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91.
Kazeem D. Adeyemi Abdulraheem Abdulrahman Sulyman O. Ibrahim Marili F. Zubair Olubunmi Atolani Abdulhammed A. Badmos 《European Journal of Lipid Science and Technology》2020,122(6)
The influence of dietary Tetracarpidium conophorum (African Walnut) seed meal (TCSM) on fatty acids, productivity parameters, and physicochemical properties of breast and thigh muscles in broiler chickens are assessed. A total of 180, 28‐d‐old Arbor acre broiler chickens are randomly assigned to dietary treatments containing 0% (control), 2.5%, and 5% w/w TCSM, fed for 28 d, and euthanized. Dietary TCSM reduces (p < 0.05) feed intake, body weight gain (BWG), carcass weight, and abdominal fat. Diet does not affect feed efficiency and hematological parameters. The control birds have higher (p < 0.05) serum total cholesterol and triglycerides than do the supplemented birds. Diet has no effect on pH, water holding capacity, carbonyl and malondialdehyde contents, and organoleptic properties of breast and thigh muscles. The 5% TCSM has higher redness in breast muscle than do other treatments. Dietary TCSM improves (p < 0.05) the concentration of C18:3n‐3 (4.80–8.76% vs 1.56%), C20:5n‐3 (0.54–0.79% vs 0.39%), C22:5n‐3 (0.64–0.89% vs 0.18%), and C22:6n‐3 (0.75–0.97% vs 0.19%), and reduces (p < 0.05) the fat content (2.15–2.45% vs 3.15%) in breast and thigh muscles. Dietary TCSM enhances muscle n‐3 fatty acids without instigating oxidative deterioration, but reduces BWG in broiler chickens. Practical Application: Albeit that broiler meat is rich in polyunsaturated fatty acids (PUFA), its omega 6 (n‐6)/omega 3 (n‐3) is >4. Elevated n‐6/n‐3 could have adverse effect on human physiology thereby promoting the pathogenesis of certain diseases. This heightens the need to enhance the n‐3 PUFA content of broiler meat. Dietary TCSM induced up to a fourfold increase in n‐3 PUFA content of the breast and thigh muscles in broiler chickens. Moreover, dietary TCSM induced up to a tenfold decrease in the n‐6/n‐3 of the breast and thigh muscles in broiler chickens. This finding assumes great significance because the health concerns regarding dietary fat are the foremost factors responsible for the bad image suffered by meat. These results provide insights on the potential of TCSM to improve the nutritional quality without compromising the oxidative shelf life, organoleptic traits, and physicochemical properties of broiler meat. 相似文献
92.
93.
Hypoxia formation and breakdown were tracked during 2015 in Muskegon Lake estuary at multiple locations, and five years (2011–2015) of time-series buoy observatory data were evaluated for the effect of episodic wind-events on lake mixing. Bi-weekly water temperature and dissolved oxygen (DO) profiles at four locations revealed that hypoxia occurred at all sites and persisted for 2–3 months during summer 2015. On one date in late-summer, up to 24% of the lake’s volume was estimated to be mildly hypoxic (DO < 4 mg L?1) as defined by lake sturgeon requirements. Patterns of wind speed and water column stability in late spring indicated that high winds and low stability delayed the onset of hypoxia while in late summer low winds and high stability delayed degradation of hypoxia. Wind speeds appear to play a great role in the interannual variability of stratification and subsequent hypoxia. Water temperature and DO profiles taken before and after one mid-summer mixing event (wind speed >7.7 m s?1 for 10 h), indicated that while the wind was unable to completely mix the entire water column, it deepened the epilimnion by ~1.5 m and sheared a thin layer from the upper hypolimnion. By entraining internally loaded nutrients, such episodic wind-events may initiate and sustain algal blooms in nutrient limited surface waters. Quantifying the variable role of wind and mixing events will be key to integrating limnological processes into climate models of the future. 相似文献
94.
