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71.
Enns AA Vogel LJ Abdelzaher AM Solo-Gabriele HM Plano LR Gidley ML Phillips MC Klaus JS Piggot AM Feng Z Reniers AJ Haus BK Elmir SM Zhang Y Jimenez NH Abdel-Mottaleb N Schoor ME Brown A Khan SQ Dameron AS Salazar NC Fleming LE 《Water research》2012,46(7):2237-2246
Fecal indicator microbes, such as enterococci, are often used to assess potential health risks caused by pathogens at recreational beaches. Microbe levels often vary based on collection time and sampling location. The primary goal of this study was to assess how spatial and temporal variations in sample collection, which are driven by environmental parameters, impact enterococci measurements and beach management decisions. A secondary goal was to assess whether enterococci levels can be predictive of the presence of Staphylococcus aureus, a skin pathogen. Over a ten-day period, hydrometeorologic data, hydrodynamic data, bather densities, enterococci levels, and S. aureus levels including methicillin-resistant S. aureus (MRSA) were measured in both water and sand. Samples were collected hourly for both water and sediment at knee-depth, and every 6 h for water at waist-depth, supratidal sand, intertidal sand, and waterline sand. Results showed that solar radiation, tides, and rainfall events were major environmental factors that impacted enterococci levels. S. aureus levels were associated with bathing load, but did not correlate with enterococci levels or any other measured parameters. The results imply that frequencies of advisories depend heavily upon sample collection policies due to spatial and temporal variation of enterococci levels in response to environmental parameters. Thus, sampling at different times of the day and at different depths can significantly impact beach management decisions. Additionally, the lack of correlation between S. aureus and enterococci suggests that use of fecal indicators may not accurately assess risk for some pathogens. 相似文献
72.
Sandip Ghosh Deb Mukhopadhyay Samir Kumar Saha 《International Journal of Pressure Vessels and Piping》2011,88(8-9):281-289
The work presented here is an experimental investigation of the critical flashing flow of initially subcooled water through circumferential slits in pipes. The study provides first hand information about the prediction of leak flow rates in piping and pressure vessels retaining high temperature and high pressure. The dedicated experimental facility loop simulates the thermal hydraulic condition of Pressurized Heavy Water Reactors (PHWR). The critical flow characteristics found for varying leakage cross sections at different stagnation pressure and different degree of subcooling has been demonstrated in this paper. A marked decrease in mass flux has been found as subcooling decreases for a fixed stagnation pressure. More observation has revealed that the tighter slits or openings with very short duct as small as 0.8 cm flow length have different flow behavior than greater opening dimensions or with longer flow channels or that for nozzles. The critical flow has been seen to occur at higher pressure differentials along the flaws and prominent changes in the flow rate is reported to occur with varying dimensional parameters of the slit or cracks. 相似文献
73.
Ria Ghosh Soumendra Singh Dipanjan Mukherjee Susmita Mondal Monojit Das Uttam Pal Aniruddha Adhikari Aman Bhushan Surajit Bose Siddharth Sankar Bhattacharyya Debasish Pal Tanusri Saha-Dasgupta Maitree Bhattacharyya Debasis Bhattacharyya Asim Kumar Mallick Ranjan Das Samir Kumar Pal 《Chembiochem : a European journal of chemical biology》2022,23(9):e202200109
Drug delivery to a target without adverse effects is one of the major criteria for clinical use. Herein, we have made an attempt to explore the delivery efficacy of SDS surfactant in a monomer and micellar stage during the delivery of the model drug, Toluidine Blue (TB) from the micellar cavity to DNA. Molecular recognition of pre-micellar SDS encapsulated TB with DNA occurs at a rate constant of k1 ∼652 s−1. However, no significant release of encapsulated TB at micellar concentration was observed within the experimental time frame. This originated from the higher binding affinity of TB towards the nano-cavity of SDS at micellar concentration which does not allow the delivery of TB from the nano-cavity of SDS micelles to DNA. Thus, molecular recognition controls the extent of DNA recognition by TB which in turn modulates the rate of delivery of TB from SDS in a concentration-dependent manner. 相似文献
74.
Ledmi Makhlouf Zidat Samir Hamdi-Cherif Aboubekeur 《Knowledge and Information Systems》2021,63(7):1873-1908
Knowledge and Information Systems - Mining itemsets for association rule generation is a fundamental data mining task originally stemming from the traditional market basket analysis problem.... 相似文献
75.
