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The wind speed information measured by the wind speed sensor in the wind turbine generator may differ from sufficient wind speed. Therefore, this paper proposes a new effective wind speed calculation method and applies it to the optimal maximum power point tracking (MPPT) of wind energy. After estimating the turbine torque and its rotor speed, the process reverses the turbine’s aerodynamic model. The extended state observer (ESO) based on sliding mode control is used to estimate the aerodynamic torque, which solves complex and challenging tuning of the traditional ESO parameters, and replaces the conventional PI controller, thereby improving the anti-interference and robustness of the system. The sliding mode observer (SMO) is used to estimate the rotor speed. While satisfying the conditions of Lyapunov’s inequality, the design of the SMO is discussed in detail. The wind speed estimation method proposed for evaluating permanent magnet semidirect drive wind turbine and its application performance in maximum power tracking. The simulation was carried out in MATLAB/Simulink; the simulation confirmed that the estimated wind speed under different wind conditions is accurate. Compared with the traditional PI control, the utilization rate of wind energy is increased by 2%, which can be used for the MPPT control of the wind energy conversion system.

Pancreatic ε-cells producing ghrelin are one type of endocrine cell found in islets, which have been shown to influence other intra-islet cells, especially in regulating the function of β cells. However, the role of such cells during β-cell regeneration is currently unknown. Here, using a zebrafish nitroreductase (NTR)-mediated β-cell ablation model, we reveal that ghrelin-positive ε-cells in the pancreas act as contributors to neogenic β-cells after extreme β-cell loss. Further studies show that the overexpression of ghrelin or the expansion of ε-cells potentiates β-cell regeneration. Lineage tracing confirms that a proportion of embryonic ε-cells can transdifferentiate to β-cells, and that the deletion of Pax4 enhances this transdifferentiation of ε-cells to β-cells. Mechanistically, Pax4 binds to the ghrelin regulatory region and represses its transcription. Thus, deletion of Pax4 derepresses ghrelin expression and causes producing more ghrelin-positive cells, enhancing the transdifferentiation of ε-cells to β-cells and consequently potentiating β-cell regeneration. Our findings reveal a previously unreported role for ε-cells during zebrafish β-cell regeneration, indicating that Pax4 regulates ghrelin transcription and mediates the conversion of embryonic ε-cells to β-cells after extreme β-cell loss.

Cysteine (Cys) is one of the most common cellular biothiols and is closely implicated in numerous diseases such as edema, psoriasis, Parkinson's disease, and liver damage. Therefore, detecting Cys activity in complex living organisms is highly necessary for diagnosing related diseases. This study synthesized a near-infrared (NIR) Cys-special probe (MCyA) by introducing an acrylate group to the MCyOH fluorophore. Consequently, Cys could precisely and quickly "light up" strong NIR fluorescence (711 nm) by transforming MCyA into MCyOH. Additionally, MCyA was applied to systematically detect dynamic fluctuations of Cys activity in living cells under different stimulation. The observations indicated that the endogenous Cys activity was depressed when HepG2 cells were under oxidative stress status; however, a dramatic expansion of Cys levels in HepG2 cells with omeprazole stimulation. In particular, MCyA has been successfully used to image the upregulation of Cys level in HepG2 cells in the presence of methionine (Met). Overall, MCyA would be a novel and practical tool to study Cys-related physiological and pathological processes.

Congenital heart disease (CHD) is the most common birth defect worldwide and a main cause of perinatal and infant mortality. Our previous genome-wide association study identified 53 SNPs that associated with CHD in the Han Chinese population. Here, we performed functional screening of 27 orthologous genes in zebrafish using injection of antisense morpholino oligos. From this screen, 5 genes were identified as essential for heart development, including iqgap2, ptprt, ptpn22, tbck and maml3. Presumptive roles of the novel CHD-related genes include heart chamber formation (iqgap2 and ptprt) and atrioventricular canal formation (ptpn22 and tbck). While deficiency of maml3 led to defective cardiac trabeculation and consequent heart failure in zebrafish embryos. Furthermore, we found that maml3 mutants showed decreased cardiomyocyte proliferation which caused a reduction in cardiac trabeculae due to inhibition of Notch signaling. Together, our study identifies 5 novel CHD-related genes that are essential for heart development in zebrafish and first demonstrates that maml3 is required for Notch signaling in vivo.

