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41.
42.
Hurst AM Edwards MJ Chipps M Jefferson B Parsons SA 《The Science of the total environment》2004,321(1-3):219-230
This paper examines turbidity removal at a water treatment works in England that receives raw water which is difficult to treat during certain rainstorm events. Rainstorm events lead to elevated levels of turbidity and organic matter found in river waters. A robustness index based on settled turbidity was used to identify periods and events that adversely affected the treatment process. This coupled with raw water sampling data indicated that a change in nature and an increase in natural organic matter (NOM) concentrations occurred following rainstorm events. Experimental work investigated the effect of temperature and NOM on the coagulation process and the results show how increasing levels of NOM significantly impaired the coagulation of particulate material, leading to an increase in settled turbidity. 相似文献
43.
PE Goodacre 《International Journal of Project Management》1983,1(1):29-31
The structure and philosophy of a one-year course in construction management are described. Emphasis is placed on the importance of forgetting old methods and ideas, in order to take full advantage of new technologies, and on the need to allow enough time for effective training. 相似文献
44.
45.
Mahoney PM Hurst PR McLeod BJ McConnell MA Thompson EG 《Reproduction (Cambridge, England)》2003,125(5):733-741
Mast cell populations in the vaginal cul-de-sac of female brushtail possums do not appear to be related to microbial invasion but changes in their density occur at oestrus, indicating a hormonal influence. The present study examined the effect of treatment with oestradiol on microflora and on mast cell numbers and their spatial location in cul-de-sac tissue of seasonally anoestrous brushtail possums. Tissue was collected from seasonally anoestrous brushtail possums (n = 6 per group) that were either untreated (anoestrous group) or were subjected to 6 days of treatment with oestradiol (oestradiol group) administered via subcutaneous implants or with the oil vehicle alone (control group). Tissue was collected aseptically for microbiological procedures and the fractionator and optical disector were used to quantify mast cell populations. Microflora populations were low (< 4.0 x 10(4) organisms g(-1)) and numbers of mast cells were similar in all groups. Mast cell density was greatest in epithelial and connective tissues from seasonally anoestrous and control animals and lowest in oestradiol-treated possums, in which there was a significant increase in cul-de-sac mass and volume. There is an inverse relationship between circulating oestrogen concentrations and mast cell density in possum cul-de-sac tissue, which is probably the result of an increase in tissue volume. 相似文献
46.
FS Chen PE Di Cesare AA Kale JF Lee VH Frankel SA Stuchin JD Zuckerman 《Canadian Metallurgical Quarterly》1998,13(8):867-873
We have developed a computer program for the rapid assessment of the primary structure differences between a protein of unknown sequence and a homologous known protein. Both proteins are reduced, alkylated, and digested with the same hydrolytic agent. The unfractionated peptide mixtures are submitted to automatic sequence analysis. Based on the knowledge of the reference sequence, the program utilizes the analysis data to identify all the potential peptides present in the two mixtures, determining their primary structure, homology degree, and molecular weight calculated both as integer MH+ and average mass variables. These fingerprints allow the user to easily identify the structural differences between the two proteins and clarify possible doubts by a mass spectrometric analysis of the two mixtures. In order to verify the utility of the program, we provide an application example using the already reported data of two homologous proteins. 相似文献
47.
An analog adaptive decision-feedback equalizer (DFE) is described. The DFE cancels intersymbol interference using four feedback taps, and a fifth tap cancels dc offset. The coefficient for each tap is adapted using a small mixed-signal integrator. The DFE dissipates 220 mW at a data rate of 150 Mb/s. The active area is 1.8 mm2 in a 1-μm CMOS process 相似文献
48.
The Yersinia pseudotuberculosis invasin protein is a 986-amino acid protein that promotes bacterial penetration into mammalian cells by avidly binding multiple beta 1-chain integrins. A 192-amino acid carboxyl-terminal domain of invasin was previously shown to be sufficient for binding. Evidence is presented here that a 76-amino acid disulfide loop in the integrin binding domain of invasin is required for invasin-mediated cell binding and entry. Bacterial mutants that were altered at either of 2 cysteine residues in the binding domain of invasin were completely defective for entry. Purified invasin protein derivatives altered at either of these cysteines, in contrast to the wild-type invasin, did not promote either cell binding or penetration. Analysis of proteolytic products of invasin in the presence or absence of reducing agent provided evidence of an intra-chain disulfide bond near the carboxyl terminus of the protein. Alkylation of invasin derivatives with [3H]iodoacetate indicated that these 2 cysteines were normally disulfide-bonded. A treatment that resulted in the maximal reduction of the disulfide bond also resulted in maximal loss of cell attachment activity. These results indicate that the 76-amino acid disulfide loop at the carboxyl terminus of invasin is required for recognition by integrins. 相似文献
49.
Synthesis,Pharmacological Evaluation,and Docking Studies of Novel Pyridazinone‐Based Cannabinoid Receptor Type 2 Ligands 下载免费PDF全文
Dr. Giulio Ragusa Dr. Serena Bencivenni Dr. Paula Morales Dr. Tyra Callaway Dr. Dow P. Hurst Dr. Battistina Asproni Dr. Stefania Merighi Dr. Giovanni Loriga Prof. Gerard A. Pinna Prof. Patricia H. Reggio Prof. Stefania Gessi Prof. Gabriele Murineddu 《ChemMedChem》2018,13(11):1102-1114
In recent years, cannabinoid type 2 receptors (CB2R) have emerged as promising therapeutic targets in a wide variety of diseases. Selective ligands of CB2R are devoid of the psychoactive effects typically observed for CB1R ligands. Based on our recent studies on a class of pyridazinone 4‐carboxamides, further structural modifications of the pyridazinone core were made to better investigate the structure–activity relationships for this promising scaffold with the aim to develop potent CB2R ligands. In binding assays, two of the new synthesized compounds [6‐(3,4‐dichlorophenyl)‐2‐(4‐fluorobenzyl)‐cis‐N‐(4‐methylcyclohexyl)‐3‐oxo‐2,3‐dihydropyridazine‐4‐carboxamide ( 2 ) and 6‐(4‐chloro‐3‐methylphenyl)‐cis‐N‐(4‐methylcyclohexyl)‐3‐oxo‐2‐pentyl‐2,3‐dihydropyridazine‐4‐carboxamide ( 22 )] showed high CB2R affinity, with Ki values of 2.1 and 1.6 nm , respectively. In addition, functional assays of these compounds and other new active related derivatives revealed their pharmacological profiles as CB2R inverse agonists. Compound 22 displayed the highest CB2R selectivity and potency, presenting a favorable in silico pharmacokinetic profile. Furthermore, a molecular modeling study revealed how 22 produces inverse agonism through blocking the movement of the toggle‐switch residue, W6.48. 相似文献
50.
A video database of moving faces and people 总被引:3,自引:0,他引:3
O'Toole AJ Harms J Snow SL Hurst DR Pappas MR Ayyad JH Abdi H 《IEEE transactions on pattern analysis and machine intelligence》2005,27(5):812-816
We describe a database of static images and video clips of human faces and people that is useful for testing algorithms for face and person recognition, head/eye tracking, and computer graphics modeling of natural human motions. For each person there are nine static "facial mug shots" and a series of video streams. The videos include a "moving facial mug shot," a facial speech clip, one or more dynamic facial expression clips, two gait videos, and a conversation video taken at a moderate distance from the camera. Complete data sets are available for 284 subjects and duplicate data sets, taken subsequent to the original set, are available for 229 subjects. 相似文献