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Objective: Combined with the determination of macromolecular protein, amino acid and total protein, a quantitative analysis method for the content of small molecular peptides in infant formula milk powder was established. Methods: The contents of total protein, polymer protein and free amino acid in infant formula milk powder were determined by Kjeldahl nitrogen determination method, gravimetric method and ion exchange chromatography, and then the contents of small molecular protein peptide were calculated. Results: The precision RSD of the macromolecular protein detection (n=6) was 0.74%; The recovery rates of the 17 kinds of amino acids were 91.0%~103.2%, and the relative deviations of the detection results were 0.6%~ 2.5%. The recovery rates of small molecular weight peptides were 95.2%~98.2%. Conclusion: The established method has been validated by methodology, with good precision and recovery rate, and can be used for the determination of small molecular peptides in infant formula milk powder.

The experiment aimed to explore the effects of compound organic acidifiers on the production performance, egg quality, serum biochemical indexes, and economic benefits of laying hens in the late laying period. Five hundred and forty 72-week-old Jingfen No.2 laying hens with similar body condition were selected and randomly divided into three groups (CON group, L-COA group, and H-COA group), with six replicates in each group and 30 hens in each replicate. Each group was fed the same diet. The CON group drank tap water throughout the whole process. The L-COA group and H-COA group added 0.10% and 0.15% compound organic acidifiers to the drinking water, respectively. The test period was 42 days. The results showed that compared to the CON group, the egg production rate and egg qualified rate of the L-COA group were significantly increased (P<0.05), the egg production rate, average egg weight, and egg qualified rate of the H-COA group were significantly increased (P<0.05). The eggshell strength and egg yolk score of the L-COA group were significantly improved (P<0.05). The serum low-density lipoprotein content and alanine aminotransferase activity in the L-COA group and H-COA group were significantly reduced (P<0.05). The breeding profits of the L-COA group and H-COA group increased by 1.08% and 13.64%, respectively. The study indicates that adding compound organic acidifiers to the drinking water of laying hens during the late laying period has a positive effect on egg production efficiency, egg quality, serum biochemical indexes, and economic benefits, and the better effect is achieved when the added amount of compound organic acidifiers is 0.15%. [ABSTRACT FROM AUTHOR]

The purpose of this experiment was to explore the effects of crude extract of Codonopsis pilosula and Astragalus membranaceus (CAE) on growth performance, serum biochemical index, immune organ index, and intestinal morphology of Sanhuang chickens. A total of 360 one-day-old Guangxi Sanhuang chicks weighing (27.0±0.5) g and in good physiological condition were randomly divided into three groups with six replicates in each group and 20 chickens in each replicate. CON group was fed a basal diet, CAE group was fed basal diet with 2.5 g/kg crude extract of Codonopsis pilosula and Astragalus membranaceus, and ANT group was fed basal diet with 0.05 g/kg chlortetracycline. The trial period was 42 days. The results showed that compared with CON group, the final weight and average daily gain of CAE group and ANT group increased significantly (P<0.05), the feed-to-weight ratio decreased significantly (P<0.05), and the mortality rate decreased by 3.33% (P>0.05). Compared with CON group, the activity of aspartate aminotransferase and the content of triglyceride and cholesterol in serum of CAE group and ANT group decreased significantly (P<0.05). Compared with CON group, CAE group and ANT group had significantly higher French capsule index (P<0.05). Compared with CON group, the villus height and villus-saphenous ratio of twelve intestines in CAE group and ANT group were significantly higher (P<0.05). The study indicates that the crude extract of Codonopsis pilosula and Astragalus membranaceus has positive effects on the growth performance, serum biochemical index, immune organ index and intestinal morphology of Sanhuang chickens, which was equivalent to the application effect of antibiotics. [ABSTRACT FROM AUTHOR]