Electroplating sludge contained multi-metals and organics. In previous reports, electroplating sludges were usually recycled by direct calcination and pyrolysis for structural regulations. For the first time, a metal–organic framework synthesis method was utilized to regulate the structure of an electroplating sludge. In brief, the sludge was hydrothermally treated in solution of 1,3,5-trimesic acid, ethanol, and N,N-dimethylformamide. After this strategy, the sludge particle size was decreased; metals and organics formed coordination bond, and transformed oxygen-centered radicals to carbon-centered radicals; amorphous phases were re-crystalized to form well-dispersed crystals. As a result, the regulated sludge showed an enhanced denitrification activity. It removed 61.6% of nitric oxide (990 ppm) at a temperature as low as 150 °C. The activity was even close to 99.9% at 350 °C. What is more, the regulated sludge was characterized by plenty of free carboxylic groups and multi-metal catalytic centers, which make it a better catalyst than the pure-reagent-synthesized catalyst. Therefore, this paper put forward a novel strategy for the high value-added utilization of electroplating sludge.

A strategy based on in situ growth of a metal–organic framework composite material was proposed by introducing a sodium dodecyl benzenesulfonate (SDBS) group to increase the electrostatic interacti...

Upon extensive hepatocyte loss or impaired hepatocyte proliferation, liver regeneration occurs via biliary epithelial cell (BEC) transdifferentiation, which includes dedifferentiation of BECs into bipotential progenitor cells (BP-PCs) and then redifferentiation of BP-PCs to nascent hepatocytes and BECs. This BEC-driven liver regeneration involves reactivation of hepatoblast markers, but the underpinning mechanisms and their effects on liver regeneration remain largely unknown. Using a zebrafish extensive hepatocyte ablation model, we perform an N-ethyl-N-nitrosourea (ENU) forward genetic screen and identify a liver regeneration mutant, liver logan (lvl), in which the telomere maintenance 2 (tel2) gene is mutated. During liver regeneration, the tel2 mutation specifically inhibits transcriptional activation of a hepatoblast marker, hematopoietically expressed homeobox (hhex), in BEC-derived cells, which blocks BP-PC redifferentiation. Mechanistic studies show that Tel2 associates with the hhex promoter region and promotes hhex transcription. Our results reveal roles of Tel2 in the BP-PC redifferentiation process of liver regeneration by activating hhex.

Poor understanding of the fluid–structure interaction of a wind turbine blade is a well-known bottleneck in the development of the wind power industry. The degree to which different blade vibration...

One of the most important endogenous reactive oxygen species, hypochlorous acid (HClO), is involved in numerous pathological and physiological processes. Herein, a near-infrared fluorescence probe (CyHR) was designed and synthesized for ultrafast (within 0.2 s), sensitive (limit of detection=39.44 nm), and selective response to HClO. The reaction mechanism was systematically analyzed by MS, 1 H NMR spectroscopy, HPLC-MS techniques, and theoretical calculations. The results indicated that HClO can be recognized by CyHR, which is based on chlorine-oxygen (Cl-O) bond formation. To the best of our knowledge, this study is the first to find Cl-O bonds among organic aromatic compounds, given that Cl-O bonds are common among inorganics. Through biological experiments, CyHR was successfully applied to image exogenous and endogenous HClO in macrophage cells (RAW 264.7). Thus, CyHR is a promising tool for HClO-related physiological and pathological studies and may provide a means for designing HClO-specific fluorescence probes.

