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41.
David S Himmelsbach Sadia Khalili Danny E Akin 《Journal of the science of food and agriculture》2002,82(7):685-696
Fourier transform infrared (FT‐IR) microspectroscopic mapping was investigated as a tool to study the effects of enzymatic retting of flax stems. The FT‐IR technique permitted the elucidation of the relative loss or changes in the distribution of key chemical components after treatment with enzymes or enzyme/chelator mixtures in association with visible changes in structure. Cross‐sections of Ariane flax stems were treated with SP 249 (a pectinase‐rich enzyme mixture from Novo Nordisk) at 0.5, 0.7 or 1.0 ml l?1 concentration in pH 5 acetate buffer for 6 h at 40 °C. Flax stems treated with 0.5 or 0.7 ml l?1 SP 249 and 50 mM oxalic acid as a chelator were also investigated by the technique. The results indicated that treatment with 0.5 ml l?1 SP 249 alone was ineffective in releasing the fibre bundles from the surrounding tissue, but the release was increased by the addition of 50 mM oxalic acid as a likely chelator for the cations of pectate salts. However, the IR spectra of the bundles indicated that an insoluble oxalate salt remained on the tissue after this treatment. Increasing the concentration of SP 249 to 0.7 ml l?1 plus 50 mM oxalic acid was effective in releasing the fibre bundles and generating some ultimate fibres with no detectable oxalate expectate salt residues. Increasing the SP 249 concentration to 1.0 ml l?1 without using oxalic acid was effective in separating the fibre bundles into ultimate (individual) fibres, leaving no pectate salt residue and only a trace of pectic esters and/or acids. The use of infrared mapping, or so‐called chemical imaging, is shown to have advantages over visible imaging alone in that it can detect and locate the chemical species present after each treatment in relation to the anatomical features of the flax stem. This analytical tool shows promise as a technique by which to study the effects of enzymatic treatment of natural fibre materials. Published in 2002 for SCI by John Wiley & Sons, Ltd 相似文献
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Aspergillus niger was subjected to UV radiation and chemical mutagenesis to develop its hyper-producing mutants for enhanced citric acid production. Ethyl methane sulfonate (EMS) and Ethidium bromide (EB) were used for chemical mutagenesis of Aspergillus niger. UV, and chemically treated mutants of Aspergillus niger were identified by using 2-deoxy, D-glucose as selective marker. The selected mutants were cultured in solid state fermentation (SSF) of sugarcane molasses medium (10%) using corn cobs, banana stalk, sugarcane bagasse, wheat straw, and wheat bran as carrier substrates. After pH adjustment and sterilization, the triplicate flasks were inoculated with 5 mLof homogenous spore suspensions of selected mutants of A. niger and the flasks were subjected to SSF under still culture conditions. The mutant EB-3 (treated with 1 mg/mL ethidium bromide for 120 min) giving highest citric acid yield (64.2 mg/mL) in 72 h was selected as hyper-producing mutant. Citric acid production process using EB-3 mutant was then optimized to enhance citric acid production by the mutant in SSF. Aspergillus niger EB-3 mutant could produce 67.72 mg/mL citric acid in 72 h using banana stalks as support material under optimum conditions of pH (pH 6), incubation temperature (35°C) and inoculum size (5 mL) in SSF. 相似文献
44.
Objective: The authors sought to evaluate the association of self-efficacy with objective measures of cardiac function, subsequent hospitalization for heart failure (HF), and all-cause mortality. Design: Observational cohort of ambulatory patients with stable CHD. The authors measured self-efficacy using a published, validated, 5-item summative scale, the Sullivan Self-Efficacy to Maintain Function Scale. The authors also performed a cardiac assessment, including an exercise treadmill test with stress echocardiography. Main Outcome Measures: Hospitalizations for HF, as determined by blinded review of medical records, and all-cause mortality, with adjustment for demographics, medical history, medication use, depressive symptoms, and social support. Results: Of the 1,024 predominately male, older CHD patients, 1013 (99%) were available for follow-up, 124 (12%) were hospitalized for HF, and 235 (23%) died during 4.3 years of follow-up. Mean cardiac self-efficacy score was 9.7 (SD 4.5, range 0–20), corresponding to responses between “not at all confident” and “somewhat confident” for ability to maintain function. Lower self-efficacy predicted subsequent HF hospitalization (OR per SD decrease = 1.4, p = .0006), and all-cause mortality (OR per SD decrease = 1.4, p Conclusion: Among patients with CHD, self-efficacy was a reasonable proxy for predicting HF hospitalizations. The increased risk of HF associated with lower baseline self-efficacy was explained by worse cardiac function. These findings indicate that measuring cardiac self-efficacy provides a rapid and potentially useful assessment of cardiac function among outpatients with CHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Haleema Sadia Muhammad Zafar Mushtaq Ahmad Lubna Muhammad P. Z. Khan Ghulam Yaseen Muhammad I. Ali Shazia Sultana Omer Kilic Zeynep ahan Naveed Alam Qamar Abbas Abdul Ghani Saeeda Naz 《Microscopy research and technique》2020,83(3):259-267
The present study is focused on the detailed foliar epidermal anatomy of some selected wild edible fruits (WEFs) from Pakistan using light microscopy (LM) and scanning electron microscopy (SEM). The studied species are Ficus racemosa L., Solanum nigrum L., Capparis spinosa L., Physalis divaricata D.Don, Rosa moschata Herrm. and Ribes orientale Desf. collected from various localities of Pakistan. The objective of the present study is to investigate qualitative and quantitative anatomical characters for the identification and differentiation of collected wild edible fruits. The characters studied are shape and size of epidermal cells, anticlinal wall pattern, trichome type and shape, average number of stomata, length and width of stomata and pore. The detailed microscopic investigation and variations in the characters recorded have a key role in the determination and authentication of wild edible fruits. This study possesses great potential for plant taxonomists to further evaluate the species at molecular and genetic levels. 相似文献
46.
