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1.
Nano Lett ; 23(22): 10317-10325, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37937967

RESUMO

Thin film-based thermal flow sensors afford applications in healthcare and industries owing to their merits in preserving initial flow distributions. However, traditional thermal flow sensors are primarily applied to track flow intensities based on hot-wire or hot-film sensing mechanisms due to their relatively facile device configurations and fabrication strategies. Herein, a calorimetric thermal flow sensor is proposed based on laser direct writing to form laser-induced graphene as heaters and temperature sensors, resulting in monitoring both flow intensities and orientations. Via homogeneously surrounding spiral heaters with multiple temperature sensors, the device exhibits high sensitivity (∼162 K·s/m) at small flows with an extended flow detection range (∼25 m/s). Integrating the device with a data-acquisition board and a dual-mode graphical user interface enables wirelessly and dynamically monitoring respiration and the motion of robotic arms. This versatile flow sensor with facile manufacturing affords potentials in health inspection, remote monitoring, and studying hydrodynamics.

2.
J Biol Chem ; 298(12): 102630, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36273585

RESUMO

Breast cancer is the most prevalent cancer among women, and it is characterized by a high rate of tumor development and heterogeneity. Breast cancer stem cells (CSCs) may well contribute to these pathological properties, but the mechanisms underlying their self-renewal and maintenance are still elusive. Here, we found that the long noncoding RNA HOTAIR is highly expressed in breast CSCs. HOTAIR is required for breast CSC self-renewal and tumor propagation. Mechanistically, we demonstrate that HOTAIR recruits the PRC2 protein complex to the promoter of IκBα to inhibit its expression, leading to activation of the NF-κB signaling pathway. The activated NF-κB signaling promotes downstream c-Myc and Cyclin D1 expression. Furthermore, our analysis of clinical samples from the GEPIA database indicated that the IκBα level, as well as the survival rate of patients, with high HOTAIR expression was significantly lower than that of patients with relatively low HOTAIR expression. Our data suggest that HOTAIR-mediated NF-κB signaling primes breast CSC self-renewal and tumor propagation. In sum, we have identified HOTAIR-based NF-κB signaling regulatory circuit that promotes tumorigenic activity in breast CSCs, further indicating that HOTAIR could be a promising target for clinical treatment of breast cancers.


Assuntos
Neoplasias da Mama , RNA Longo não Codificante , Transdução de Sinais , Feminino , Humanos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , NF-kappa B/genética , NF-kappa B/metabolismo , Inibidor de NF-kappaB alfa/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Células-Tronco Neoplásicas/metabolismo
3.
Small ; 19(49): e2304370, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37587781

RESUMO

Reprogramming the immunologically "cold" environment of solid tumors is currently becoming the mainstream strategy to elicit powerful and systemic anticancer immunity. Here, a facile and biomimetic nano-immunnoactivator (CuS/Z@M4T1 ) is detailed by engineering a Zn2+ -bonded zeolitic imidazolate framework-8 (ZIF-8) with CuS nanodots (NDs) and cancer cell membrane for amplified near-infrared-II (NIR-II) photothermal immunotherapy via Zn2+ metabolic modulation. Taking advantage of the NIR-II photothermal effect of CuS NDs and the acidic responsiveness of ZIF-8, CuS/Z@M4T1 rapidly causes intracellular Zn2+ pool overload and disturbs the metabolic flux of 4T1 cells, which effectively hamper the production of heat shock proteins and relieve the resistance of photothermal therapy (PTT). Thus, amplified immunogenic cell death is evoked and initiates the immune cascade both in vivo and in vitro as demonstrated by dendritic cells maturation and T-cell infiltration. Further combination with antiprogrammed death 1 (aPD-1) achieves escalated antitumor efficacy which eliminates the primary, distant tumor and avidly inhibits lung metastasis due to cooperation of enhanced photothermal stimulation and empowerment of cytotoxic T lymphocytes by aPD-1. Collectively, this work provides the first report of using the intrinsic modulation property of meta-organometallic ZIF-8 for enhanced cancer photoimmunotherapy together with aPD-1, thereby inspiring a novel combined paradigm of ion-rich nanomaterials for cancer treatment.