This paper explores the effects of wearable medical devices (WMDs) in vital sign monitoring, which is the key to telemedicine rehabilitation. First, 60 young patients were selected from the department of oral and maxillofacial surgery in a Chinese hospital. The vital signs of the patients, namely, ear temperature, pulse, blood oxygen saturation, and blood pressure, were measured by both the WMDs and the traditional devices. The measurements were carried out at 6:00, 10:00, 14:00, and 18:00 on the first day of each month in 2018. The comparison between the measured results shows that the WMDs and the traditional devices have no difference in the measured data and measurement time of any vital sign (P > 0.05), but the WMDs consumed much less time in data transcription and the entire measurement process. This means the WMDs are suitable for vital sign measurement in telemedicine rehabilitation.

Aiming to solve the power output reduction caused by the flow separation, this study applied a passive flow control method on blade suction surfaces of a small horizontal axis wind turbine. An airfoil with a semi-elliptical concavity was introduced, and several concave blades were, thus, designed. Among them, the blade with a concavity located at 80% chord and a length of 350 mm was selected for further analysis according to the aerodynamic performance. As a result, it has been found that the concave airfoil had better performance at high wind speeds, low rotational speeds, and small yaw angles, especially the positive yaw conditions. The flow field mechanism could be interpreted with a positive pressure gradient generated by the airfoil concavity. Under the positive yaw angle of 10°, the concavity effect resulted in a greater aerodynamic lift. The azimuth angle of 0° shows an obvious control effect at the blade tip. On the contrary, the concavity has little effect at an azimuth angle of 120° near the leading-edge. At the azimuth angle of 240°, a significant concavity effect at the blade root could be found, while the aerodynamic benefits were not as remarkable as an azimuth angle of 0° in the vicinity of the blade tip. Aside from that, when the flow separation was serious due to the three-dimensional rotational effect, the concavity has no distinct effect on separation control. In essence, the airfoil concavity had a favorable impact on flow separation control and effectively enhanced the power output of the wind turbine.

Determination of mechanical asphyxia as the cause of death has always been difficult for forensic pathologists, particularly when signs of asphyxia are not obvious on the body. Currently, depending on only physical examination of corpses, pathologists must be cautious when making cause-of-death appraisals. In a previous study, four biomarkers-dual-specificity phosphatase 1 (DUSP1), potassium voltage-gated channel subfamily J member 2 (KCNJ2), miR-122, and miR-3185-were screened in human cardiac tissue from cadavers that died from mechanical asphyxia compared with those that died from craniocerebral injury, hemorrhagic shock, or other causes. Expression of the markers correlated with death from mechanical asphyxia regardless of age, environmental temperature, and postmortem interval. However, a single biological index is not an accurate basis for the identification of the cause of death. In this study, receiver operating characteristic curves of the ΔCq values of the four indexes were generated. The diagnostic accuracy of the indexes was judged according to their area under the curve (DUSP1: 0.773, KCNJ2: 0.775, miR-122: 0.667, and miR-3185: 0.801). Finally, a nomogram was generated, and single blind experiment was conducted to verify the cause of death of mechanical asphyxia.

Vitrification is an effective solidification method for heavy metal-containing wastes. However, most investigations focused on the formation of glass matrix. Seldom report discussed the influence of co-existing crystals on heavy metal stabilizations. In this work, Ca-Al-Si phase was formed in the glass matrix by adjusting the composition of feeding ingredient and melting temperature. As a result, when molar ratio of CaO/(SiO2+Al2O3) was lower than 0.97 and reaction temperature was bigger than 1300 °C, small-size Ca-Al-Si phase (Ca2Al2SiO7 and CaAl2Si2O8) was homogeneously distributed in vitreous matrix. At the same time, Cr, Zn, and Pb leaching concentrations were the lowest, far lower than the leaching standard values. According to theoretical calculations, Zn and Pb replaced Ca atom; Cr replaced Al atom in Ca-Al-Si phase under thermal conditions. These replacements resulted in the fixation and stabilization of heavy metals. When the CaO/(SiO2+Al2O3) molar ratio was bigger than 1.00, neither glass nor Ca-Al-Si was formed. Similarly, when the melting temperature was decreased, Ca-Al-Si phase formed a bigger size. Both these went against the stabilization, resulting in high leaching concentrations of heavy metals. The main of this work will help the development of high-temperature melting for the treatment of hazardous wastes.

