publications country is China by Dec 30, 2022. The hot spots of biochar-based organic fertilizer research have been nitrogen utilization, greenhouse gas emission, composting product quality and soil fertility. Biochar reduces ammonia volatilization and greenhouse gas emissions from compost mainly through adsorption. The results showed that adding 10% biochar was an effective measure to achieve co-emission reduction of ammonia and greenhouse gases in composting process. In addition, biochar modification or combination with other additives should be the focus of future research to mitigate ammonia and greenhouse gas emissions from composting processes.


Assuntos
Carvão Vegetal , Compostagem , Gases de Efeito Estufa , Humanos , Gases de Efeito Estufa/análise , Amônia , Fertilizantes/análise , Volatilização , Nitrogênio/análise , Solo , Agricultura , Óxido Nitroso
2.
Heart Lung Circ ; 33(4): 486-492, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38423849

RESUMO

AIM: Angiotensin receptor blockers (ARBs) have been shown to inhibit restenosis in vitro and in vivo, but the evidence found in humans is inconsistent. This study aimed to evaluate the effectiveness of ARBs in preventing in-stent restenosis after percutaneous coronary intervention (PCI). METHOD: Databases including the Cochrane Library, MEDLINE, Web of Science, EMBASE, and CNKI were searched to collect randomised controlled trials on ARBs inhibiting restenosis that were published before October 2022. A total of 1,056 patients enrolled in eight trials were included in the study. RESULTS: The ARBs group showed lower target lesion revascularisation than the control group (RR 0.54; 95% CI 0.34-0.86; p=0.01), but the restenosis incidence between these two groups was not statistically significant (RR 0.85; 95% CI 0.65-1.11; p>0.05). CONCLUSION: This study found that ARBs might have a potential effect on reducing target lesion revascularisation after PCI in coronary heart disease patients but has no impact on angiographic restenosis.


Assuntos
Antagonistas de Receptores de Angiotensina , Reestenose Coronária , Intervenção Coronária Percutânea , Humanos , Reestenose Coronária/prevenção & controle , Antagonistas de Receptores de Angiotensina/uso terapêutico , Intervenção Coronária Percutânea/métodos , Stents/efeitos adversos , Oclusão de Enxerto Vascular/prevenção & controle
3.
Molecules ; 29(16)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39202947

RESUMO

A traditional phase transformation method is commonly used to prepare molecular imprinting membranes for selective separation. However, traditional molecularly imprinted polymers are mostly micron-sized particles, and the imprinting sites in their membrane are easily embedded, leading to a reduced adsorption capacity and decreased selectivity. In this study, an ultra-long nanowire with a diameter of about 15 nm was synthesized for the separation of artemisinin (ART), and its adsorption capacity was as high as 198.29 mg g-1 after imprinting polymerization. Molecular imprinting membranes were prepared, using polyvinylidene fluoride (PVDF), polyethersulfone (PES), and polysulfone (PSF) as the membrane matrix, for comparison. The average membrane pore size of PVDF-MIM was about 480 nm, and PVDF-MIM had the highest adsorption capacity (69 mg g-1) for ART. The optimal flow rate for PVDF-MIM's dynamic adsorption of ART was 7 mL min-1. Under this optimal flow rate, selectivity experiments were carried out to obtain the separation factor of PVDF-MIM (α = 8.37), which was much higher than the corresponding values of PES-MIM and PSF-MIM. In addition, the hydrophobicity and low flux of PES-MIM and PSF-MIM lead to higher non-specific adsorption. The hydrophobicity of PVDF-MIM is lower than that of PES-MIM and PSF-MIM, which greatly reduces the non-specific adsorption of the membrane, thus increasing the selectivity of the membranes. Therefore, the effective density of the imprinting sites in the pores and the membrane structure are the main factors determining the efficient separation of molecularly imprinted membranes.