Effat Sitara Habib Nasir Asad Mumtaz Muhammad Fahad Ehsan Manzar Sohail Sadia Iram Syeda Aqsa Batool Bukhari Sharif Ullah Tehmina Akhtar Azhar Iqbal 《International Journal of Hydrogen Energy》2021,46(50):25424-25435
The objective of this research is to construct a type-II heterojunction interface for effective photoelectrochemical (PEC) water splitting for hydrogen generation. A series of ZnSe/g-C3N4 heterojunctions is prepared by ultrasonication procedure and tested for PEC water splitting for the first time. The successful formation of ZnSe/g-C3N4 is confirmed by phase, morphological and optical analysis. Linear sweep voltammetry of 0.05 ZG (0.05% ZnSe/g-C3N4) showed a six-fold higher photocurrent density of 500 μA than g-C3N4. These results are supported by the Tafel slopes and PL (photoluminescence spectroscopy) studies by showing the smallest slope and lesser electron-hole recombination for 0.05 ZG. Increased lifetime of 107 ms and a higher donor density of 3.6 × 1019 cm?3 for 0.05 ZG is observed. The smallest semicircle for 0.05 ZG in EIS implies the least charge transfer resistance among the prepared heterojunctions. All the results comply with each other showing the successful formation of type-II heterojunction for enhanced PEC water splitting. 相似文献
47.
Maurizio Battino Tamara Y. Forbes-Hernández Massimiliano Gasparrini Sadia Afrin Danila Cianciosi Jiaojiao Zhang 《Critical reviews in food science and nutrition》2019,59(6):893-920
AbstractThe traditional Mediterranean diet (MedDiet) is a well-known dietary pattern associated with longevity and improvement of life quality as it reduces the risk of the most common chronic pathologies, such as cancer and cardiovascular diseases (CVDs), that represent the principal cause of death worldwide. One of the most characteristic foods of MedDiet is olive oil, a very complex matrix, which constitutes the main source of fats and is used in the preparation of foods, both raw as an ingredient in recipes, and in cooking. Similarly, strawberries and raspberries are tasty and powerful foods which are commonly consumed in the Mediterranean area in fresh and processed forms and have attracted the scientific and consumer attention worldwide for their beneficial properties for human health. Besides olive oil and berries, honey has lately been introduced in the MedDiet thanks to its relevant nutritional, phytochemical and antioxidant profile. It is a sweet substance that has recently been classified as a functional food. The aim of this review is to present and discuss the recent evidence, obtained from in vitro, in vivo and epidemiological studies, on the potential roles exerted by these foods in the prevention and progression of different types of cancer and CVDs. 相似文献
48.
Permeabilities of cast films of methylmethacrylate-co-methacrylic acid (MMA—MAA) and its 5% neutralized Na1+, CS1+, Zn2+, Ba2+, and Al3+ ionomers for urea, sodium chloride, and creatinine were determined using a double (donor and acceptor) compartment cell. Film permeability was increased as the ionic potential decreased and it was more marked with urea as compared with sodium chloride and creatinine. Tensile properties of the above samples were also tested and variations in Young's Moduli were based on the effect of type of aggregates produced by the cations in the matrix of the copolymer. © 1993 John Wiley & Sons, Inc. 相似文献
49.
Software Quality Journal - To survive in competitive marketplaces, most organizations have adopted agile methodologies to facilitate continuous integration and faster application delivery and rely... 相似文献
50.
Mubashar Hussain Mansoor Ahmed Hasan Ali Khattak Muhammad Imran Abid Khan Sadia Din Awais Ahmad Gwanggil Jeon Alavalapati Goutham Reddy 《The Journal of supercomputing》2018,74(10):5003-5021
Web content filtering is one among many techniques to limit the exposure of selective content on the Internet. It has gotten trivial with time, yet filtering of multilingual web content is still a difficult task, especially while considering big data landscape. The enormity of data increases the challenge of developing an effective content filtering system that can work in real time. There are several systems which can filter the URLs based on artificial intelligence techniques to identify the site with objectionable content. Most of these systems classify the URLs only in the English language. These systems either fail to respond when multilingual URLs are processed, or over-blocking is experienced. This paper introduces a filtering system that can classify multilingual URLs based on predefined criteria for URL, title, and metadata of a web page. Ontological approaches along with local multilingual dictionaries are used as the knowledge base to facilitate the challenging task of blocking URLs not meeting the filtering criteria. The proposed work shows high accuracy in classifying multilingual URLs into two categories, white and black. Evaluation results conducted on a large dataset show that the proposed system achieves promising accuracy, which is on a par with those achieved in state-of-the-art literature on semantic-based URL filtering. 相似文献