Leucyl-tRNA synthetase (LARS) is a kind of aminoacyl-tRNA synthetases (aaRSs), which is important for protein synthesis. Following the discovery of three clinical cases which carry LARS mutations, it has been designated as the infantile liver failure syndrome type 1 (ILFS1) gene. ILFS1 is a kind of infantile hepatopathy, which is difficult to diagnose and manage. As the mechanism underlying this disease is poorly understood and LARS is conserved among vertebrates, we obtained zebrafish larsbcq68 mutant via CRISPR/Cas9 technology to investigate the role of larsb in vivo. In mutant, the proliferation ability of liver was drastically decreased at later stages accompanied with severe DNA damage. Further studies demonstrated that the mTORC1 signaling was hyperactivated in larsbcq68 mutant. Inhibition of mTORC1 signaling pathway by Rapamycin or mTORC1 morpholino can partially rescue the liver failure of the mutants. These data revealed that larsb mutation caused ILFS1-like phenotype in zebrafish, and indicated this mutant may serve as a potential model for ILFS1. Furthermore, we demonstrated that rapamycin treatment can partially rescue the liver defect in mutants, thus providing a practicable therapeutic plan for ILFS1.

Acetylcholinesterase (AChE) plays crucial roles in numerous physiological processes such as cell differentiation, cell apoptosis, and nerve tissue developments. Hence, it is highly necessary to design a fluorescent probe for monitoring AChE activity in complex living organisms. In this work, a near-infrared (NIR) off-on probe (CyN) was developed for AChE detection. CyN was exactly synthesized by introducing an N,N-dimethyl carbamyl moiety to hemicyanine (CyOH). AChE can "light up" strong NIR fluorescence through a cleavage special ester bond and transform CyN into CyOH. Moreover, CyN was qualified for imaging the dynamic change of AChE activity in PC12 cells with retinoic acid or hypoxia stimulation. In particular, the probe has been successfully applied for in situ tracing the intact distribution of AChE in living zebrafish. The observations indicate that major occurrence sites of endogenic AChE on zebrafish are the yolk sac and neuromasts. Overall, CyN shows great potential for use in AChE-related physiological studies.

The incidence of death by asphyxia is second to the incidence of death by mechanical injury; however, death by mechanical asphyxia may be difficult to prove in court, particularly in cases in which corpses do not exhibit obvious signs of asphyxia. To identify a credible biomarker of asphyxia, we first examined the expression levels of 47,000 mRNAs in human cardiac tissue specimens from individuals who died of mechanical asphyxia and compared the expression levels with the levels of the corresponding mRNAs in specimens from individuals who died of craniocerebral injury using microarray. We selected 119 differentially expressed mRNAs, examined the expression levels of these mRNAs in 44 human cardiac tissue specimens of individuals who died of mechanical asphyxia, craniocerebral injury, hemorrhagic shock, or other causes. That the expression of dual-specificity phosphatase 1 (DUSP1) and potassium voltage-gated channel subfamily J member 2 (KCNJ2) was upregulated in human cardiac tissues from the mechanical asphyxia group compared with control tissues, regardless of age, environmental temperature, and postmortem interval (PMI), indicating that DUSP1 and KCNJ2 may be associated with mechanical asphyxia-induced death and can thus serve as useful biomarkers of death by mechanical asphyxia.