4.
Opt Express ; 31(14): 23183-23197, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37475409

RESUMO

An algorithm is proposed for few-shot-learning (FSL) jointing modulation format identification (MFI) and optical signal-to-noise ratio (OSNR) estimation. The constellation diagrams of six widely-used modulation formats over a wide range of OSNR (10-40 dB) are obtained by a dual-polarization (DP) coherent detection system at 32 GBaud. We introduce auxiliary task to model-agnostic meta-learning (MAML) which makes the gradient of meta tasks decline faster in the direction of optimal target. Ablation experiments including multi-task model-agnostic meta-learning (MT-MAML), single-task model-agnostic meta-learning (ST-MAML) and adaptive multi-task learning (AMTL) are executed to train a data set with only 20 examples for each class. First, we discuss the impact from the number of shots and gradient descent steps for support set on the meta-learning based schemes to determine the best hyper parameters and conclude that the proposed method better captures the similarity between new and previous knowledge at 4 shot and 1 step. Withdrawn fine-tuning, the model achieves the lowest error ∼0.37 dB initially. Then, we simulate two other schemes (AMTL and ST-MAML), and the numerical results shows that mean square error (MSE) are ∼0.6 dB, ∼0.3 dB and ∼0.18 dB, respectively, proposed method has faster adaption to main task. For low order modulation formats, the proposed method almost reduces the error to 0. Meanwhile, we reveal the degree of deviation between the prediction and target and find that the deviation is mainly concentrated in the high OSNR range of 25-40 dB. Specifically, we investigate the variation curve of adaptive weights during pretraining and conclude that after 30 epoch, the model's attention was almost entirely focused on estimating OSNR. In addition, we study the generalization ability of the model by varying the transmission distance. Importantly, excellent generalization is also experimentally verified. In this paper, the method proposed will greatly reduce the cost for repetitively collecting data and the training resources required for fine-tuning models when OPM devices need to be deployed at massive nodes in dynamic optical networks.

5.
Pestic Biochem Physiol ; 196: 105619, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37945255

RESUMO

The insect olfaction plays crucial roles in many important behaviors, in which ORs are key determinants for signal transduction and the olfactory specificity. Spodoptera litura is a typical polyphagous pest, possessing a large repertoire of ORs tuning to broad range of plant odorants. However, the specific functions of those ORs remain mostly unknown. In this study, we functionally characterized one S. litura OR (OR51) that was highly expressed in the adult antennae. First, by using Xenopus oocyte expression and two-electrode voltage clamp recording system (XOE-TEVC), OR51 was found to be strongly and specifically responsive to vanillin (a volatile of S. litura host plants) among 77 tested odorants. Second, electroantennogram (EAG) and Y-tube behavioral experiment showed that vanillin elicited significant EAG response and attraction behavior especially of female adults. This female attraction was further confirmed by the oviposition experiment, in which the soybean plants treated with vanillin were significantly preferred by females for egg-laying. Third, 3D structural modelling and molecular docking were conducted to explore the interaction between OR51 and vanillin, which showed a high affinity (-4.46 kcal/mol) and three residues (Gln163, Phe164 and Ala305) forming hydrogen bonds with vanillin, supporting the specific binding of OR51 to vanillin. In addition, OR51 and its homologs from other seven noctuid species shared high amino acid identities (78-97%) and the same three hydrogen bond forming residues, suggesting a conserved function of the OR in these insects. Taken together, our study provides some new insights into the olfactory mechanisms of host plant finding and suggests potential applications of vanillin in S. litura control.


