Active Beings Research Articles

The concept of ‘IT artifact’ has outlived its usefulness and should be retired now

AbstractVastly inconsistent definitions of the term “the IT artifact” in leading journals and conferences demonstrate why it no longer means anything in particular and should be retired from the active IS lexicon. Examples from the literature show why artifact‐cousins, such as the IS artifact, sociotechnical artifact, social artifact, and ensemble artifact should be used with great care, if not retired as well. Any void created by these retirements could be filled through the following approaches: (i) relabeling with simple terms that are immediately understandable; (ii) adopting guidelines for making sense of the whole X‐artifact family; and (iii) sidestepping the IT artifact and focusing directly on IT‐enabled work systems in organizations.

Site-Specific RNase A Activity Was Dramatically Reduced in Serum from Multiple Types of Cancer Patients

Potent RNase activities were found in the serum of mammals but the physiological function of the RNases was never well illustrated, largely due to the caveats in methods of RNase activity measurement. None of the existing methods can distinguish between RNases with different target specificities. A systematic study was recently carried out in our lab to investigate the site-specificity of serum RNases on double-stranded RNA substrates, and found that serum RNases cleave double-stranded RNAs predominantly at 5′-U/A-3′ and 5′-C/A-3′ dinucleotide sites, in a manner closely resembling RNase A. Based on this finding, a FRET assay was developed in the current study to measure this site-specific serum RNase activity in human samples using a double stranded RNA substrate. We demonstrated that the method has a dynamic range of 10−5 mg/ml- 10−1 mg/ml using serial dilution of RNase A. The sera of 303 cancer patients were subjected to comparison with 128 healthy controls, and it was found that serum RNase activities visualized with this site-specific double stranded probe were found to be significantly reduced in patients with gastric cancer, liver cancer, pancreatic cancer, esophageal cancer, ovary cancer, cervical cancer, bladder cancer, kidney cancer and lung cancer, while only minor changes were found in breast and colon cancer patients. This is the first report using double stranded RNA as probe to quantify site-specific activities of RNase A in a serum. The results illustrated that RNase A might be further evaluated to determine if it can serve as a new class of biomarkers for certain cancer types.

LIFE IS A JOURNEY

The debate between narrativists and ludologists has long enlivened discussions among game theorists. Should videogames be seen as an offshoot of (film) stories, and thus be studied primarily from the perspective of narratology? Or do they represent a truly different phenomenon, and thus require an analytic approach that has nothing to gain from narratology? In this paper we intend not so much to solve this conundrum as suggest how it has arisen in the first place, by showing what journey stories and videogames that involve the movement of the player’s avatar have in common. Our central claim is that both journey stories and such games involve physical movement and quests, and moreover are based on some sort of ‘story’, but that only the stories allow for rich mappings of the conceptual metaphor PURPOSIVE ACTIVITY IS MOVEMENT TOWARD A DESTINATION. If our explanations make sense, they can contribute both to the classification and theorization of videogames and to the expansion of conceptual metaphor theory into the realm of videogames.

Detection of a novel active transposable element in Caldicellulosiruptor hydrothermalis and a new search for elements in this genus

We show that a previously annotated hypothetical protein is the transposase of a new and active IS element, ISCahy1, widespread in Caldicellulosiruptor species. Transposition generated an 11-bp direct repeat at the insertion site in Caldicellulosiruptor hydrothermalis, suggesting a cut-and-paste mechanism. The discovery of an active insertion sequence in Caldicellulosiruptor species led to a survey of potential IS elements in the genome sequences of eight Caldicellulosiruptor species that identified several new elements, including one novel to this genus.

Biological activity analysis of native and recombinant streptokinase using clot lysis and chromogenic substrate assay.

DETERMINATION OF STREPTOKINASE ACTIVITY IS USUALLY ACCOMPLISHED THROUGH TWO ASSAY METHODS: a) Clot lysis, b) Chromogenic substrate assay. In this study the biological activity of two streptokinase products, namely Streptase®, which is a native product and Heberkinasa®, which is a recombinant product, was determined against the third international reference standard using the two forementioned assay methods. The results indicated that whilst the activity of Streptase® was found to be 101 ± 4% and 97 ± 5% of the label claim with Clot lysis and Chromogenic substrate assay respectively, for Heberkinasa® the potency values obtained were 42 ± 5% and 92.5 ± 2% of the label claim respectively. To shed some light on the reason for this finding, the n-terminal sequence of the streptokinase molecules present in the two products was determined. The results showed slight differences in the amino acid sequence of the recombinant product in comparison to the native one at the amino terminus. This finding supports those of other workers who found that n-terminal sequence of the streptokinase molecule can have significant effect on the activity of this protein.

