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101.
India stood first for millet production in the world and plays a significant role in meat production and consumption too. To meet the demand of health conscious consumers for healthy and nutritious meat food item, the incorporation of millet grains and its byproducts to the meat products by the processors can serve the purpose. The multidimensional positive nutritional and functional characteristics millet grain not only improve the acceptability of the meat products but also increase its own demand as a main coarse food grain in competition to the wheat and rice over the world. 相似文献
102.
Stability, bioavailability, and bacterial toxicity of ZnO and iron-doped ZnO nanoparticles in aquatic media 总被引:1,自引:0,他引:1
Li M Pokhrel S Jin X Mädler L Damoiseaux R Hoek EM 《Environmental science & technology》2011,45(2):755-761
The stability and bioavailability of nanoparticles is governed by the interfacial properties that nanoparticles acquire when immersed in a particular aquatic media as well as the type of organism or cell under consideration. Herein, high-throughput screening (HTS) was used to elucidate ZnO nanoparticle stability, bioavailability, and antibacterial mechanisms as a function of iron doping level (in the ZnO nanoparticles), aquatic chemistry, and bacterial cell type. ζ-Potential and aggregation state of dispersed ZnO nanoparticles was strongly influenced by iron doping in addition to electrolyte composition and dissolved organic matter; however, bacterial inactivation by ZnO nanoparticles was most significantly influenced by Zn(2+) ions dissolution, cell type, and organic matter. Nanoparticle IC(50) values determined for Bacillus subtilis and Escherichia coli were on the order of 0.3-0.5 and 15-43 mg/L (as Zn(2+)), while the IC(50) for Zn(2+) tolerant Pseudomonas putida was always >500 mg/L. Tannic acid decreased toxicity of ZnO nanoparticles more than humic, fulvic, and alginic acid, because it complexed the most free Zn(2+) ions, thereby reducing their bioavailability. These results underscore the complexities and challenges regulators face in assessing potential environmental impacts of nanotechnology; however, the high-throughput and combinatorial methods employed promise to rapidly expand the knowledge base needed to develop an appropriate risk assessment framework. 相似文献
103.
Chitosan inhibits premature browning in ground beef 总被引:1,自引:0,他引:1
Our objective was to evaluate the effect of chitosan on premature browning in refrigerated ground beef patties stored in different packaging systems. Ground beef patties (15% fat) with chitosan (1% w/w) or without chitosan (control) were individually packaged either in vacuum (VP), aerobic packaging (AP), carbon monoxide modified atmosphere packaging (LO-OX; 0.4% CO+19.6% CO(2)+80% N(2)), or high-oxygen modified atmosphere packaging (HI-OX; 80% O(2)+20% CO(2)), and stored for 0, 1, or 3 days at 1°C. At the conclusion of storage, raw surface redness was evaluated, patties were cooked to internal end-point temperatures of either 66°C or 71°C, and internal cooked color was measured. The incorporation of chitosan increased (P<0.05) the interior redness of patties stored in AP, VP, and LO-OX, but not in HI-OX. The results of the present study suggest that the incorporation of 1% chitosan minimizes premature browning in ground beef patties stored under AP, VP, and LO-OX. 相似文献
104.
在世界范围内,由真菌毒素造成的经济损失估计达数十亿美元,给人类和动物带来安全风险。粮食中真菌毒素的预防可以通过食品加工过程中进行真菌毒素的消减处理。在过去几十年里,虽然发表的科技论文中报道了大量真菌毒素防控措施,但实际生产往往需要更容易实施的、简单易行的建议和指导方针。欧洲和东南亚在真菌毒素处理到数据分析、风险评估到污染防控、差异分析到流通途径等方面可以做到相互协作,互相补充。欧洲和东南亚政府及相关行业必须在综合考虑地域、农业系统和不同国家消费者偏好的背景下,寻求平衡食品安全和地区贸易二者关系,协同管控食品供应链。以谷物为例,加工过程包括初级加工(谷物清理和碾磨操作)和二次加工(如烘焙过程中的发酵和烘烤),欧洲尤其关注烘焙食品安全性及全麦面包生产工艺对呕吐毒素的影响。结合农业、咖啡工业和科学研究人员的专业知识及亚洲咖啡生产者的具体情况,重点关注东南亚地区咖啡中赭曲霉毒素A污染问题。在农场环境中减少真菌毒素的措施给咖啡农民带来了较大的挑战,包括在规范种植农场模式下咖啡生产者和消费者之间社会经济效益和个人行为模式的相关影响因素。随着世界变得更加全球化,食品和饲料供应链也变得日趋复杂,因此,需要制定更全面的策略来确保食品供给及品质安全。 相似文献
105.