Assuntos
Receptores Odorantes , Animais , Feminino , Spodoptera/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Simulação de Acoplamento Molecular , Plantas/química , Proteínas de Insetos/metabolismo
6.
Sensors (Basel) ; 23(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37447828

RESUMO

Image dehazing based on convolutional neural networks has achieved significant success; however, there are still some problems, such as incomplete dehazing, color deviation, and loss of detailed information. To address these issues, in this study, we propose a multi-scale dehazing network with dark channel priors (MSDN-DCP). First, we introduce a feature extraction module (FEM), which effectively enhances the ability of feature extraction and correlation through a two-branch residual structure. Second, a feature fusion module (FFM) is devised to combine multi-scale features adaptively at different stages. Finally, we propose a dark channel refinement module (DCRM) that implements the dark channel prior theory to guide the network in learning the features of the hazy region, ultimately refining the feature map that the network extracted. We conduct experiments using the Haze4K dataset, and the achieved results include a peak signal-to-noise ratio of 29.57 dB and a structural similarity of 98.1%. The experimental results show that the MSDN-DCP can achieve superior dehazing compared to other algorithms in terms of objective metrics and visual perception.


Assuntos
Algoritmos , Benchmarking , Aprendizagem , Redes Neurais de Computação , Razão Sinal-Ruído
7.
BMC Cardiovasc Disord ; 22(1): 194, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35473672

RESUMO

BACKGROUND: COVID-19 affects healthcare resource allocation, which could lead to treatment delay and poor outcomes in patients with acute myocardial infarction (AMI). We assessed the impact of the COVID-19 pandemic on AMI outcomes. METHODS: We compared outcomes of patients admitted for acute ST-elevation MI (STEMI) and non-STEMI (NSTEMI) during a non-COVID-19 pandemic period (January-February 2019; Group 1, n = 254) and a COVID-19 pandemic period (January-February 2020; Group 2, n = 124). RESULTS: For STEMI patients, the median of first medical contact (FMC) time, door-to-balloon time, and total myocardial ischemia time were significantly longer in Group 2 patients (all p < 0.05). Primary percutaneous intervention was performed significantly more often in Group 1 patients than in Group 2 patients, whereas thrombolytic therapy was used significantly more often in Group 2 patients than in Group 1 patients (all p < 0.05). However, the rates of and all-cause 30-day mortality and major adverse cardiac event (MACE) were not significantly different in the two periods (all p > 0.05). For NSTEMI patients, Group 2 patients had a higher rate of conservative therapy, a lower rate of reperfusion therapy, and longer FMC times (all p < 0.05). All-cause 30-day mortality and MACE were only higher in NSTEMI patients during the COVID-19 pandemic period (p < 0.001). CONCLUSIONS: COVID-19 pandemic causes treatment delay in AMI patients and potentially leads to poor clinical outcome in NSTEMI patients. Thrombolytic therapy should be initiated without delay for STEMI when coronary intervention is not readily available; for NSTEMI patients, outcomes of invasive reperfusion were better than medical treatment.


Assuntos
COVID-19 , Infarto do Miocárdio , Infarto do Miocárdio sem Supradesnível do Segmento ST , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/terapia , Infarto do Miocárdio sem Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio sem Supradesnível do Segmento ST/terapia , Pandemias , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/epidemiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Fatores de Tempo , Resultado do Tratamento
8.
Molecules ; 27(23)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36500385

RESUMO

Mitochondria play a central role in the survival or death of neuronal cells, and they are regulators of energy metabolism and cell death pathways. Many studies support the role of mitochondrial dysfunction and oxidative damage in the pathogenesis of Alzheimer's disease. Biatractylolide (BD) is a kind of internal symmetry double sesquiterpene novel ester compound isolated from the Chinese medicinal plant Baizhu, has neuroprotective effects in Alzheimer's disease. We developed a systematic pharmacological model based on chemical pharmacokinetic and pharmacological data to identify potential compounds and targets of Baizhu. The neuroprotective effects of BD in PC12 (rat adrenal pheochromocytoma cells) and SH-SY5Y (human bone marrow neuroblastoma cells) were evaluated by in vitro experiments. Based on the predicted results, we selected 18 active compounds, which were associated with 20 potential targets and 22 signaling pathways. Compound-target, target-disease and target-pathway networks were constructed using Cytoscape 3.2.1. And verified by in vitro experiments that BD could inhibit Aß by reducing oxidative stress and decreasing CytC release induced mPTP opening. This study provides a theoretical basis for the development of BD as an anti-Alzheimer's disease drug.