SERUM PYRROLIDONE CARBOXYPEPTIDASE ACTIVITY IS MODIFIED IN POSTMENOPAUSAL BUT NOT PREMENOPAUSAL WOMEN WITH BREAST CANCER

189 Citation: Maturitas Volume 63, Supplement 1, May 2009, Page S51 SERUM PYRROLIDONE CARBOXYPEPTIDASE ACTIVITY IS MODIFIED IN POSTMENOPAUSAL BUT NOT PREMENOPAUSAL WOMEN WITH BREAST CANCER M.J. Ramirez-Exposito, M.P. Carrera-Gonzalez, B. Duenas, J.M. Martinez-Martos 1 University of Jaen, Jaen, Spain; University of Jaen, Health Sciences, Jaen, Spain; Complejo Hospitalario de Jaen, Jaen, Spain Objectives: Pyrrolidone carboxypeptidase (Pcp) (E.C. 3.4.19.3), is an omega peptidase widely distributed in fluids and tissues and hydrolyses N-terminal pyroglutamic residues from biologically active peptides such as gonadotropin releasing hormone (GnRH). Previous results obtained by us showed a decrease in human breast cancer tissue Pcp activity, suggesting that this enzyme activity or its putative substrates may play a major role in breast cancer pathogenesis. The aim of the present work is to analyse serum Pcp activity in preand postmenopausal women with breast cancer and to compare it with their respective controls. Methods: We measured fluorometrically serum Pcp activity using pyroglutamyl-beta-naphthylamide as substrate in 57 women diagnosed with ductal infiltrating carcinomas. Results: Healthy postmenopausal women showed higher values of Pcp activity than premenopausal women (98.69±4.94.vs 79.06±4.37 pmol/min/mg protein). On the contrary, no differences were found in serum Pcp activity between preand postmenopausal women with breast cancer (75.62±4.42 vs 79.71±4.63 pmol/min/mg protein). Conclusions: The present results document changes in Pcp activity in serum of postmenopausal but not premenopausal women with breast cancer. These changes may reflect the functional status of the enzyme substrates, which can be selectively activated or inhibited as a result of specific conditions brought about by the tumor under different hormonal conditions. In this connection, GnRH receptors and GnRH mRNA have been found in breast tissue, raising the possibility of a local role for GnRH in the human mammary gland.

Intraspecific variation in foraging behaviour: influence of shore height on temporal organization of activity in the chiton Acanthopleura japonica

The chiton Acanthopleura japonica has a wide vertical distribution on moderately exposed Hong Kong shores, and it shows limited seasonal vertical migration. Observations revealed that chitons were active while awash on ebbing or flooding tides during both day- and night-time, but they were inactive in refuges at their resting shore heights when conditions were unfavourable. The most intense activity was always associated with awash periods, but the timing of activity peaks and percentage activity varied between seasons, tidal conditions and the shore height individuals'occupied. Activity periods were longer in summer than winter, but varied from day to day, depending on weather conditions such as wind speed and hours of sunshine. Duration of activity also varied with shore height; chitons living in the high-shore remaining active for nearly twice as long as those lower on the shore. Laboratory studies showed that activity Was controlled by a circalunidian endogenous rhythm, but can be overridden by exogenous, environmental factors, such as wave splash. Therefore, the temporal organization of activity in A. japonica is controlled by both exogenous and endogenous mechanisms, of which the timing and duration of the awash phase of the tide appears to be the dominant controlling factor. To optimize foraging success, individuals exhibit a continuum of foraging strategies determined by season and the shore height they occupy, resulting in intraspecific variability in the duration and timing of activity.

Effects of postharvest sulphur fumigation, steam and low pH treatments on polyphenol oxidase activity in litchi (Litchi chinensis Sonn.) fruit

The effects of postharvest sulphur fumigation (0.6 kg elemental sulphur. 1000 kg−1 of fruit), steam (95°C) for two seconds, or steam (95°C) for two seconds followed by subsequent immersion in a zero pH solution for four minutes, on polyphenol oxidase activity in litchi (Litchi chinensis Sonn.) fruit were determined at harvest, and at successive daily intervals until five days after harvest, during which period the fruit were stored at 28°C. On the day of harvest, polyphenol oxidase activity Was highest in sulphur-fumigated fruit (605 units. g−1 fresh mass) but four days after harvest was highest in control fruit (ca 730 units. g−1 fresh mass). In contrast, polyphenol oxidase activity was significantly lower in fruit treated with steam (95°C) for two seconds (215 units. g−1 fresh mass), but was lowest in fruit treated with steam (95°C) for two seconds followed subsequent immersion in a zero pH solution for four minutes (ca 50 units. g−1 fresh mass). Consequently, steam (95°C) and low pH both decreased polyphenol oxidase activity and the effect was additive.