Garcia M Amalaradjou MA Nair MK Annamalai T Surendranath S Lee S Hoagland T Dzurec D Faustman C Venkitanarayanan K 《Journal of food protection》2007,70(7):1594-1599
The antilisterial activity of monocaprylin (MC) and its combination with acetic acid (AA) on frankfurters was investigated. Each frankfurter was surface inoculated with a three-strain mixture of Listeria monocytogenes to obtain an inoculation level of 4.0 log CFU per frankfurter, and then dipped for 35 s in sterile deionized water (45 or 50 degrees C) containing 1% ethanol (control), 50 mM MC plus 1% ethanol, 1% AA plus 1% ethanol, or 50 mM MC plus 1% AA plus 1% ethanol. Samples were vacuum packaged, stored at 4 degrees C for 77 days, and analyzed for L. monocytogenes. Sensory odor and color of frankfurters were evaluated using a 9-point hedonic scale. Color was also objectively measured using the Minolta Chroma Meter. From day 0 to day 77, population counts of L. monocytogenes on frankfurters dipped in antimicrobial solutions at 50 degrees C were consistently lower than the control counts. Similar results were observed for samples treated at 45 degrees C. However, L. monocytogenes grew readily on control samples at both temperatures. Dipping of frankfurters in antimicrobial solutions (45 or 50 degrees C) significantly reduced (P < 0.05) the populations of L. monocytogenes. After 70 days of storage, L. monocytogenes was completely killed in samples dipped in MC+AA solution at 50 degrees C. The antimicrobial treatments did not affect the odor or color of the samples (P > 0.05). Overall, results indicated that dipping of frankfurters with MC reduced L. monocytogenes, and inclusion of AA further enhanced MC antilisterial activity, without any negative effect on odor or color. 相似文献
106.
Hardy K Wright C Rice S Tachataki M Roberts R Morgan D Spanos S Taylor D 《Reproduction (Cambridge, England)》2002,123(2):171-183
The advent of human in vitro fertilization (IVF) over 30 years ago has made the oocyte and preimplantation embryo uniquely accessible. This accessibility has given rise to new micromanipulation techniques, such as intracytoplasmic sperm injection for treatment of male infertility, as well as embryo biopsy for preimplantation diagnosis of both genetic disease and aneuploidy, a major cause of early embryo demise and miscarriage. In the UK, average pregnancy rates after IVF and embryo transfer are < 25%, even after transfer of several embryos. Unfortunately, a third of these pregnancies involve multiple gestations. Research is currently focusing on methods to improve IVF success rates while reducing twin and triplet pregnancies and their associated increased morbidity and mortality. One approach is to develop screening methods to identify the most viable embryos, so that transfer of fewer healthy embryos will result in a higher proportion of singleton pregnancies. Screening methods include optimizing culture conditions for prolonged culture and selection of viable blastocysts for transfer, or embryo biopsy and aneuploidy screening. Assisted reproduction is also increasingly important in other branches of medicine: survival rates for cancer sufferers are improving continually and there is now a significant need for approaches to preserve fertility after sterilizing chemo-and radiotherapy treatment. Techniques for cryopreserving male and female gametes or gonadal tissue are being developed, although systems to grow and mature these gametes are in their infancy. Finally, there are also concerns regarding the safety of these new assisted reproductive technologies. 相似文献
107.
A series of poly(arylene ether)s ( 7a–7f ) were successfully synthesized by aromatic nucleophilic substitution reactions of imidoaryl biphenol (5), 4,9‐bis‐(4‐hydroxy‐phenyl)‐2‐phenyl‐benzo[f]isoindole‐1,3‐dione with six different trifluoromethyl substituted bisfluoro monomers ( 6a–6f ). The weight‐average molar masses of the polymers were up to 280 kD as measured by GPC. These poly(arylene ether)s exhibited glass transition temperatures up to 361°C in DSC. These polymers showed very high thermal stability up to 558°C for 10% weight loss under synthetic air in TGA. Except 7d–7f, remaining polymers 7a–7c were soluble in a wide range of organic solvents. Transparent thin films of these polymers cast from DCM or NMP exhibited tensile strengths up to 75 MPa and elongation at break up to 41% depending on their exact repeating unit structures. These poly(arylene ether)s showed cut‐off wavelength in between 400 and 450 nm except 7d and water absorption were in the range of 0.4 to 0.6%. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
108.