Assuntos
Doença de Alzheimer , Neuroblastoma , Fármacos Neuroprotetores , Humanos , Ratos , Animais , Fármacos Neuroprotetores/química , Apoptose , Linhagem Celular Tumoral , Neuroblastoma/tratamento farmacológico , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo
9.
Small ; 17(31): e2100479, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34173330

RESUMO

Local minimally invasive injection of anticancer therapies is a compelling approach to maximize the utilization of drugs and reduce the systemic adverse drug effects. However, the clinical translation is still hampered by many challenges such as short residence time of therapeutic agents and the difficulty in achieving multi-modulation combination therapy. Herein, mesoporous silica-coated gold nanorods (AuNR@SiO2 ) core-shell nanoparticles are fabricated to facilitate drug loading while rendering them photothermally responsive. Subsequently, AuNR@SiO2 is anchored into a monodisperse photocrosslinkable gelatin (GelMA) microgel through one-step microfluidic technology. Chemotherapeutic drug doxorubicin (DOX) is loaded into AuNR@SiO2 and 5,6-dimethylxanthenone-4-acetic acid (DMXAA) is loaded in the microgel layer. The osteosarcoma targeting ligand alendronate is conjugated to AuNR@SiO2 to improve the tumor targeting. The microgel greatly improves the injectability since they can be dispersed in buffer and the injectability and degradability are adjustable by microfluidics during the fabrication. The drug release can, in turn, be modulated by multi-round light-trigger. Importantly, a single super low drug dose (1 mg kg-1 DOX with 5 mg kg-1 DMXAA) with peritumoral injection generates long-term therapeutic effect and significantly inhibited tumor growth in osteosarcoma bearing mice. Therefore, this nanocomposite@microgel system can act as a peritumoral reservoir for long-term effective osteosarcoma treatment.


Assuntos
Microgéis , Nanopartículas , Nanotubos , Osteossarcoma , Animais , Doxorrubicina , Ouro , Camundongos , Osteossarcoma/tratamento farmacológico , Dióxido de Silício
10.
J Clean Prod ; 279: 123431, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32836912

RESUMO

Currently, the "2019-CoV-2" has been raging across the world for months, causing massive death, huge panic, chaos, and immeasurable economic loss. Such emerging epidemic viruses come again and again over years, leading to similar destructive consequences. Air-borne transmission among humans is the main reason for the rapid spreading of the virus. Blocking the air-borne transmission should be a significant measure to suppress the spreading of the pandemic. Considering the hospital is the most probable place to occur massive cross-infection among patients as emerging virus usually comes in a disguised way, an air distribution optimization of a general three-bed hospital ward in China is carried out in this paper. Using the Eulerian-Lagrangian method, sneeze process from patients who are assumed to be the virus carrier, which is responsible for a common event to trigger cross-infection, is simulated. The trajectory of the released toxic particle and the probability of approaching others in the same ward are calculated. Two evaluation parameter, total maximum time (TMT) and overall particle concentration (OPC) to reflect the particle mobility and probability to cause cross-infection respectively, are developed to evaluate the proposed ten air distributions in this paper. A relatively optimized air distribution proposal with the lowest TMT and OPC is distinguished through a three-stage analysis. Results show that a bottom-in and top-out air distribution proposal is recommended to minimize cross-infections.

