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Chi  Yaxiong  Liu  Jing 《Natural computing》2019,18(2):301-312

Reconstructing gene regulatory networks (GRNs) plays an important role in identifying the complicated regulatory relationships, uncovering regulatory patterns in cells, and gaining a systematic view for biological processes. In order to reconstruct large-scale GRNs accurately, in this paper, we first use fuzzy cognitive maps (FCMs), which are a kind of cognition fuzzy influence graphs based on fuzzy logic and neural networks, to model GRNs. Then, a novel hybrid method is proposed to reconstruct GRNs from time series expression profiles using memetic algorithm (MA) combined with neural network (NN), which is labeled as MANNFCM-GRN. In MANNFCM-GRN, the MA is used to determine regulatory connections in GRNs and the NN is used to determine the interaction strength of the regulatory connections. In the experiments, the performance of MANNFCM-GRN is validated on both synthetic data and the benchmark dataset DREAM3 and DREAM4. The experimental results demonstrate the efficacy of MANNFCM-GRN and show that MANNFCM-GRN can reconstruct GRNs with high accuracy without expert knowledge. The comparison with existing algorithms also shows that MANNFCM-GRN outperforms ant colony optimization, non-linear Hebbian learning, and real-coded genetic algorithms.

  相似文献   
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邓千封  张亮  方立德  王池  刘洋 《计量学报》2020,41(5):567-572
为了解决我国烟道流量计的量值溯源问题,中国计量科学研究院建立了烟道流量计量标准装置。装置使用可溯源至标准转盘的激光多普勒测速仪作为原级标准器,采用激光多普勒流速剖面扫描和超声流量计波动修正的方式测量标准流量,经校准的8声道超声流量计为工作级标准表,具备了908~104840m3/h的测量能力,扩展不确定度为0.62%(k=2),可对最大口径为1m的流量计进行校准。装置下游测试段包括圆形管段和矩形管段,能够开展烟道流量计测量性能的研究。  相似文献   
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Rapid and sensitive point-of-care testing (POCT) is an extremely critical mission in practical applications, especially for rigorous military medicine, home health care, and in the third world. Here, we report a visual POCT method for adenosine triphosphate (ATP) detection based on Taylor rising in the corner of quadratic geometries between two rod surfaces. We discuss the principle of Taylor rising, demonstrating that it is significantly influenced by contact angle, surface tension, and density of the sample, which are controlled by ATP-dependent rolling circle amplification (RCA). In the presence of ATP, RCA reaction effectively suppresses Taylor-rising behavior, due to the increased contact angle, density, and decreased surface tension. Without addition of ATP, untriggered RCA reaction is favorable for Taylor rising, resulting in a significant height. With this proposed method, visual sensitive detection of ATP without the aid of other instruments is realized with only a 5 μL droplet, which has good selectivity and a low detection limit (17 nM). Importantly, this visual method provides a promising POCT tool for user-friendly molecular diagnostics.  相似文献   
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The expression of cytokeratins (CK), involucrin, vimentin, CD34, and alpha-smooth-muscle actin was studied in fetal and adult hair follicles. The first stage of the developing hair follicle is characterized by palisaded, elongated epithelial cells budding from the epidermal basal layer. These cells express CK5/6, CK14, CK17, CK19, and vimentin. During the following weeks of gestation, different structures in the developing hair follicle can be identified and characterized. The matrical cells display only CK19. The keratinocytes of the outer root sheath express CK5/6, CK14, CK17, CK19, and involucrin; those of the inner root sheath, CK4, CK18, and involucrin; those of the isthmus, the same profile as the ORS. In the infundibulum, the basal-layer keratinocytes express CK5/6, CK14, CK17, and CK19, whereas in the suprabasal layers CK1, CK4, CK10, CK14, and CK17 are seen. The adult hair follicle in anagen fails to express CK19 in the matrical cells and isthmus and both CK17 and CK19 in the infundibulum. These profiles of intermediate filaments and other markers appear to be potentially useful in categorizing neoplasms with apparent follicular differentiation.  相似文献   
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PURPOSE: To summarize the pathologic diagnoses of a large number of surgically-obtained specimens over an extended time period in a single ophthalmic pathology laboratory. METHODS: We analyzed the records of 24,444 surgically obtained specimens accessioned in the L.F. Montgomery Ophthalmic Pathology Laboratory, Emory University, Atlanta, GA between May 1941 and December 1995. Age, sex, topography, clinical procedure, and histologic diagnosis were entered into a database using the modified SNOMED coding system. The diagnosis of the surgically enucleated eyes were analyzed with respect to years of enucleation. RESULTS: The most common topographic area associated with a histologic diagnosis was the cornea (39.3%), followed by lens (16.0%), vitreous (12.0%), uvea (9.8%), eyelids (8.0%), conjunctiva (7.7%), retina (7.7%), and orbit (2.1%). The relative proportion of vitreous specimens has continuously increased and became the most common surgical specimen in 1995. The most common underlying disease of surgically enucleated eyes is trauma (40.9%), followed by ocular neoplasia (24.2%), 'surgical' diseases of the cornea, lens and retina including glaucoma (17.3%), vascular diseases (6.7%), and inflammatory conditions (6.7%). The relative frequency of trauma and ocular inflammation as a cause of enucleation decreased significantly (p < 0.05) over the time of the study period while the relative proportion of ocular neoplastic processes increased (p < 0.0001). CONCLUSIONS: The availability of new surgical techniques has caused a change in the relative frequencies of different ocular specimens submitted for histologic examination.  相似文献   