Assuntos
Nanopartículas , Neoplasias , Humanos , Adjuvantes Imunológicos , Biomimética , Fototerapia , Neoplasias/terapia , Imunoterapia , Linhagem Celular Tumoral
4.
Arch Virol ; 168(12): 301, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38019293

RESUMO

The "Shock and Kill" method is being considered as a potential treatment for eradicating HIV-1 and achieving a functional cure for acquired immunodeficiency syndrome (AIDS). This approach involves using latency-reversing agents (LRAs) to activate human immunodeficiency virus (HIV-1) transcription in latent cells, followed by treatment with antiviral drugs to kill these cells. Although LRAs have shown promise in HIV-1 patient research, their widespread clinical use is hindered by side effects and limitations. In this review, we categorize and explain the mechanisms of these agonists in activating HIV-1 in vivo and discuss their advantages and disadvantages. In the future, combining different HIV-1 LRAs may overcome their respective shortcomings and facilitate a functional cure for HIV-1.


Assuntos
Síndrome da Imunodeficiência Adquirida , HIV-1 , Humanos , Antivirais
5.
Cell Biochem Funct ; 41(8): 1106-1114, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38041420

RESUMO

The N-methyladenosine (m6A) modification of ribosomal RNA (rRNA) plays critical roles in regulating the function of ribosomes, the essential molecular machines that translate genetic information from mRNA into proteins. Specifically, m6A modification affects ribosome biogenesis, stability, and function by regulating the processing and maturation of rRNA, the assembly and composition of ribosomes, and the accuracy and efficiency of translation. Furthermore, m6A modification allows for dynamic regulation of translation in response to environmental and cellular signals. Therefore, a deeper understanding of the mechanisms and functions of m6A modification in rRNA will advance our knowledge of ribosome-mediated gene expression and facilitate the development of new therapeutic strategies for ribosome-related diseases.


Assuntos
RNA Ribossômico , Ribossomos , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , Ribossomos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Metilação
6.
J Nanobiotechnology ; 21(1): 186, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37301952

RESUMO

Targeted chemo-phototherapy has received widespread attention in cancer treatment for its advantages in reducing the side effects of chemotherapeutics and improving therapeutic effects. However, safe and efficient targeted-delivery of therapeutic agents remains a major obstacle. Herein, we successfully constructed an AS1411-functionalized triangle DNA origami (TOA) to codeliver chemotherapeutic drug (doxorubicin, DOX) and a photosensitizer (indocyanine green, ICG), denoted as TOADI (DOX/ICG-loaded TOA), for targeted synergistic chemo-phototherapy. In vitro studies show that AS1411 as an aptamer of nucleolin efficiently enhances the nanocarrier's endocytosis more than 3 times by tumor cells highly expressing nucleolin. Subsequently, TOADI controllably releases the DOX into the nucleus through the photothermal effect of ICG triggered by near-infrared (NIR) laser irradiation, and the acidic environment of lysosomes/endosomes facilitates the release. The downregulated Bcl-2 and upregulated Bax, Cyt c, and cleaved caspase-3 indicate that the synergistic chemo-phototherapeutic effect of TOADI induces the apoptosis of 4T1 cells, causing ~ 80% cell death. In 4T1 tumor-bearing mice, TOADI exhibits 2.5-fold targeted accumulation in tumor region than TODI without AS1411, and 4-fold higher than free ICG, demonstrating its excellent tumor targeting ability in vivo. With the synergetic treatment of DOX and ICG, TOADI shows a significant therapeutic effect of ~ 90% inhibition of tumor growth with negligible systemic toxicity. In addition, TOADI presents outstanding superiority in fluorescence and photothermal imaging. Taken together, this multifunctional DNA origami-based nanosystem with the advantages of specific tumor targeting and controllable drug release provides a new strategy for enhanced cancer therapy.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Animais , Camundongos , Sistemas de Liberação de Medicamentos/métodos , Hipertermia Induzida/métodos , Fototerapia/métodos , Doxorrubicina , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , DNA/uso terapêutico , Concentração de Íons de Hidrogênio , Nanopartículas/uso terapêutico , Liberação Controlada de Fármacos , Linhagem Celular Tumoral
7.
Mediators Inflamm ; 2022: 1153300, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262548