11.
Small ; 16(27): e1906644, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32101378

RESUMO

Billions of dollars are invested into the monoclonal antibody market every year to meet the increasing demand in clinical diagnosis and therapy. However, natural antibodies still suffer from poor stability and high cost, as well as ethical issues in animal experiments. Thus, developing antibody substitutes or mimics is a long-term goal for scientists. The molecular imprinting technique presents one of the most promising strategies for antibody mimicking. The molecularly imprinted polymers (MIPs) are also called "molecularly imprinted synthetic antibodies" (MISAs). The breakthroughs of key technologies and innovations in chemistry and material science in the last decades have led to the rapid development of MISAs, and their molecular affinity has become comparable to that of natural antibodies. Currently, MISAs are undergoing a revolutionary transformation of their applications, from initial adsorption and separation to the rising fields of biomedicine. Herein, the fundamental chemical design of MISAs is examined, and then current progress in biomedical applications is the focus. Meanwhile, the potential of MISAs as qualified substitutes or even to transcend the performance of natural antibodies is discussed from the perspective of frontier needs in biomedicines, to facilitate the rapid development of synthetic artificial antibodies.


Assuntos
Anticorpos , Tecnologia Biomédica , Polímeros Molecularmente Impressos , Animais , Anticorpos/química , Tecnologia Biomédica/tendências , Polímeros Molecularmente Impressos/química , Polímeros Molecularmente Impressos/uso terapêutico
12.
Small ; 15(1): e1803913, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30468558

RESUMO

Paper-based assays for detection of physiologically important species are needed in medical theranostics owning to their superiorities in point of care testing, daily monitoring, and even visual readout by using chromogenic materials. In this work, a facile test strip is developed for visual detection of a neurotransmitter dopamine (DA) based on dual-emission fluorescent molecularly imprinted polymer nanoparticles (DE-MIPs). The DE-MIPs, featured with tailor-made DA affinity and good anti-interference, exhibit DA concentration-dependent fluorescent colors, due to the variable ratios of dual-emission fluorescence caused by DA binding and quenching. By facile coating DE-MIPs on a filter paper, the DA test strips are obtained. The resultant test strip, like the simplicity of a pH test paper, shows the potential for directly visual detection of DA levels just by dripping a tiny amount of biofluid sample on it. The test result of real serum samples demonstrates that the DA strip enables to visually and semiquantitatively detect DA within 3 min by using only 10 µL of serum samples and with a low detection limit ((100-150) × 10-9 m) by naked eye. This work thus offers a facile and efficient strategy for rapid, visual, and on-site detection of biofluids in clinic.


Assuntos
Líquidos Corporais/química , Dopamina/análise , Impressão Molecular , Dopamina/sangue , Humanos , Pontos Quânticos/ultraestrutura , Espectrometria de Fluorescência
13.
Heart Vessels ; 34(7): 1230-1239, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30671641

RESUMO

We established a rabbit iliac artery restenosis model to explore the impact of Telmisartan on the expression of Connexin43 (Cx43) and neointimal hyperplasia. Thirty New Zealand white rabbits were randomly divided into three groups: control group (n = 10), restenosis group (n = 10), and Telmisartan group (n = 10). The restenosis model was established by high-cholesterol diet combined with double-balloon injury of iliac arteries. In addition, Telmisartan at 5 mg/(kg day) was administered to the rabbits of Telmisartan group on the second day after the second balloon injury. All rabbits were killed at the end of the experiment followed by institution policy. Before sacrifice, blood samples were obtained to test serum angiotensinII (AngII). Iliac arteries were isolated for morphological analysis and determining the expression of Cx43 by HE staining, immunohistochemical analysis, reverse transcription-polymerase chain reaction (RT-PCR), and Western Blotting analysis. Then, the local AngII levels of arteries were measured by radioimmunoassay. As compared with controls, the expression of Cx43 mRNA (0.98 ± 0.08) vs. (1.27 ± 0.17), P < 0.01), and Cx43 protein [(0.75 ± 0.08) vs. (0.90 ± 0.08), P < 0.05] of restenosis group were increased, which were significantly higher than those of Telmisartan group [Cx43 mRNA: (1.27 ± 0.17) vs. (1.00 ± 0.20), P < 0.01; Cx43 protein: (0.90 ± 0.08) vs. (0.82 ± 0.05), P < 0.05]. Furthermore, The intima thickness [(266.12 ± 70.27) vs. (2.85 ± 0.19) µm, P < 0.01] and the local AngII [(115.6 ± 15.7) vs. (90.1 ± 7.7), P < 0.05] of restenosis group were raised when compared with controls. Telmisartan group exhibited thinner intima compared with restenosis group [(68.22 ± 24.37) vs. (266.12 ± 70.27), P < 0.01]. However, the local AngII levels between these two groups were approximate. In addition, the plasma concentration of AngII was not significantly different among three groups. In conclusion, Telmisartan can inhibit the expression of connexin43 and neointimal hyperplasia in iliac artery restenosis model.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Conexina 43/metabolismo , Artéria Ilíaca/lesões , Telmisartan/farmacologia , Animais , Cateterismo , Proliferação de Células/efeitos dos fármacos , Conexina 43/genética , Hiperplasia/prevenção & controle , Artéria Ilíaca/patologia , Masculino , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/citologia , Neointima/prevenção & controle , Coelhos
14.
Entropy (Basel) ; 21(3)2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33266938