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Recent technological advances have made it possible to support long lifetime and large volume streaming data transmissions in sensor networks. A major challenge is to maximize the lifetime of battery-powered sensors to support such transmissions. Battery, as the power provider of the sensors, therefore emerges as the key factor for achieving high performance in such applications. Recent study in battery technology reveals that the behavior of battery discharging is more complex than we used to think. Battery powered sensors might waste a huge amount of energy if we do not carefully schedule and budget their discharging. In this paper we study the effect of battery behavior on routing for streaming data transmissions in wireless sensor networks. We first give an on-line computable energy model to mathematically model battery discharge behavior. We show that the model can capture and describe battery behavior accurately at low computational complexity and thus is suitable for on-line battery capacity computation. Based on this battery model we then present a battery-aware routing (BAR) protocol to schedule the routing in wireless sensor networks. The routing protocol is sensitive to the battery status of routing nodes and avoids energy loss. We use the battery data from actual sensors to evaluate the performance of our protocol. The results show that the battery-aware protocol proposed in this paper performs well and can save a significant amount of energy compared to existing routing protocols for streaming data transmissions. Network lifetime is also prolonged with maximum data throughput. As far as we know, this is the first work considering battery-awareness with an accurate analytical on-line computable battery model in sensor network routing. We believe the battery model can be used to explore other energy efficient schemes for wireless networks as well.  相似文献   
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This study investigates the ozonation of CI Reactive Black 5 (RB5) by using the rotating packed bed (RPB) and completely stirred tank reactor (CSTR) as ozone contactors. The RPB, which provides high gravitational force by adjusting the rotational speed, was employed as a novel ozone contactor. The same ozone dosage was separately introduced into either the RPB or the CSTR for the investigation, while the experimental solution was continuously circulated within the apparatus consisting of the RPB and CSTR. The decolorization and mineralization efficiencies of RB5 in the course of ozonation are compared for these two methods. Moreover, the dissolved and off‐gas ozone concentrations were simultaneously monitored for the further analysis. As a result, the ozone mass transfer rate per unit volume of the RPB was significantly higher because of its higher mass transfer coefficient and gas–liquid concentration driving force. Furthermore, ozonation kinetics was found to be independent of the gravitational magnitude of an ozone gas–liquid contactor. Therefore, the results suggest employing RPBs as ozone‐contacting devices with the advantage of volume reduction. The experimental results, which can be used for further modeling of the ozonation process in the RPB, also show the requirement of correct design for the RPB. Consequently, the present study is useful for the understanding of practical application of RPBs. Copyright © 2004 Society of Chemical Industry  相似文献   
10.
The 20-kDa protein gene is androgen regulated in rat ventral prostate. Intron 1 contains a 130-base pair complex response element (D2) that binds androgen (AR) and glucocorticoid receptor (GR) but transactivates only with AR in transient cotransfection assays in CV1 cells using the reporter vector D2-tkCAT. To better understand the function of this androgen-responsive unit, nuclear protein interactions with D2 were analyzed by DNase I footprinting in ventral prostate nuclei of intact or castrated rats and in vitro with ventral prostate nuclear protein extracts from intact, castrated, and testosterone-treated castrated rats. Multiple androgen-dependent protected regions and hypersensitive sites were identified in the D2 region with both methods. Mobility shift assays with 32P-labeled oligonucleotides spanning D2 revealed specific interactions with ventral prostate nuclear proteins. Four of the D2-protein complexes decreased in intensity within 24 h of castration. UV cross-linking of the androgen-dependent DNA binding proteins identified protein complexes of approximately 140 and 55 kDa. The results demonstrate androgen-dependent nuclear protein-DNA interactions within the complex androgen response element D2.  相似文献   
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