Wind tunnel experiments of the wake characteristics of a two-blade wind turbine, in the downstream region of 0 / R 10, have been carried out. With the help of the time resolved particle image velocimetry (TRPIV), flow properties such as the vortex structure, average velocity, fluctuations velocities and Reynolds stresses are obtained at different tip speed ratios (TSR). It is found that the wind turbine wake flow can be divided into velocity deficit region, velocity remained region and velocity increased region, with generally higher velocity deficit compared with a three-blade wind turbine wake. Once a blade rotates to the reference 0° plane, the tip vortices generate, shed and move downstream with the intensity gradually decreased. The leapfrogging phenomenon of tip vortices caused by the force interaction of adjacent vortices is found and more apparent in the far wake region. The axial fluctuation velocity is larger than radial fluctuation velocity at the blade root region, and the turbulent kinetic energy shares the similar trend as the axial fluctuation velocity. The axial normalized Reynolds normal stress is much larger than the radial normalized Reynolds normal stress and Reynolds shear stress at the blade root region. As the TSR increases, the radial location where the peak axial normalized Reynolds normal stress u ′ u ′ ¯ / U 2 and axial fluctuation velocity appear descends in the radial direction.

In our previous study, a R code-based mathematical model using RNA degradation patterns was developed for PMI determination in rat brain specimens. However, the postmortem changes of RNA are much more complicated in real cases, and there is still a huge challenge in efficiently applying information in animal data to real cases. In the present study, different RNA markers in both rat and human tissues were collected to screen valid biomarkers and the corresponding mathematical models were established and validated. With the same methodology, multi-RNA markers of myocardium and liver tissues were detected by qPCR and the Ct values of ten biomarkers generally increased with prolonged PMIs. 5S, miR-1 and miR-133a were shown to be optimum reference biomarkers that were not affected by a PMI of up to 5 or more days; however, liver-specific miR-122 began to degrade under higher temperatures and only 5S was selected as an endogenous control in the liver. Among the tested target RNAs, similar to our previous study in brain tissue, β-actin (ΔCt) was found to exhibit the best correlation coefficient with PMI and was employed to build mathematical models using R software. Following validation, the relatively low estimated error demonstrated that PMIs can be accurately predicted in human cases through comprehensive consideration of various factors and using effective biomarkers.

Precisely determining the postmortem interval (PMI) is crucial to civil, criminal and forensic cases. A technique to exploit the postmortem RNA transcript level was developed to increase the accuracy and practicality of PMI estimation. For this purpose, lung tissues and muscle tissues were removed at twelve time points (0–144 h) from rat corpses that had been stored at three different temperatures (10, 20 and 30 °C). Human tissues were collected at autopsy from twelve real cases with known PMI values and other parameters. After the RNA was extracted from all these samples, the transcript levels of nine biomarkers were analyzed by real-time quantitative PCR (RT-qPCR). With the assistance of geNorm, miR-195 , miR-200c , 5S , U6 and RPS29 were selected as reference biomarkers for lung specimens; miR-1 , miR-206 , 5S and RPS29 were chosen as control markers for muscle tissues. On the contrary, ACTB and GAPDH were significantly correlated with the PMI. The mathematical models using these target biomarkers were constructed to describe the characteristic relationship between △Ct values (normalized to reference biomarkers) and the observed PMI for each temperature group. Following validation, the relatively low error rates (7.4% and 12.5% for rat and human samples, respectively) demonstrated the accuracy and reliability of the mathematical model. We believe these results indicate that the multi-parametric mathematical model can become a practical tool for PMI estimation.

The certification of death due to mechanical asphyxia has been a complex problem in some cases. The use of protein expression to identify mechanical asphyxia death has recently attracted attention. Asphyxia creates an extremely hypoxic environment for cells, which should reactivate the mitochondria in the cells. Cyto c and AIF, located in the mitochondria, are transferred to the cytoplasm under hypoxia to trigger the apoptotic process. Based this phenomenon, we designed the animal asphyxia model and cell hypoxia model to examine whether Cyto c and AIF are expressed in the cytoplasm, and we used human samples to verify the results. We found that the two proteins were detectably expressed in the cytoplasm of mechanical asphyxia groups and were hardly detected in the cytoplasm of other groups. This is a promising finding that may shed light on the precise mechanisms associated with mechanical asphyxia.