RESUMO

The aerospace-based heat sink is defined as a substance used for dissipating heat generated by onboard heat loads. They are becoming increasingly scarce in the thermal management system (TMS) of advanced aircraft, especially for supersonic aircraft. In the modern aircraft there are many types of heat sinks whose cooling abilities and performance penalties are usually obviously different from each other. Besides, the cooling ability and performance penalty of a single heat sink is even different under different flight conditions-flight altitude, Mach number, etc. In this study, the typical heat sinks which are the fuel mass, ram air, engine fan air, skin heat exchanger, and expendable heat sink will be studied. Their cooling abilities/capacities, and exergy penalties under different flight conditions have been systematically estimated and compared with each other. The exergy penalty presented in this paper refers to the exergy loss of aircraft caused by the extra weight, drag and energy extraction of various heat sinks. The estimation models, as well as the results and discussion have been elaborated in this paper, which can be can be used to further optimize the TMS of modern advanced aircraft, for example, the layout design of various heat sinks and the improvement the control algorithm.

15.
Entropy (Basel) ; 21(4)2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33267134

RESUMO

This paper presents a nanofluid-based cooling method for a brushless synchronous generator (BLSG) by using Al2O3 lubricating oil. In order to demonstrate the superiority of the nanofluid-based cooling method, analysis of the thermal performance and efficiency of the nanofluid-based cooling system (NBCS) for the BLSG is conducted along with the modeling and simulation cases arranged for NBCS. Compared with the results obtained under the base fluid cooling condition, results show that the nanofluid-based cooling method can reduce the steady-state temperature and power losses in BLSG and decrease the temperature settling time and changing ratio, which demonstrate that both steady-state and transient thermal performance of NBCS are improved as nanoparticle volume fraction (NVF) in nanofluid increases. Besides, although the input power of cycling pumps in NBCS has ~30% increase when the NVF is 10%, the efficiency of the NBCS has a slight increase because the 4.1% reduction in power loss of BLSG is bigger than the total incensement of input power of the cycling pumps. The results illustrate the superiority of the nanofluid-based cooling method, and it indicates that the proposed method has a broad application prospect in the field of thermal control of onboard synchronous generators with high power density.