A rapid identification method of microcrystalline cellulose adulteration by near infrared spectroscopy was studied. Based on the near-infrared spectrum data of microcrystalline cellulose samples and adulterants (soluble starch, wheat flour), the material spectrum database and the adulterant spectrum database were created respectively, and the microcrystalline cellulose classification and the adulterant models were also established. A rapid identification method for microcrystalline cellulose adulteration was established by using the Adulterant Screen algorithm technology for calculation and analysis. The minimum detected content of single component adulteration of microcrystalline fiber powder was 2% soluble starch and 1% wheat flour, and the accurate recognition rate was 100%. When the adulteration of two components (soluble starch + wheat flour) was two to ten times of the detection limit concentration of one component, the accurate recognition rate was 100%. The accurate recognition rate of unknown sample microcrystalline cellulose above the detection limit is 100%. The method is simple, rapid and reliable, and can quickly identify adulteration of microcrystalline cellulose samples. It can be effectively applied to the adulteration detection and identification of daily microcrystalline cellulose samples, which could provide technical support for the customs to crack down on tax evasion and evasion.

Two new Fe 3 ( μ 3 ‐O) complexes, [Fe 3 ( μ 3 ‐O)(O 2 CC 6 H 4 F) 6 (OCH 3 )(2H 2 O)]NO 3 ·2H 2 O (1), and [Fe 3 ( μ 3 ‐O)(O 2 CCH 3 ) 6 (3H 2 O)] 3 ·4H 2 O (2), have been synthesized and characterized by X‐ray crystal structural analysis. Both (1) and (2) belong to monoclinic system. For (1), space group is P 2 1 /n. a=14.662(3) Å, b =22.080(4) Å, c =15.501(3) Å, β =96.91(3)°, U =4982.0(17) Å 3 , Z =4, Dx =1.578 g cm -3 . While for (2), space group is C 2/ c , a =15.317(6) Å, b =26.113(6) Å, c =23.622(6) Å, β =96.475(6)°, U =9388(5) Å 3 , Z =4, Dx =1.713 g cm -3 . [ABSTRACT FROM AUTHOR]

Objective: To establish the finite element model of spinal canal reconstruction and internal fixation,analysis influence of spinal canal reconstruction and internal fixation on spinal stability,and verify the effectiveness and reliability of spinal canal reconstruction and internal fixation in spinal canal surgery., Methods: A 30-year-old male healthy volunteer with a height of 172 cm and weight of 75 kg was selected and his lumbar CT data were collected to establish a finite element model of normal lumbar L 3 -L 5 ,and the results were compared with in vitro solid results and published finite element analysis results to verify the validity of the model. They were divided into normal group,laminectomy group and spinal canal reconstruction group according to different treatment methods. Under the same boundary fixation and physiological load conditions,six kinds of activities were performed,including forward bending,backward extension,left bending,right bending,left rotation and right rotation,and the changes of range of motion (ROM) of L 3 -L 4 ,L 4 -L 5 segments and overall maximum ROM of L 3 -L 5 were analyzed under the six conditions., Results: The ROM displacement range of each segment of the constructed L 3 -L 5 finite element model was consistent with the in vitro solid results and previous literature data,which confirms the validity of the model. In L 3 -L 4 ,ROM of spinal canal reconstruction group was slightly increased than that of normal group during posterior extension(>5% difference),and ROM of other conditions was similar to that of normal group(<5% difference). ROM in laminectomy group was significantly increase than that in normal group and spinal canal reconstruction group under the condition of flexion,extension,left and right rotation. In L 4 -L 5 ,ROM in spinal canal reconstruction group was similar to that in normal group(<5% difference),while ROM in laminectomy group was significantly higher than that in normal group and spinal canal reconstruction group(>5% difference). In the overall maximum ROM of L 3 -L 5 ,spinal canal reconstruction group was only slightly higher than normal group under the condition of posterior extension(>5% difference),while laminectomy was significantly higher than normal group and spinal canal reconstruction group under the condition of anterior flexion,posterior extension,left and right rotation(>5% difference). The changes of each segment ROM and overall ROM of L 3 -L 5 showed laminectomy group>spinal canal reconstruction group>normal group., Conclusion: Laminectomy could seriously affect biomechanical stability of the spine,but application of spinal canal reconstruction and internal fixation could effectively reduce ROM displacement of the responsible segment of spine and maintain its biomechanical stability.