RESUMO

Regulatory T cells (Tregs) and M2c macrophages have been shown to exert potentially synergistic therapeutic effects in animals with adriamycin-induced nephropathy (AN), a model chronic proteinuric renal disease. M2c macrophages may protect against renal injury by promoting an increase in the number of Tregs in the renal draining lymph nodes of AN mice, but how they do so is unclear. In this study, we used an AN mouse model to analyze how M2c macrophages induce the migration of Tregs. Using flow cytometry, we found that M2c macrophages promoted the migration of Tregs from the peripheral blood to the spleen, thymus, kidney, and renal draining lymph nodes. At the same time, M2c macrophages significantly upregulated chemokine receptors and adhesion molecule in Tregs, including CCR4, CCR5, CCR7, CXCR5, and CD62L. Treating AN mice with monoclonal anti-CD62L antibody inhibited the migration of M2c macrophages and Tregs to the spleen, thymus, kidney, and renal draining lymph nodes. Taken together, our results suggest that M2c macrophages upregulate CD62L in Tregs and thereby promote their migration to inflammatory sites, where they exert renoprotective effects. These insights may aid the development of treatments against chronic kidney disease.


Assuntos
Doxorrubicina , Insuficiência Renal Crônica , Camundongos , Animais , Doxorrubicina/toxicidade , Receptores CCR7 , Macrófagos , Linfócitos T Reguladores , Insuficiência Renal Crônica/patologia
8.
Environ Res ; 202: 111664, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34256073

RESUMO

Eutrophication promotes massive cyanobacteria blooms (CBBs), leading to the release of volatile organic compounds (VOCs). To investigate the effects of cyanobacteria on VOC emissions, field campaigns were carried out in eutrophic Chaohu Lake at six sites with different microalgae densities during CBBs in summer 2019, and incubation experiments were performed in the laboratory. The results showed that the lake water was the primary source of VOCs at six sampling sites in Chaohu Lake during CBBs, with an average total VOC flux of 81.2 ± 20.6 µg m-2 h-1. Alkanes were the most abundantly emitted VOCs, with a share of 23.1-63.7% of total emitted VOCs, followed by aromatics (16.6-46.3%). The fluxes of total VOCs were significantly greater at sites B and/or C than at site A in July, and at site B' and/or C' than at site A' in August in Chaohu Lake. The fluxes of total VOCs from living and decayed cyanobacteria in the experimental treatments were two orders of magnitude higher than the corresponding values in the control treatments in the laboratory incubation. Taken together, these results suggested that CBBs potentially enhanced VOC emissions from the eutrophic lake, and that cyanobacteria acted as an important source of VOCs. Additionally, non-methane hydrocarbons (i.e., alkanes, alkenes, and aromatics) predominated among the released VOCs during the stabilization and senescence stages, while oxygenated volatile organic compounds (i.e. alcohols, aldehydes, ketones, esters, and furans) prevailed during the apoptosis stage and aromatics and volatile organic sulfur compounds predominated during the decomposition stage, suggesting that VOC emissions varied markedly at different life stages.


Assuntos
Poluentes Atmosféricos , Cianobactérias , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Eutrofização , Hidrocarbonetos/análise , Lagos , Compostos Orgânicos Voláteis/análise
9.
Environ Monit Assess ; 193(7): 392, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34101032

RESUMO

In order to obtain the typical soil physical properties of reclaimed land more quickly and accurately, the South Dump of the China Coal's Antaibao Open-Pit Mine in Pingshuo was focussed on in this paper, and ground penetrating radar (GPR) technology was utilized to detect the soil physical properties of reclaimed land in the mining area. The soil profile sampling and GPR detection methods were used to acquire the data. The gravel content of surface soil was analyzed by counting the number of isolated gravel signals in GPR images. The change of effective soil thickness was analyzed by establishing the fitting relationship between calibration depth and GPR image depth. The Topp's model was validated by comparing its inversion with the measured soil volumetric water content. And the Topp's model was further validated by the soil volumetric water content obtained from the Topp's model and which obtained from the wave velocity inversion. The results are as follows: (1) Based on the number of isolated gravel signals in GPR images, we could qualitatively analyze the gravel content of surface soil reclaimed in the mining area. As the number of isolated gravel signals was greater, the gravel content of the surface soil was higher. (2) Using the known relative permittivity, electromagnetic wave velocity, and soil volumetric water content, the calibration depth and the reflection depth of the target (calibrator) of the GPR images were segmented, and the correlation between them is high. The fitting relationship (R2) of each segment was higher than 0.940, and the average value of the five-segment R2 was 0.966, which indicated more accurate detection of the effective soil thickness of the reclaimed land in the mining area. (3) GPR could be used to detect the soil volumetric water content of reclaimed land in mining area, and Topp's model was used for calculation of soil volumetric water content. The average deviation rate between the values from Topp's model and the measured values was 12%, and the average absolute value of the difference was 2%. In summary, the benefits of using GPR to detect soil physical properties of reclaimed land in mining area are as follows: (1) GPR can be used to detect soil layer thickness and surface gravel content faster and more accurately. (2) Topp model can also be used to calculate the soil moisture content of non-natural deposits such as reclaimed land in mining area.