16.
Entropy (Basel) ; 21(6)2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33267292

RESUMO

A proper operating temperature range and an acceptable temperature uniformity are extremely essential for the efficient and safe operation of the Li-ion battery array, which is an important power source of space stations. The single-phase fluid loop is one of the effective approaches for the thermal management of the battery. Due to the limitation that once the structure of the cold plate (CP) is determined, it is difficult to adjust the cooling ability of different locations of the CP dynamically, this may lead to a large temperature difference of the battery array that is attached to the different locations of the CP. This paper presents a micro-channel CP integrated with a thermoelectric heat pump (THP) in order to achieve the dynamic adjustment of the cooling ability of different locations of the CP. The THP functions to balance the heat transfer within the CP, which transports the heat of the high-temperature region to the low-temperature region by regulating the THP current, where a better temperature uniformity of the CP can be achieved. A lumped-parameter model for the proposed system is established to examine the effects of the thermal load and electric current on the dynamic thermal characteristics. In addition, three different thermal control algorithms (basic PID, fuzzy-PID, and BP-PID) are explored to examine the CP's temperature uniformity performance by adapting the electric current of the THP. The results demonstrate that the temperature difference of the focused CP can be declined by 1.8 K with the assistance of the THP. The proposed fuzzy-PID controller and BP-PID controller present much better performances than that provided by the basic PID controller in terms of overshoot, response time, and steady state error. Such an innovative arrangement will enhance the CP's dynamic cooling ability distribution effectively, and thus improve the temperature uniformity and operating reliability of the Li-ion space battery array further.

17.
BMC Cardiovasc Disord ; 18(1): 233, 2018 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-30541457

RESUMO

BACKGROUND: Plaque composition and morphologic characteristics identified by virtual histology intravascular ultrasound (VH-IVUS) can determine plaques at increased risk of clinical events following percutaneous coronary intervention (PCI) among coronary artery disease (CAD) patients. However, there have been few studies to investigate the relationship between plaque composition of saphenous vein graft (SVG) by VH-IVUS and clinical outcomes in patients with saphenous vein graft disease (SVGD) undergoing PCI. The purpose of this study is to determine whether plaque components and characteristics by VH-IVUS can predict major adverse cardiac events (MACEs) among SVGD patients undergoing PCI. METHODS/DESIGN: This is a prospective cohort study conducted in Tianjin Chest Hospital, China. Participants with SVGD referred for PCI will be invited to participate in this study, and will be followed up at 1, 6, 12, 24 and 36 months post-PCI to assess clinical outcomes. The planned sample size is 175 subjects. We will recruit subjects with SVGD scheduled to receive PCI, aged 18-80 years, with a history of previous coronary artery bypass graft (CABG) surgery more than 1 year ago, and willing to participate in the study and sign informed consent. The composite primary study endpoint is the incidence of MACEs after PCI for SVGD, including death from cardiac causes, non-fatal myocardial infarction, unplanned target lesion revascularization (TLR) and target vessel revascularization (TVR). The primary outcome analysis will be presented as Kaplan-Meier estimates and the primary outcome analysis will be carried out using a Cox proportional hazards regression model. DISCUSSION: Once the predictive values of plaque components and characteristics by VH-IVUS on subsequent clinical outcomes are determined among SVGD patients undergoing PCI, an innovative prediction tool of clinical outcomes for SVGD patients undergoing PCI will be created, which may lead to the development of new methods of risk stratification and intervention guidance. TRIAL REGISTRATION: The study is registered to ClinicalTrials.gov (NCT03175952).


Assuntos
Ponte de Artéria Coronária/efeitos adversos , Oclusão de Enxerto Vascular/cirurgia , Intervenção Coronária Percutânea , Placa Aterosclerótica , Projetos de Pesquisa , Veia Safena/transplante , Ultrassonografia de Intervenção , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Ponte de Artéria Coronária/mortalidade , Feminino , Oclusão de Enxerto Vascular/diagnóstico por imagem , Oclusão de Enxerto Vascular/mortalidade , Oclusão de Enxerto Vascular/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Veia Safena/diagnóstico por imagem , Veia Safena/patologia , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
18.
J Sep Sci ; 41(8): 1880-1887, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29389060