Samir Attafi Aklouche-benouaguef Sabiha TALAŞ Şükrü 《Protection of Metals and Physical Chemistry of Surfaces》2021,57(4):786-795
Protection of Metals and Physical Chemistry of Surfaces - The AA6061-T6 alloy is used in many industrial applications such as hydraulic pistons, aerospace and marine vehicle fittings, including the... 相似文献
76.
Salsabeel N. El Gendy Amira K. Elmotayam Reham Samir Marwa I. Ezzat Aly M. El Sayed 《Journal of the American Oil Chemists' Society》2023,100(8):591-614
Simmondsia chinensis (Link) C.K. Schneider (Jojoba) is a valuable shrub that can bear harsh conditions and is cultivated in many countries globally. Its prominence originates from the unique oil that constitutes more than 50% of the seeds. The great economic value of jojoba oil is highlighted in many fields, especially the cosmetic industry. The remaining meal, which is rich in proteins, constitutes a good source for cattle feeding. However, the presence of antinutritional principles in the meal limited its use and encouraged the researchers to find different ways for its detoxification. The detoxification ways of jojoba meal included physical, biological, and chemical treatments. The phytochemical composition of the oil was deeply studied, but for the remaining plant, only few studies have reported its chemical composition. Jojoba oil composed of wax esters (97%), fatty acids, fatty alcohols, sterols, and small percentage of vitamin E. Jojoba possesses a long traditional history. It has been used in folklore for treatment of cold, dysuria, and obesity. Many recent studies reported its medicinal and pharmacological properties like antioxidant, anti-inflammatory, antimicrobial, anticancer, anti-acne, anti-psoriasis, wound healing, and hepatoprotective activities. Many of these biological activities have been attributed to the presence of several phytochemicals such as simmondsin and phenolic compounds. In this review, the authors will highlight the previous phytochemical studies, medicinal applications of jojoba oil and different plant parts, and the various ways of meal detoxification. 相似文献
77.
In this paper, we present a concern-based technique for software architecture modelling. We use the new UML 2 Package Merge relationship as a technique for the separation of concerns. We present the advantages of using the UML Package Merge relationship for software architecture modelling, and we propose a set of extensions for its limitations. 相似文献
78.
In this work, a gamma ray Compton backscatter technique is used for imaging defects and thickness variations in insulated pipes and metal plates containing depressions of various diameters and at various depths from one side of the object. The scattered radiation was measured by a scintillation detector that scans the object using a two-dimensional mechanical scanning system. The gamma spectrum was displayed with a multichannel analyzer (MCA), and the energy window width was selected so that only Compton single scatter counts were measured. Images were constructed using the LabVIEW computer program. Successful images of defects on the outer surface of the object under the insulation were obtained, and the system was found to be able to detect wall thickness changes in large pipes with walls more than 15 mm thick. Low activity sources of 108 Bq (a few mCi) were used, and the dose rate near the surface is four orders of magnitude lower than conventional industrial radiography sources, permitting it to be much safer. 相似文献
79.
The present brief account relates synthetic endeavours revolving around a novel chemistry of xanthates (dithiocarbonates) being developed in our group. The degenerative reversible transfer of xanthates has a unique ability to store reactive radicals in a dormant form, and thereby to enhance their lifetime in a concentrated medium, while at the same time, regulating their absolute and relative concentrations. It allows intermolecular radical additions even to unactivated alkenes, and can promote otherwise sluggish radical processes, such as 5-endo, 6-exo, 6-endo, 7-endo, and 8-endo cyclisations, as well as ring closures on (hetero)aromatic structures. This chemistry has proved remarkably versatile and powerful, both for solving synthetic problems and for the industrial production of block copolymers through the RAFT/MADIX technology. 相似文献
80.
Summary This paper is concerned with business mortality analysis in a Bayesian setting. We assume that a businessman startsN businesses at different points of time and at a certain epoch referred to as the ‘present’, the failure times of the failed
businesses and the survival times of the still surviving businesses are recorded. Bayesian prediction for business mortality
or survival up to a future time pointt
0 is made under the assumptions of a Weibull business survival distribution (WBSD) and the squared error loss function (SELF).
The results are extended to the situation where one of the observed times of business failure may possibly be an outlier. 相似文献