Assuntos
Radar , Solo , China , Monitoramento Ambiental , Estudos de Viabilidade , Mineração
10.
Molecules ; 25(5)2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32110923

RESUMO

Current wound dressings have poor antimicrobial activities and are difficult to degrade. Therefore, biodegradable and antibacterial dressings are urgently needed. In this article, we used the hydrothermal method and side-by-side electrospinning technology to prepare a gelatin mat with incorporated zinc oxide/graphene oxide (ZnO/GO) nanocomposites. The resultant fibers were characterized by field emission environment scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffractometry (XRD) and Fourier transform infrared spectroscopy (FTIR). Results indicated that the gelatin fibers had good morphology, and ZnO/GO nanocomposites were uniformly dispersed on the fibers. The loss of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) viability were observed to more than 90% with the incorporation of ZnO/GO. The degradation process showed that the composite fibers completely degraded within 7 days and had good controllable degradation characteristics. This study demonstrated the potential applicability of ZnO/GO-gelatin mats with excellent antibacterial properties as wound dressing material.


Assuntos
Antibacterianos/farmacologia , Gelatina/síntese química , Grafite/química , Óxido de Zinco/química , Escherichia coli/efeitos dos fármacos , Gelatina/química , Gelatina/ultraestrutura , Testes de Sensibilidade Microbiana , Nanocompostos/química , Nanocompostos/ultraestrutura , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Termogravimetria , Difração de Raios X
12.
Sensors (Basel) ; 19(23)2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31783618

RESUMO

Gait analysis is an important assessment tool for analyzing vital signals collected from individuals and for providing physical information of the human body, and it is emerging in a diverse range of application scenarios, such as disease diagnosis, fall prevention, rehabilitation, and human-robot interaction. Herein, a kind of surface processed conductive rubber was designed and investigated to develop a pressure-sensitive insole to monitor planar pressure in a real-time manner. Due to a novel surface processing method, the pressure sensor was characterized by stable contact resistance, simple manufacturing, and high mechanical durability. In the experiments, it was demonstrated that the developed pressure sensors were easily assembled with the inkjet-printed electrodes and a flexible substrate as a pressure-sensitive insole while maintaining good sensing performance. Moreover, resistive signals were wirelessly transmitted to computers in real time. By analyzing sampled resistive data combined with the gait information monitored by a visual-based reference system based on machine learning method (k-Nearest Neighbor algorithm), the corresponding relationship between plantar pressure distribution and lower limb joint angles was obtained. Finally, the experimental validation of the ability to accurately divide gait into several phases was conducted, illustrating the potential application of the developed device in healthcare and robotics.

13.
Sensors (Basel) ; 18(11)2018 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-30413068

RESUMO

The existing public key-based en-route filtering schemes are vulnerable to report disruption attacks or selective forwarding attacks, and they fail to consider any measure to detect and punish the malicious nodes. The authors propose a series of public key-based security mechanisms for wireless sensor networks (WSNs) in this paper, including a mechanism for verifying the partial signatures, a substitution mechanism, an effective report forwarding protocol, and a trust value-based mechanism to identify and punish the malicious nodes. Finally, the authors develop a public key-based authentication and en-route filtering scheme (PKAEF), which can resist false data injection attacks, report disruption attacks and selective forwarding attacks, and can mitigate the impact of malicious nodes. Detailed performance analysis and evaluation show that, in most cases, PKAEF outperforms previous works in terms of safety, filtering efficiency, and data availability.