T. P. Ahammed Shabeer V. T. Gajbhiye Suman Gupta K. M. Manjaiah Eldho Varghese 《Polycyclic Aromatic Compounds》2013,33(4):452-467
Water treatment process involving simultaneous action of adsorption on different nano and organo-modified nano-clays followed by coagulation-flocculation by alum and poly aluminium chloride (PAC) has been evaluated for the removal of PAHs (naphthalene, acenaphthalene, phenanthrene, fluoranthene, anthracene, and pyrene) from water. When clay minerals along with alum and PAC were used for treatment, 37.4–100.0% removal of PAHs was observed compared to 20–38% removal using normal water treatment process with either alum or alum + PAC. The effectiveness of clay minerals for removal of PAHs followed the order (P < 0.05): halloysitenano-clay (HN-clay) < normal bentonite (NB-clay) < hydrophilic nano-bentonite (HNB-clay) < nano-montmorillonite modified with dimethyl dialkyl amine (DMDA-M-clay) ≈ nano-montmorillonite modified with octadecylamine and aminopropyltriethoxysilane (ODAAPS-M-clay) ≈ nano-montmorillonite modified with octadecylamine (ODA-M-clay) in combination with alum + PAC. The modified treatment process (alum + PAC + clay minerals), where water was initially treated with clays followed by normal process of coagulation (alum + PAC), was found to be the most effective method with maximum removal for ODAAPS-M-clay (97.7–100.0%) which is at par wih ODA-M (97.0–100.0%), and DMDA-M-clay (94.8–100%). The removal of PAHs varied in the order: naphthalene ≈ acenaphthalene > anthracene ≈ pyrene > phenanthrene > fluoranthrene. The treatment combination having the maximum removal capacity was also used eficiently for the removal of PAHs from natural and fortified natural water. This article demonstrated adsorption-coagulation integrated system has the potential to remediate PAHs polluted water. 相似文献
109.
Suman Mukherjee John Federici Paulo Lopes Miguel Cabral 《Journal of Infrared, Millimeter and Terahertz Waves》2013,34(9):539-555
For the past few decades there has been tremendous innovation and development of Terahertz (THz) science and imaging. In particular, the technique of 3-D computed tomography has been adapted from the X-Ray to the THz range. However, the finite refractive index of materials in the THz range can severally refract probing THz beams during the acquisition of tomography data. Due to Fresnel reflection power losses at the boundaries as well as steering of the THz beam through the sample, refractive effects lead to anomalously high local attenuation coefficients near the material boundaries of a reconstructed image. These boundary phenomena can dominate the reconstructed THz-CT images making it difficult to distinguish structural defect(s) inside the material. In this paper an algorithm has been developed to remove the effects of refraction in THz-CT reconstructed images. The algorithm is successfully implemented on cylindrical shaped objects. 相似文献
110.
21st Century is treated as the century for highly branched macromolecules, because of their unique structural architecture and outstanding performance characteristics, in the field of polymer science. In the present study, castor oil-based two hyperbranched polyurethanes (HBPUs) were synthesized via A2 + B3 approach using castor oil or monoglyceride of the castor oil as the hydroxyl containing B3 reactant and toluene diisocyanate (TDI) as an A2 reactant along with 1,4-butane diol (BD) as the chain extender and poly(?-caprolactone) diol (PCL) as a macroglycol. The adopted ‘high dilution and slow addition’ technique offers hyperbranched polymers with high yield and good solubility in most of the polar aprotic solvents. Fourier transforms infra-red spectroscopy (FTIR) and nuclear magnetic resonance (NMR) analyses confirmed the chemical structure of synthesized polymers, while wide angle X-ray diffraction (WXRD) and scanning electron microscope (SEM) resulted the insight of their physical structures. The degree of branching was calculated from 1H NMR and found to be 0.57 for castor oil based hyperbranched polyurethane (CHBPU), while it was 0.8 for monoglyceride based hyperbranched polyurethane (MHBPU). The studies showed that MHBPU and CHBPU exhibited tensile strength 11 MPa and 7 MPa, elongation at break 695% and 791%, scratch hardness 5 kg and 4.5 kg, gloss 84 and 72, respectively. Thermal properties like thermo stability, melting point, enthalpy, degree of crystallinity and glass transition temperature (Tg); and chemical resistance in different chemical media were found to be almost equivalent for both the polyurethanes. The measurements of dielectric constant and lost factor indicated that both the HBPUs behave as dielectric materials. Thus the synthesized HBPUs have the potential to be used as advanced surface coating materials. 相似文献