Tianjin Agricultural University

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Li T.,Tianjin University | Zhao H.,Tianjin Agricultural University
ISA Transactions | Year: 2017

The paper addresses the finite-time convergence problem of a uncalibrated camera-robot system with uncertainties. These uncertainties include camera extrinsic and intrinsic parameters, robot dynamics and feature depth parameters, which are all considered as time-varying uncertainties. In order to achieve a better dynamic stability performance of the camera-robot system, a novel FTS adaptive controller is presented to cope with rapid convergence problem. Meanwhile, FTS adaptive laws are proposed to handle these uncertainties which exist both in robot and in camera model. The finite-time stability analysis is discussed in accordance with homogeneous theory and Lyapunov function formalism. The control method we proposed extends the asymptotic stability results of visual servoing control to a finite-time stability. Simulation has been conducted to demonstrate the performance of the trajectory tracking errors convergence under control of the proposed method. © 2017 ISA.

Wang J.,Tianjin Agricultural University
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2017

In order to change traditional PE teaching mode and realize the interconnection, interworking and sharing of PE teaching resources, a distance PE teaching platform based on broadband network is designed and PE teaching information resource database is set up. The designing of PE teaching information resource database takes Windows NT 4/2000Server as operating system platform, Microsoft SQL Server 7.0 as RDBMS, and takes NAS technology for data storage and flow technology for video service. The analysis of system designing and implementation shows that the dynamic PE teaching information resource sharing platform based on Web Service can realize loose coupling collaboration, realize dynamic integration and active integration and has good integration, openness and encapsulation. The distance PE teaching platform based on Web Service and the design scheme of PE teaching information resource database can effectively solve and realize the interconnection, interworking and sharing of PE teaching resources and adapt to the informatization development demands of PE teaching. © 2017 SPIE.

Ma L.,Tianjin Agricultural University | Xiong Y.L.,University of Kentucky
Meat Science | Year: 2011

The objective of the study was to create marbling-like fat in lean pork with acceptable oxidative stability through the injection of canola/olive oil-substituted emulsions. Pork loins were injected with 5% water as control (CW) or 5% emulsion containing no tocopherols (E) or 0.07% tocopherols (ET) and stored at 2 °C in an oxygen-enriched package for up to 3. weeks. Lipid oxidation was totally inhibited in ET pork but increased 3-fold to 0.20. mg malonaldehyde/kg in CW and E pork after 3. weeks. ET treatment also had a positive effect on meat red color. Emulsion-containing pork, showing less protein oxidation (carbonyl and disulfide formation), had reduced drip loss and shear force than CW samples (P< 0.05). The results indicated that incorporation of antioxidant-containing emulsions could create marbling-like texture in lean pork without compromising oxidative stability. © 2011.

Cheng Z.,Tianjin Agricultural University | Gatlin D.M.,Texas A&M University | Buentello A.,Schillinger Genetics
Aquaculture | Year: 2012

Various studies with fish species indicate that dietary arginine (Arg) and glutamine (Gln) supplementation may support an enhanced performance beyond simply improving weight gain. Therefore, a feeding trial was conducted to determine the effects of dietary Arg or Gln on growth performance, immune responses and intestinal morphology of juvenile hybrid striped bass, Morone chrysops×. Morone saxatilis (4.1 ± 0.02. g, initial average weight). The basal diet was formulated from menhaden fishmeal and solvent-extracted soybean meal to contain 45% crude protein and 10% lipid. Arginine and Gln were singularly added to the basal diet at either 1% or 2% or both amino acids were added in combination at 1% to formulate experimental diets with adjustments in glycine to maintain all diets iso-nitrogenous. Fish were fed the experimental diets for a period of 8. weeks, at the end of which final weight, specific growth rate and feed efficiency were significantly (P< 0.05) higher in fish fed diets supplemented with Arg at either 1 or 2%, Gln at 1%, Arg and Gln both at 1%, but not in those fed the diet supplemented with Gln at 2%.Arginine and/or Gln supplementation tended to improve neutrophil oxidative radical production, but not significantly (P> 0.05). However, significantly higher serum lysozyme activity was observed in fish fed the diet supplemented with Arg at either 1 or 2% and Gln at 1%. Intracellular superoxide anion production by hybrid striped bass macrophages also tended to increase, while extracellular superoxide anion production was significantly improved by supplementation of Arg at 1% and Gln at either 1 or 2% of diet.Morphometric analyses demonstrated positive effects of both dietary Arg and Gln on histo-morphological measurements in different portions of the gastrointestinal tract of hybrid striped bass. The 1% Arg diet resulted in the greatest increases in size of the chosen enteric structures, but the other four experimental diets also significantly improved the scores for various intestinal portions compared to fish fed the basal diet.Results from the present experiment demonstrate the importance of dietary supplementation of both Arg and Gln in improving growth performance, eliciting positive changes to several components of the innate immune system, and also benefiting the intestinal functionality of hybrid striped bass. © 2012 Elsevier B.V.