14.
J Fluoresc ; 27(5): 1721-1727, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28497408

RESUMO

One novel turn-on fluorescence probe founded on conjugated pyrazole Schiff base for detecting Al3+ was invented. The UV-vis and fluorescence spectrometer were employed to explore optical properties of this probe. The results got from those experiments indicated that this fluorescence probe manifested excellent sensitivity and selectivity for Al3+ compared with other cations examined(Ag+, Co2+, Mg2+, Cu2+, Ni2+, Pb2+,and Zn2+). In addition, this probe displayed a more rapid response and remained stable between pH 6 and 9 by investigating the fluorescence intensity under different response time and various pH values. Remarkably, the detection limit for Al3+ could lower to 1.0×10-9M. Therefore, the probe could be potentially applied to the environment for the detection of Al3+, and the availability in biological range of pH that could be further studied to make this probe apply to biological systems in the future.

15.
Sensors (Basel) ; 16(2): 259, 2016 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-26907293

RESUMO

In recent years, we have seen many applications of secure query in two-tiered wireless sensor networks. Storage nodes are responsible for storing data from nearby sensor nodes and answering queries from Sink. It is critical to protect data security from a compromised storage node. In this paper, the Communication-efficient Secure Range Query (CSRQ)-a privacy and integrity preserving range query protocol-is proposed to prevent attackers from gaining information of both data collected by sensor nodes and queries issued by Sink. To preserve privacy and integrity, in addition to employing the encoding mechanisms, a novel data structure called encrypted constraint chain is proposed, which embeds the information of integrity verification. Sink can use this encrypted constraint chain to verify the query result. The performance evaluation shows that CSRQ has lower communication cost than the current range query protocols.

16.
Zhonghua Yi Xue Za Zhi ; 95(11): 836-40, 2015 Mar 24.
Artigo em Zh | MEDLINE | ID: mdl-26080916

RESUMO

OBJECTIVE: To explore the predictive values of ambulatory blood pressure-related parameters for moderate renal impairment in resistant hypertension (RH). METHODS: The clinical data were retrospectively analyzed for 401 hospitalized patients with hypertension at our hospital from October 2010 to October 2013. They were divided into RH (n = 263) and non-RH (n = 138). The modified estimating equation of glomerular filtration rate (GFR) for Chinese patients was used to assess renal functions. The standardization of moderate renal impairment was when GFR below 60 ml · min⁻¹ · 1.73 m⁻². The ambulatory blood pressure-related parameters were obtained by 24 h ambulatory blood pressure monitoring. The important prediction of these parameters for moderate renal impairment was accessed by receiver operating characteristic (ROC) curve. And the related risk factors for renal function impairment were tested by multiple stepwise Logistic regression analysis. RESULTS: Ambulatory arterial stiffness index (AASI), 24 h mean pulse pressure (24 hPP), sleeptime relative systolic blood pressure (SBP) decline and 24 h systolic blood pressure (24 hSBP) had important predictive values for moderate renal impairment in RH. GFR was significantly lower in those with AASI ≥ 0.485, 24 hPP ≥ 47.5 mmHg, sleeptime relative SBP decline ≤ -1.75% and 24 hSBP ≥ 130.5 mmHg (P < 0.05). Area under curve of ROC curve of AASI, 24 hPP, sleeptime relative SBP decline and 24 hSBP were 0.804, 0.644, 0.602 and 0.623 respectively. Multiple Logistic regression analysis showed that AASI (OR 1 268.5, P = 0.000), low density lipoprotein (OR 0.7, P = 0.01) and sleeptime relative SBP decline (OR 1.3, P = 0.01) were independent risk factors for GFR < 60 ml · min⁻¹ · 1.73 m⁻² in RH. CONCLUSION: AASI, 24 hPP, sleeptime relative SBP decline and 24 hSBP are the most significant ambulatory blood pressure-related parameters in predicting renal impairment in resistant hypertension.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Hipertensão , Rim , Pressão Sanguínea , Taxa de Filtração Glomerular , Frequência Cardíaca , Humanos , Curva ROC , Insuficiência Renal , Estudos Retrospectivos , Fatores de Risco , Rigidez Vascular
17.
Fish Shellfish Immunol ; 40(1): 146-53, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24972342

RESUMO

The process of programmed cell death process or apoptosis can be regulated by microRNAs, 21-25 nt short non-coding RNAs. However, a comprehensive view of apoptosis-associated miRNAs has not been intensively characterized. In this study, the shrimp miRNA microarray data showed that 199 miRNAs were involved in the regulation of apoptosis, among which 8 miRNAs were evolutionarily conserved in animals. The loss-of-function experiments in vivo in shrimp revealed that miR-100 was served as an anti-apoptosis miRNA through targeting the mRNA of trypsin gene. The results indicated that the silencing of miR-100 expression resulted in the increase of apoptotic activity of shrimp hemocytes and further led to the decreases of virus genome copies in shrimp and virus-infected shrimp mortality compared with the controls. The findings showed that miR-100-trypsin signaling pathway played an important role in the antiviral immunity by regulating apoptosis. Therefore, our study presented a novel miR-100-mediated pathway in the regulation of apoptosis.