Genes differentially expressed after death were selected to construct a mathematical model for early postmortem interval estimation. Sprague Dawley rats were sacrificed and placed at temperatures of 4 °C, 15 °C, 25 °C, and 35 °C. Brain tissues were collected at 0, 6, 12, 18, and 24 h after death and total RNA was extracted. Changes in gene transcript levels after death were detected using microarray expression profiling and differentially expressed genes was screened. Expanded experiments were performed to validate gene transcript levels at different temperatures using the reverse transcription real-time quantitative polymerase chain reaction. Six genes with high coefficients of determination were chosen for construction of mathematical models. Optimal ternary cubic equations were built using R software with temperature, postmortem interval and ΔCq defined as the independent variable x, y and z, respectively. Equations were converted into a three-dimensional visual statistical model using MATLAB. Animal samples were used to validate the mathematical models. Results showed that the 5srRNA showed best stability at four temperatures. The genes Ninj2, Grifin, Arpp19, and Hopx showed high coefficients of determination (80%) and low error (3h) in verification experiments which indicate that they are potential markers for early postmortem interval estimation.

Although the optimization of wind turbine blade aerodynamic performance has achieved fruitful results, whether airfoil concavity, an important method for preventing flow separation, is also feasible for improving the aerodynamic performance has not been confirmed scientifically. Thus, we selected the blade of a small horizontal-axis wind turbine as a research model and proposed an optimization method based on airfoil concavity near the trailing edge of the blade suction surface. The experimental results showed that airfoil concavity improved blade aerodynamic performance by 3–15%. Subsequently, its effects on the sound pressure level within the wake flow field were investigated using an acoustic array, and the results suggested that the sound pressure level was reduced by 9.6–15.8%. Lastly, a modal test of the rotor blade was conducted. Although the natural frequencies of the 1st and 2nd order vibrations had hardly changed, their vibrational stiffness were increased by 7 and 4.9%, respectively, which indicated that airfoil concavity significantly improved structural robustness.

Interface regulation is a hot topic in fabricating effective photocatalyst by different semiconductors. Bismuth oxychloride (BiOCl) and layered double hydroxide (LDH) are typical layered materials. For the first time, the effective configuration was revealed between BiOCl and LDH to increase visible-light photocatalytic activity. When LDH grew on BiOCl (0 0 1) facet, photocatalytic activity was low under visible-light irritation. In comparison, when LDH grew on BiOCl (0 1 0) facet, the activity was significantly increased, even though only 1% of LDH was loaded. The increased activity was attributed to the prolonged lifetime of electron-hole pair. As a result, photo-generated carriers resulted in reactive species, such as singlet oxygen, which was trapped by scavenger. However, when over amount of LDH formed and covered BiOCl (0 1 0) facet, the activity of the obtained hybrid decreased. According to these observations and results, a facet-dependent topo-heterostructure was formed by LDH growing on BiOCl (0 1 0) facet.

In the current work, a near-infrared (NIR) fluorescent probe (CyClCP) was developed for fast (35 min), highly sensitive (LOD of 3.75 U/L) and selective response to BChE in vitro and in vivo. Upon the addition of BChE, CyClCP could be efficiently activated with remarkable NIR (λem = 708 nm) fluorescence enhancement and obvious absorbance red shift (581 nm–687 nm). Specifically, according to the subtle differences structural features and substrate preference between BChE and its sister enzyme AChE, CyClCP was constructed by introducing chlorine atom at the ortho-position of the phenolic hydroxyl in the previous reported probe (CyCP). Fortunately, CyClCP exhibited better selectivity towards BChE over AChE compared with CyCP. This molecular design strategy was further rationalized by docking molecular of fluorescence probes (CyClCP and CyCP) and enzymes (BChE and AChE). Finally, CyClCP was membrane permeable and successfully applied to image endogenous BChE level in HepG2 and LO2 cells. Therefore, CyClCP could serve as a promising tool for BChE-related physiological function studies in complex biological systems.

