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991.
992.
Luke Aiden Westfall Julia Davourie Mohammed Ali Doreen McGough 《The International Journal of Life Cycle Assessment》2016,21(11):1573-1579
Purpose
Manganese is a metal used extensively in everyday life, particularly in structural steel. Despite the importance of manganese as an essential alloying element in steel and stainless steel, the environmental profile of manganese alloys lacked globally representative, primary industry data. The International Manganese Institute (IMnI) and Hatch completed the first global life cycle assessment (LCA) of manganese alloy production, providing environmental benchmarks and a firm foundation of accurate data with which to inform other industry-led initiatives.Methods
The study compiled primary data from 16 ore and alloy producers worldwide, covering 18 % of global ore production and 8 % of global alloy production for 2010. This peer-reviewed, ISO 14040 compliant LCA covers the cradle-to-gate life cycles of silicomanganese, ferromanganese, and refined ferromanganese. The study provides a comprehensive picture of global environmental performance, quantifying energy consumption, global warming potential (GWP), acidification potential (AP), photochemical ozone creation potential (POCP), primary water use, and primary waste generation. A novel model architecture was devised to generate process, site, and cradle-to-gate LCAs for single and multiple sites simultaneously, extracting greater value from the LCA process by facilitating environmental and operational benchmarking within the industry.Results and discussion
The results of the study show that total GWP, AP, and POCP for 1 kg of average manganese alloy was 6.0 kg CO2e, 45 g SO2e, and 3 g C2H4e, respectively. Electricity demand and coal and coke consumption during smelting are the dominant operating parameters contributing to environmental performance. On-site air emission measures (GWP, POCP, NOX, and particulate matter (PM)) contributed 25 to 35 % of total life cycle emissions. Overburden and waste rock were the most significant primary solid waste flows by mass. The study provides a resource for improvement at the global industry and site scales by establishing benchmarks, identifying hotspots, and quantifying the benefits of efficiency savings through process optimization.Conclusions
This LCA provides accurate primary data to improve steel and stainless steel product LCAs and communicate the environmental performance of the industry in quantitative terms. It facilitates dialogue between manganese producers and consumers through a shared understanding of the environmental profile of the industry. Through leveraging the study to identify hotspots within the manganese supply chain, producers can work both independently and collectively towards improving the environmental and economic performance of manganese alloys.993.
Validated spectrofluorimetric method for determination of two phosphodiesterase inhibitors tadalafil and vardenafil in pharmaceutical preparations and spiked human plasma
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Mohammed Abu Bakr Abu El‐Enin Mohammed El‐Sayed Abd Al‐Ghaffar Hammouda Dina Tawfik El‐Sherbiny Dalia Rashad El‐Wasseef Saadia Mahmoud El‐Ashry 《Luminescence》2016,31(1):173-178
A valid, sensitive and rapid spectrofluorimetric method has been developed and validated for determination of both tadalafil (TAD) and vardenafil (VAR) either in their pure form, in their tablet dosage forms or spiked in human plasma. This method is based on measurement of the native fluorescence of both drugs in acetonitrile at λem 330 and 470 nm after excitation at 280 and 275 nm for tadalafil and vardenafil, respectively. Linear relationships were obtained over the concentration range 4–40 and 10–250 ng/mL with a minimum detection of 1 and 3 ng/mL for tadalafil and vardenafil, respectively. Various experimental parameters affecting the fluorescence intensity were carefully studied and optimized. The developed method was applied successfully for the determination of tadalafil and vardenafil in bulk drugs and tablet dosage forms. Moreover, the high sensitivity of the proposed method permitted their determination in spiked human plasma. The developed method was validated in terms of specificity, linearity, lower limit of quantification (LOQ), lower limit of detection (LOD), precision and accuracy. The mean recoveries of the analytes in pharmaceutical preparations were in agreement with those obtained from the comparison methods, as revealed by statistical analysis of the obtained results using Student's t‐test and the variance ratio F‐test. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
994.
Heba M. Aboud Mohammed H. El komy Adel A. Ali Shahira F. El Menshawe Ahmed Abd Elbary 《AAPS PharmSciTech》2016,17(6):1353-1365
Carvedilol, a beta-adrenergic blocker, suffers from poor systemic availability (25%) due to first-pass metabolism. The aim of this work was to improve carvedilol bioavailability through developing carvedilol-loaded solid lipid nanoparticles (SLNs) for nasal administration. SLNs were prepared by emulsion/solvent evaporation method. A 23 factorial design was employed with lipid type (Compritol or Precirol), surfactant (1 or 2% w/v poloxamer 188), and co-surfactant (0.25 or 0.5% w/v lecithin) concentrations as independent variables, while entrapment efficiency (EE%), particle size, and amount of carvedilol permeated/unit area in 24 h (Q 24) were the dependent variables. Regression analysis was performed to identify the optimum formulation conditions. The in vivo behavior was evaluated in rabbits comparing the bioavailability of carvedilol after intravenous, nasal, and oral administration. The results revealed high drug EE% ranging from 68 to 87.62%. Carvedilol-loaded SLNs showed a spherical shape with an enriched core drug loading pattern having a particle size in the range of 66 to 352 nm. The developed SLNs exhibited significant high amounts of carvedilol permeated through the nasal mucosa as confirmed by confocal laser scanning microscopy. The in vivo pharmacokinetic study revealed that the absolute bioavailability of the optimized intranasal SLNs (50.63%) was significantly higher than oral carvedilol formulation (24.11%). Hence, we conclude that our developed SLNs represent a promising carrier for the nasal delivery of carvedilol. 相似文献
995.