RESUMO

An imprinted fluorescent sensor was fabricated based on SiO2 nanoparticles encapsulated with a molecularly imprinted polymer containing allyl fluorescein. High fluorine cypermethirin as template molecules, methyl methacrylate as functional monomer, and allyl fluorescein as optical materials synthesized a core-shell fluorescent molecular imprinted sensor, which showed a high and rapid sensitivity and selectivity for the detection of τ-fluvalinate. The sensor presented appreciable sensitivity with a limit of 13.251 nM, rapid detection that reached to equilibrium within 3 min, great linear relationship in the relevant concentration range from 0 to 150 nM, and excellent selectivity over structural analogues. In addition, the fluorescent sensor demonstrated desirable regeneration ability (eight cycling operations). The molecularly imprinted polymers ensured specificity, while the fluorescent dyes provided the stabile sensitivity. Finally, an effective application of the sensor was implemented by the detection of τ-fluvalinate in real samples from vodka. The molecularly imprinted fluorescent sensor showed a promising potential in environmental monitoring and food safety.


Assuntos
Bebidas Alcoólicas/análise , Corantes Fluorescentes/química , Impressão Molecular , Nanocompostos/química , Nitrilas/análise , Piretrinas/análise , Dióxido de Silício/química , Corantes Fluorescentes/síntese química , Estrutura Molecular
19.
J Sep Sci ; 41(19): 3782-3790, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30070767

RESUMO

Fluorescent molecularly imprinted nanoparticles have shown great promise in the field of chemical analysis or detection because of their high stability, selectivity, and sensitivity. In this work, fluorescent molecularly imprinted nanoparticles were synthesized by precipitation polymerization employing fluorescein isothiocyanate as luminescent material, which could efficiently and rapidly detect ciprofloxacin in water samples. The prepared fluorescent molecularly imprinted nanoparticles had remarkable stability and good selectivity with the method detection limit low to 4.04 nm. In addition, the fluorescent-imprinted nanoparticles were capable of identifying the target with high detection efficiency and were applied to the detection of ciprofloxacin in aquaculture water with complex composition. All these would provide the direct monitoring of ciprofloxacin in environmental water with a promising fluorescent imprinting strategy.


Assuntos
Aquicultura , Ciprofloxacina/análise , Fluorescência , Corantes Fluorescentes/química , Impressão Molecular , Nanopartículas/química , Poluentes Químicos da Água/química , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
20.
Med Sci Monit ; 23: 2465-2469, 2017 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-28534476

RESUMO

BACKGROUND To explore the significance of short message service (SMS) on the management of pulmonary tuberculosis (TB) patients in reinforcing the treatment adherence and health awareness, and provide scientific evidences for popularizing this model and formulating related polices and measures. MATERIAL AND METHODS Six counties (districts) were selected by stratified cluster sampling method, and randomly divided into control group and intervention group. Pulmonary TB patients eligible to the study criteria were included in the study. SMS management and regular education of core knowledge about pulmonary TB were carried out in SMS group patients. The conventional directly observed therapy (DOT) was carried out in control group. Data was collected by questionnaire method. RESULTS A total of 350 patients were included in the study, including 160 cases in the SMS group and 190 cases in the control group. There were 270 males (77.1%) and 80 females (22.9%). The treatment completion rate in SMS group (96.25%) was significantly higher than that in the control group (86.84%) (χ²=9.52, P=0.002). Both the interrupted treatment rate and the missed dose rate in the SMS group were significantly lower than those in the control group (χ²=10.41, P=0.001; χ²=28.54, P<0.001). After a period of treatment, the reexamination rate of SMS group patients was significantly higher than that in control group (except the reexamination rate after 5 months treatment). CONCLUSIONS The management of pulmonary TB patients by SMS can effectively reinforce the completed treatment rate of pulmonary TB patients and reduce their missed dose rate and interrupted treatment rate, and further enhance their reexamination awareness. Therefore, SMS on the management of patients may be a new promising therapeutic strategy for pulmonary TB.


Assuntos
Envio de Mensagens de Texto , Tuberculose Pulmonar/terapia , Adulto , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Cooperação e Adesão ao Tratamento
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