Yang R.,Tianjin University | Yang R.,Tianjin Agricultural University | Liu R.,Tianjin University | Xu K.,Tianjin University
Food Bioscience | Year: 2013

A new approach for qualitative and quantitative analysis of adulterated milk is proposed by combining two-dimensional correlation spectroscopy (2DC0S) with multi-way partial least squares (N-PLS). Forty pure milk and 40 adulterated milk samples with melamine were prepared and the infrared absorption spectra were measured. The two-dimensional (2D) correlation spectra were calculated to construct the multi-way partial least squares discriminant analysis (NPLS-DA) model for milk adulterated with melamine. Our study showed the higher accuracy of predicting adulterated milk of 95% using NPLS-DA, versus 85% using conventional one-dimensional spectra and partial least squares discriminant analysis (PLS-DA). Also, the quantitative analysis models were constructed to determine concentration of melamine in milk. The root mean square error of prediction (RMSEP) was 0.106 gL-1 using the N-PLS method and 0.16 gL-1 using conventional one-dimensional spectra and partial least squares (PLS). Comparison results show that the proposed new method is superior to the traditional method and the use of 2DCOS with N-PLS is promising to quantify the adulterants in pure milk. © 2012 Elsevier Ltd.

Xu J.,Tianjin University | Li Y.,Tianjin Agricultural University
Molecular Medicine Reports | Year: 2012

Intense exercise increases oxygen consumption and may produce an imbalance between reactive oxygen species (ROS) and antioxidants, inducing oxidative stress as a result of increased ROS production. Exogenous antioxidants may prevent oxidative damages since they are able to detoxify certain peroxides by scavenging the ROS produced during exercise. The aim of this study was to evaluate the effects of salidroside on exhaustive exercise-induced oxidative stress in rats. A total of 40 animals were randomly divided into four groups of ten rats each: control (C), low-dose salidroside-treated (LT), middle-dose salidroside-treated (MT) and high-dose salidroside-treated (HT) groups. The rats in the treated groups received salidroside (25, 50 and 100 mg/kg, respectively) intragastrically (ig) and the rats in the control group received drinking water ig for 4 weeks. After 4 weeks, the rats performed an exhaustive swimming exercise and exhaustive swimming times were recorded. The malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glycogen levels in the liver tissues of the rats were measured. The data revealed that salidroside was able to elevate the exercise tolerance and increase the liver glycogen levels of the rats following exhaustive exercise. Salidroside was also able to reduce MDA levels and enhance the activities of antioxidant enzymes (CAT, SOD and GSH-Px) in the liver tissues of the rats. The results from this study indicate that salidroside is effective in the prevention of oxidative stress following exhaustive exercise.

The objectives of this study were to reveal protein molecular structure in relation to rumen degradation kinetics and intestinal availability in combined feeds of hulless barley with bioethanol coproduct [pure wheat dried distillers grains with solubles (DDGS)] at 5 different ratios (100:0, 75:25, 50:50, 25:75, and 0:100) in dairy cattle. The parameters assessed included 1) protein chemical profiles, 2) protein subfractions partitioned by the Cornell Net Carbohydrate and Protein System, 3) in situ protein degradation kinetics, 4) truly absorbed protein supply in the small intestine (DVE), metabolizable protein characteristics and degraded protein balance (OEB), 5) protein molecular structure spectral profiles, and 6) correlation between protein molecular structure and protein nutrient profiles and metabolic characteristics. We found that 1) with increasing inclusion of wheat DDGS in feed combinations, protein chemical compositions of crude protein (CP), neutral detergent-insoluble CP, acid detergent-insoluble CP, and nonprotein N were increased, whereas soluble CP was decreased linearly; CP subfractions A, B3, and C were increased linearly, but CP subfractions B1 and B2 were decreased; truly digestible CP increased but total digestible nutrients at 1× maintenance decreased linearly; protein degradation rate was decreased without affecting potentially soluble, potentially degradable, and potentially undegradable fractions, and both rumen-degradable protein and rumen-undegradable protein were increased; by using the DVE/OEB system, the DVE and OEB values were increased from 98 to 226g/kg of dry matter and -1 to 105g/kg of dry matter, respectively; 2) by using the molecular spectroscopy technique, the spectral differences in protein molecular structure were detected among the feed combinations; in the original combined feeds, amide I and II peak area and ratio of amide I to II were increased linearly; although no difference existed in α-helix and β-sheet height among the combinations, the ratio of α-helix to β-sheet height was changed quadratically; 3) in the in situ 48-h residue samples, amide I and amide II peak area intensities were increased linearly and the ratio of amide I to II peak area was decreased linearly from 4.28 to 2.63; α-helix and β-sheet height of rumen residues were similar among 5 feed combinations; and 4) the ratio of α-helix to β-sheet height in original feed combinations was strongly correlation with protein chemical and nutrient profiles, but the ratio of amide I to II area had no significant correlation with all items that were tested; no correlation was found between the ratio of α-helix to β-sheet height of the in situ rumen residues and protein chemical and nutrient profiles. In conclusion, by integration of hulless barley with bioethanol coproduct of wheat DDGS, feed quality in combined feeds was improved and more optimized. Adding wheat DDGS increased linearly CP, truly digestible CP, rumen-degradable protein, rumen-undegradable protein, DVE, and OEB values in combined feeds. The molecular spectral differences of protein molecular structures (amide I and II area intensities, the ratio of amide I to amide II, and the ratio of α-helix to β-sheet height among feed combinations) were detected among the combinations. This may partially explain the biological differences in protein chemical profiles and protein utilization and availability in dairy cattle. In the original combined feeds, protein α-helix-to-β-sheet ratio had significant correlations with protein chemical and nutrient profiles, but in in situ 48-h residue samples, protein amide I-to-II ratio had significant correlations with protein chemical and nutrient profiles. This study may provide an insight into how to more efficiently use hulless barley grain (high energy and high degradation rate) and wheat DDGS (high metabolizable protein and low degradation rate) in beef and dairy production systems. © 2012 American Dairy Science Association.