James R. Priest Kazutoyo Osoegawa Nebil Mohammed Vivek Nanda Ramendra Kundu Kathleen Schultz Edward J. Lammer Santhosh Girirajan Todd Scheetz Daryl Waggott Francois Haddad Sushma Reddy Daniel Bernstein Trudy Burns Jeffrey D. Steimle Xinan H. Yang Ivan P. Moskowitz Matthew Hurles Richard P. Lifton Debbie Nickerson Michael Bamshad Evan E. Eichler Seema Mital Val Sheffield Thomas Quertermous Bruce D. Gelb Michael Portman Euan A. Ashley 《PLoS genetics》2016,12(4)
996.
Ishfaq A. Sheikh Muhammad Yasir Muhammad Abu-Elmagd Tanveer A. Dar Adel M. Abuzenadah Ghazi A. Damanhouri Mohammed Al-Qahtani Mohd A. Beg 《BMC structural biology》2016,16(1):15
Background
Currently, alternate plasticizers are used to replace phthalate plasticizers in children’s toys, medical equipments and food packaging, due to the adverse effects of phthalate compounds on human health and laws prohibiting their use. Current information regarding the safety and potential adverse effects of alternate plasticizers is limited and recent studies have found alternate plasticizers to display similar characteristics to those observed in phthalate plasticizers. This study was undertaken to evaluate and predict the potential endocrine disrupting activity of the three most commonly used alternate plasticizers: di(2-ethylhexyl)terephthalate (DEHT), tris(2-ethylhexyl)trimellitate (TOTM), and diisononyl hexahydrophthalate (DINCH) against human sex hormone-binding globulin (SHBG) using in silico approaches.Materials and methods
The crystal structure of human SHBG (Id: 1D2S) was retrieved from Protein Data Bank. PubChem database was searched for the structures of alternate plasticizers, DEHT, TOTM, and DINCH. Docking was performed using Glide (Schrodinger) Induced Fit Docking module.Results
Induced Fit Docking of three alternate plasticizer compounds indicated that each of the three compounds fitted well into the steroid binding pocket of SHBG. Docking displays showed interactions of alternate plasticizers with 25–30 amino-acid residues of SHBG; 18–20 amino residues overlapped between the natural ligand, DHT, and the three compounds (commonality of 82–91 %). The hydrogen-bonding interaction of the amino-acid residue, Asn-82, of SHBG was also present in displays of DHT and all the three alternate phthalates. The binding affinity of all the three alternate phthalates was higher than DHT; maximum in DINCH followed by TOTM and DEHT.Conclusion
Our results suggested that the three alternate plasticizers have potential to engage the important interacting residues of SHBG and thus interfere in its steroid homeostatic function.997.
Sonia Del Prete Viviana De Luca Daniela Vullo Sameh M. Osman Zeid AlOthman Vincenzo Carginale 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):1156-1161
Malassezia yeasts are almost exclusively the single eukaryotic members of the fungal flora of the skin. Malassezia globosa and Malassezia restricta are found on the skin of practically all humans. Malassezia globosa is highly implicated in the pathogenesis of dandruff and its genome encodes for only one carbonic anhydrases (CAs, EC 4.2.1.1) belonging to the β-class (MgCA). It has been indeed demonstrated that in many pathogenic microorganisms, CAs are essential for their life cycle and their inhibition can lead to growth impairment and defects. In the previous work, the recombinant MgCA was investigated for its inhibition profile with sulfonamides, which in models of dandruff infection were able to protect animals from the fungal infection, allowing us to propose this enzyme as a new antidandruff target. MgCA was cloned as GST-fusion protein, but the yield was rather low and the protein was often found in inclusion bodies. Here, we propose an alternative procedure consisting in cloning the recombinant MgCA as His-Tag fusion protein. This procedure resulted in a good method to express and purify the active recombinant MgCA, and the protein recovery was better with respect to that used for preparing MG-CA (β-CA cloned as GST-fusion protein). 相似文献
998.
999.
Corina Shtir Mohammed A. Aldahmesh Saad Al-Dahmash Emad Abboud Hisham Alkuraya Marwan A. Abouammoh Sawsan R. Nowailaty Ghazai Al-Thubaiti E. A. Naim B. ALYounes F. S. Binhumaid A. B. ALOtaibi A. S. Altamimi F. H. Alamer Mais Hashem Mohamed Abouelhoda Dorota Monies Fowzan S. Alkuraya 《Human genetics》2016,135(2):193-200
1000.
Minhaz Uddin Ahmed Mohammad Mosharraf Hossain Mohammadali Safavieh Yen Lu Wong Ibrahim Abd Rahman Mohammed Zourob 《Critical reviews in biotechnology》2016,36(3):495-505
Screen printing technology provides a cheap and easy means to fabricate disposable electrochemical devices in bulk quantities which are used for rapid, low-cost, on-site, real-time and recurrent industrial, pharmaceutical or environmental analyses. Recent developments in micro-fabrication and nano-characterization made it possible to screen print reproducible feature on materials including plastics, ceramics and metals. The processed features forms screen-printed disposable biochip (SPDB) upon the application of suitable bio-chemical recognition receptors following appropriate methods. Adequacy of biological and non-biological materials is the key to successful biochip development. We can further improve recognition ability of SPDBs by adopting new screen printed electrode (SPE) configurations. This review covers screen-printing theory with special emphasis on the technical impacts of SPE architectures, surface treatments, operational stability and signal sensitivity. The application of SPE in different areas has also been summarized. The article aims to highlight the state-of-the-art of SPDB at the laboratory scale to enable us in envisaging the deployment of emerging SPDB technology on the commercial scale. 相似文献