Assuntos
Imunidade Inata , MicroRNAs/genética , Penaeidae/fisiologia , Penaeidae/virologia , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Apoptose , Hemócitos/metabolismo , Hemócitos/virologia , MicroRNAs/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Penaeidae/genética , Penaeidae/imunologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais
18.
ScientificWorldJournal ; 2014: 406382, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25295299

RESUMO

Linear controllers have been employed in industrial applications for many years, but sometimes they are noneffective on the system with nonlinear characteristics. This paper discusses the structure, performance, implementation cost, advantages, and disadvantages of different linear and nonlinear schemes applied to the pitch control of the wind energy conversion systems (WECSs). The linear controller has the simplest structure and is easily understood by the engineers and thus is widely accepted by the industry. In contrast, nonlinear schemes are more complicated, but they can provide better performance. Although nonlinear algorithms can be implemented in a powerful digital processor nowadays, they need time to be accepted by the industry and their reliability needs to be verified in the commercial products. More information about the system nonlinear feature is helpful to simplify the controller design. However, nonlinear schemes independent of the system model are more robust to the uncertainties or deviations of the system parameters.


Assuntos
Desenho de Equipamento/métodos , Modelos Lineares , Dinâmica não Linear , Vento , Desenho de Equipamento/normas , Energia Renovável/normas
19.
Sensors (Basel) ; 14(4): 6701-21, 2014 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-24732099

RESUMO

Data aggregation is an important technique for reducing the energy consumption of sensor nodes in wireless sensor networks (WSNs). However, compromised aggregators may forge false values as the aggregated results of their child nodes in order to conduct stealthy attacks or steal other nodes' privacy. This paper proposes a Secure-Enhanced Data Aggregation based on Elliptic Curve Cryptography (SEDA-ECC). The design of SEDA-ECC is based on the principles of privacy homomorphic encryption (PH) and divide-and-conquer. An aggregation tree disjoint method is first adopted to divide the tree into three subtrees of similar sizes, and a PH-based aggregation is performed in each subtree to generate an aggregated subtree result. Then the forged result can be identified by the base station (BS) by comparing the aggregated count value. Finally, the aggregated result can be calculated by the BS according to the remaining results that have not been forged. Extensive analysis and simulations show that SEDA-ECC can achieve the highest security level on the aggregated result with appropriate energy consumption compared with other asymmetric schemes.


Assuntos
Redes de Comunicação de Computadores , Segurança Computacional , Coleta de Dados , Tecnologia sem Fio , Algoritmos , Simulação por Computador , Modelos Teóricos , Fatores de Tempo
20.
Yao Xue Xue Bao ; 49(6): 813-8, 2014 Jun.
Artigo em Zh | MEDLINE | ID: mdl-25212025

RESUMO

N-Acyl-4-phenylthiazole-2-amines were designed and synthesized, moreover their effects on acetylcholinesterase activities were tested. N-Acyl-4-phenylthiazole-2-amines were prepared from substituted 2-bromo-1-acetophenones by three steps reaction, and their AChE inhibitory activities were measured by Ellman method in vitro. The results showed that the target compounds had a certain inhibitory activity on AChE in vitro. Among them, 8c was the best, and IC50 of 8c was 0.51 micromol x L(-1), better than that of rivastigmine and Huperzine-A. The inhibitory activities of N-acyl-4-phenylthiazole-2-amines on acetylcholinesterase are worth while to be further studied.


Assuntos
Aminas/farmacologia , Inibidores da Colinesterase/farmacologia , Desenho de Fármacos , Tiazóis/farmacologia , Acetilcolinesterase/metabolismo , Alcaloides/farmacologia , Aminas/síntese química , Inibidores da Colinesterase/síntese química , Rivastigmina/farmacologia , Sesquiterpenos/farmacologia , Relação Estrutura-Atividade
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