Hypoxia influences different cellular biological processes. To reveal the dynamics of hypoxia's effects on miRNA regulation in vivo, we examined the expression levels of all miRNAs in human brain and heart specimens from cases of mechanical asphyxia compared with those from cases of craniocerebral injury and hemorrhagic shock. We further validated differently expressed miRNAs in another 84 human specimens and rat models. We found that mir-122 was significantly down-regulated and that its putative targets G6PC3, ALDOA and CS were increased in the brain and cardiac tissues in cases of mechanical asphyxia compared with craniocerebral injury and hemorrhagic shock. Our data indicate that mir-122 and its targets G6PC3, ALDOA and CS play roles in the hypoxia responses that regulate glucose and energy metabolism and can serve as hypoxia biomarkers.

Death by mechanical asphyxia is one of the most difficult conclusions to make in forensic science, especially in corpses displaying slight or no trauma to the surface of the body. Therefore, death by mechanical asphyxia is difficult to prove in medico-legal practice. MicroRNAs (miRNAs) are a class of small, non-coding RNAs involved in the regulation of numerous physiological and pathological cellular processes. In the present study, we demonstrate that significantly increased expression of miR-3185 in cardiac tissues was detected among cases of mechanical asphyxia compared to case of craniocerebral injury, hemorrhagic shock, sudden cardiac death and poisoning. We observed no correlation between the expression of miR-3185 and postmortem interval, age or temperature. Further work indicated that CYP4A11 is a putative target gene of miR-3185 and expressed at a relatively low level in cardiac tissue specimens from cases of mechanical asphyxia compared with specimens from cases of craniocerebral injury, hemorrhagic shock, sudden cardiac death and poisoning. Our results suggest that the miRNA-3185/CYP4A11 axis is associated with mechanical asphyxia-induced death and may provide new insight into asphyxial death investigations.

Purpose The postmortem interval (PMI) is the amount of time that has elapsed since the time of death. Over the years, many approaches have been developed to assess PMI, but their time frame of applicability has been only days to weeks. Our present pilot study aimed to find the sensitive mRNA marker if the degradation of mRNA could be used to estimate the early postmortem interval (up to 24 h). Methods In our study, we use the microarray to screen 217 mRNAs markers of rat cardiac tissue. Then, real-time fluorescent quantitative PCR (qPCR) was used to validate of the candidate markers at 7 time points within 24 h and at temperatures of 25 °C and 35 °C. Another 27 rats were then used to verify the model. Results Among all of the candidate markers, △Cq (cell division cycle 25 homolog B(Cdc25b)) had the best correlation coefficient with early postmortem interval and was used to build a new model using the R software. The results of verification testing demonstrated that the error rate was less than 15%, demonstrating the high predictive power of our mathematical model. Conclusion In this study, Cdc25b was found to be the sensitive marker to estimate early postmortem interval, and Rpl27 was found to be suitable for use as the endogenous control. Our work provided new leads for molecular approaches to early postmortem interval estimation using the significant mRNA markers established here.

The purpose of this paper was to effectively apply data mining technology to sci-entifically analyze the students' physical education (PE) performance so as to serve the physical teaching. The methodology adopted in this paper was to apply ASP.NET 3-layer architecture and design and implement college PE performance management and analysis system under the premise of fully analyzing the system requirements based on Visual Studio2008 software development platform and using SQL Server 2005 database platform. Based on data mining technology, students' PE performances were analyzed, and decision tree algorithm was used to make valuable judgments on student performance. The results indicated that applying computer technology to the management and analysis of college PE per-formance can effectively reduce the teaching and managing workload of PE teachers so that the teachers concentrate more on the quality of physical educa-tion.