Zhang L.,Tianjin Agricultural University | Wang X.,Shandong Academy of Sciences
Journal of Separation Science | Year: 2010

The hydrophobic ionic liquid of [BMIM][PF6] was successfully used for the ultrasound-assisted extraction of hydrophobic magnolol and honokiol from cortex Magnoliae officinalis. To obtain the best extraction efficiencies, some ultrasonic parameters including the concentration of [BMIM][PF 6], pH, ultrasonic power and ultrasonic time were evaluated. The results obtained indicated that the [BMIM][PF6]-based ultrasound-assisted extraction efficiencies of magnolol and honokiol were greater than those of the [BMIM][BF4]-based ultrasound-assisted extraction (from 48.6 to 45.9%) and the traditional ethanol reflux extraction (from 16.2 to 13.3%). Furthermore, the proposed extraction method is validated by the recovery, correlation coefficient (R2) and reproducibility (RSD, n=5), which were 90.8-102.6, 0.9992-0.9998, and 1.6-5.4%, respectively. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA.

Peng J.-X.,Tianjin Agricultural University
Materials Science Forum | Year: 2016

A innovative method to simplify calculation the kinetics model is applied to wood pyrolysis. Thermal degradation of basswood was investigated with thermogravimetry. The thermal kinetic TG analysis of basswood under N2 atmosphere was studied at the heating rate of 10,20, 30, 90K/min. All the TG curves are divided into four parts which are drying, slow pyrolysis, fast pyrolysis, and carbonization. The third one is employed to determine the parameters for around 69% of the total mass loss occurs in this range. The peak of the composition is according with DTG curve. It validate assumption of reaction stage.According to the developed method, the react order, reaction energy and pre-exponential factor are obtained, which are in the range of 2.8~4.3, 101.7~126.6 kJ/mol and 2.3×108~7.0×1010min-1, respectively, which are in the range of that reported previously. As a comparison experimental data with calculated data, the well fitting results indicate that this method is appropriate for simulating wood pyrolysis kinetics. © 2016 Trans Tech Publications, Switzerland.

This study was conducted to compare: (1) protein chemical characteristics, including the amide I and II region, as well as protein secondary structure; and (2) carbohydrate internal structure and functional groups spectral intensities between the frost damaged wheat and normal wheat using synchrotron radiation-based Fourier transform infrared microspectroscopy (SR-FTIRM). Fingerprint regions of specific interest in our study involved protein and carbohydrate functional group band assignments, including protein amide I and II (ca. 1774-1475 cm(-1)), structural carbohydrates (SCHO, ca. 1498-1176 cm(-1)), cellulosic compounds (CELC, ca. 1295-1176 cm(-1)), total carbohydrates (CHO, ca. 1191-906 cm(-1)) and non-structural carbohydrates (NSCHO, ca. 954-809 cm(-1)). The results showed that frost did cause variations in spectral profiles in wheat grains. Compared with healthy wheat grains, frost damaged wheat had significantly lower (p < 0.05) spectral intensities in height and area ratios of amide I to II and almost all the spectral parameters of carbohydrate-related functional groups, including SCHO, CHO and NSCHO. Furthermore, the height ratio of protein amide I to the third peak of CHO and the area ratios of protein amide (amide I + II) to carbohydrate compounds (CHO and SCHO) were also changed (p < 0.05) in damaged wheat grains. It was concluded that the SR-FTIR microspectroscopic technique was able to examine inherent molecular structure features at an ultra-spatial resolution (10 × 10 μm) between different wheat grains samples. The structural characterization of wheat was influenced by climate conditions, such as frost damage, and these structural variations might be a major reason for the decreases in nutritive values, nutrients availability and milling and baking quality in wheat grains.

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