Harrison D. Root Gregory Thiabaud Jonathan L. Sessler 《Frontiers of Chemical Science and Engineering》2020,14(1):19
We report here a water-soluble metal cation sensor system based on the as-prepared or reduced form of an expanded porphyrin, texaphyrin. Upon metal complexation, a change in the redox state of the ligand occurs that is accompanied by a color change from red to green. Although long employed for synthesis in organic media, we have now found that this complexation-driven redox behavior may be used to achieve the naked eye detectable colorimetric sensing of several number of less-common metal ions in aqueous media. Exposure to In(III), Hg(II), Cd(II), Mn(II), Bi(III), Co(II), and Pb(II) cations leads to a colorimetric response within 10 min. This process is selective for Hg(II) under conditions of competitive analysis. Furthermore, among the subset of response-producing cations, In(III) proved unique in giving rise to a ratiometric change in the ligand-based fluorescence features, including an overall increase in intensity. The cation selectivity observed in aqueous media stands in contrast to what is seen in organic solvents, where a wide range of texaphyrin metal complexes may be prepared. The formation of metal cation complexes under the present aqueous conditions was confirmed by reversed phase high-performance liquid chromatography, ultra-violet-visible absorption and fluorescence spectroscopies, and high-resolution mass spectrometry. 相似文献
95.
Mauro D. Santos Ivonne Delgadillo Jorge A. Saraiva 《International Journal of Food Science & Technology》2020,55(3):1171-1179
Hyperbaric storage (HS) was evaluated as a new food preservation methodology at room temperature (RT) for beef and pork meat, both minced and in pieces, and compared to refrigeration (RF) storage. The meat samples were stored at 50, 75 and 100 MPa and variable RT up to 60 days. HS at 75 and 100 MPa could not only inhibit microbial growth but also inactivate microorganisms. Regarding physicochemical analyses, an overall equal to better pH maintenance in HS samples was achieved, and similar colour differences between HS and RF were observed. Generally, similarities in moisture content and drip loss between HS (mostly 75 and 100 MPa) and RF were detected (tendency for lower values in the former and higher values in the latter for the higher pressure level). Protein solubility revealed a decrease of sarcoplasmic protein values during storage with a pressure level dependency in some samples. 相似文献
96.
D. M. Mukhammadiev F. Kh. Ibragimov T. D. Mukhammadiev 《Journal of Machinery Manufacture and Reliability》2020,49(3):256-262
The dynamic characteristics of a saw gin as a subsystem with lumped and distributed parameters are considered in the paper. On the basis of investigation of the machine assembly, graphs are drawn that allow establishing the maximum values of the angle of relative rotation and the angle of rotation of the saw cylinder shaft under torsion. 相似文献
97.
C. G. Prosgolitis S. G. Lambrakos A. D. Zervaki 《Journal of Materials Engineering and Performance》2018,27(10):5102-5113
This work presents simulation of microstructure evolution in the nugget zone (NZ) of a AZ31-Mg-alloy friction stir weld. The process parameters (tool geometrical characteristics, rotational speed, travel speed, applied load) have been correlated with the resulting microstructural features in the NZ of the weld (grain size and population) with the aid of the MICRESS software, which provides the ability to simulate both nucleation and grain growth during dynamic recrystallization phenomena evolving in the NZ during the weld thermal cycle. The input parameters of the developed model include the tool geometry, the welding conditions as well as the recrystallization energy, the grain boundary mobility and specific material properties. NZ microstructure obtained by simulation shows good agreement with experimental measurements for both grain population and size. 相似文献
98.
Buryakov A. M. Khusyainov D. I. Mishina E. D. Khabibullin R. A. Yachmenev A. E. Ponomarev D. S. 《Technical Physics Letters》2018,44(12):1115-1119
Technical Physics Letters - The influence of excitation photons energy on the relaxation times of photoexcited carriers is studied. The involved relaxation mechanisms are evaluated and the... 相似文献
99.
Fominski V. Yu. Nevolin V. N. Fominski D. V. Romanov R. I. Gritskevich M. D. 《Technical Physics Letters》2020,46(1):83-86
Technical Physics Letters - We present the results of a comparative investigation of the friction and wear characteristics of MoSx and MoSex coatings in an oxidizing medium (argon–air... 相似文献
100.
Kovchavtsev A. P. Aksenov M. S. Nastov’yak A. E. Valisheva N. A. Gorshkov D. V. Sidorov G. Yu. Dmitriev D. V. 《Technical Physics Letters》2020,46(5):469-472
Technical Physics Letters - The C–V characteristics of Au/Al2O3/In0.52Al0.48As and Au/SiO2/In0.52Al0.48As metal–insulator–semiconductor structures have been studied. It has been... 相似文献