CUSTOM PRODUCERS END DIFFICULT YEAR

THE PACE OF ACTIVITY WAS frenetic at the 15th annual CPhI Worldwide trade show in Brussels last week. Producers of fine and custom chemicals were cautiously optimistic that changes within the industry might start yielding positive results next year, after a difficult 2004. Many industry players, including those working in niche areas, said they are pleased with the level of customer interest they are seeing. Some, especially the larger companies, are hoping that their recent restructurings will better position their businesses. Success also seems to depend on where companies target their activities. Sigma-Aldrich, which officially launched its new fine chemicals business SAFC at the meeting, said its spring acquisition of Ultrafine has given it a full range of capabilities to support customers from the preclinical stage through clinical development to commercialization. The move has contributed in part to a doubling of inquiries over the past six months, said Ed Roullard, director of ...

Monastery or Economic Enterprise: Opposing or Complementary Metaphors of Higher Education?

Two opposing metaphors of higher education are identified and discussed. The first, "KNOWLEDGE IS AN ECONOMIC GOOD" and "ACADEMIC ACTIVITY IS ECONOMIC PRODUCTION," appeals to business leaders, politicians, and career-minded students. The second, "UNIVERSITY AS MONASTIC COMMUNITY," related to the "UNIVERSITY AS COMMUNITY" metaphor discussed by Batstone (2000), can be identified with the medieval origins of the university and appeals to tradition-minded academicians, especially in the humanities and social sciences. Drawing on Vervaeke and Kennedy's (1996) critique of the concept of unique implicit metaphors, I argue that each metaphor illuminates unique aspects of the target concept: higher education. In the case of contradictory metaphors for a complex concept such as higher education, I argue that the solution is neither to reject one root metaphor in favor of the other nor to attempt some form of synthesis but to regard each as a limited and partial expression of the concept in its entirety.

Multiuser Detection for Out-of-Cell Cochannel Interference Mitigation in the IS–95 Downlink

This paper considers the application of multiuser detection techniques to improve the quality of downlink reception in a multi-cell IS---95 digital cellular communication system. In order to understand the relative performance of suboptimum multiuser detectors including the matched filter detector, optimum multiuser detection in the context of the IS---95 downlink is first considered. A reduced complexity optimum detector that takes advantage of the structural properties of the IS---95 downlink and exhibits exponentially lower complexity than the brute-force optimum detector is developed. The Group Parallel Interference Cancellation (GPIC) detector, a suboptimum, low-complexity multiuser detector that also exploits the structure of the IS---95 downlink is then developed. Simulation evidence is presented that suggests that the performance of the GPIC detector may be near-optimum in several cases. The GPIC detector is also tested on a snapshot of on-air data measured with an omnidirectional antenna in an active IS---95 system and is shown to be effective for extracting weak downlink transmissions from strong out-of-cell cochannel interference. The results of this paper suggest that the GPIC detector offers the most performance gain in scenarios where weak downlink signals are corrupted by strong out-of-cell cochannel interference.

Primer Premier 5

Primer Premier 5

Characterization of the Yeast Cdc7p/Dbf4p Complex Purified from Insect Cells: ITS PROTEIN KINASE ACTIVITY IS REGULATED BY Rad53p

The yeast Saccharomyces cerevisiae Cdc7p/Dbf4p protein kinase complex was purified to near homogeneity from insect cells. The complex efficiently phosphorylated yeast Mcm2p and less efficiently the remaining Mcm proteins or other replication proteins. Significantly, when pretreated with alkaline phosphatase, Mcm2p became completely inactive as a substrate, suggesting that it must be phosphorylated by other protein kinase(s) to be a substrate for the Cdc7p/Dbf4p complex. Mutant Cdc7p/Dbf4p complexes containing either Cdc7-1p or Dbf4-1 approximately 5p were also partially purified from insect cells and characterized in vitro. Furthermore, the autonomously replicating sequence binding activity of various dbf4 mutants was also analyzed. These studies suggest that the autonomously replicating sequence-binding and Cdc7p protein kinase activation domains of Dbf4p collaborate to form an active Cdc7p/Dbf4p complex and function during S phase in S. cerevisiae. It is shown that Rad53p phosphorylates the Cdc7p/Dbf4p complex in vitro and that this phosphorylation greatly inhibits the kinase activity of Cdc7p/Dbf4p. This result suggests that Rad53p controls the initiation of chromosomal DNA replication by regulating the protein kinase activity associated with the Cdc7p/Dbf4p complex.

The Biotransformation of Propylene to Propylene Oxide by Methylococcus Capsulatus (Bath): 2. A Study of the Biocatalyst Stability

Methylococcus capsulatus (Bath) possesses methane monooxygenase (MMO) which catalyses the epoxidation of propylene to propylene oxide. MMO activity could be maintained in whole cells by storage in unagitated vessels for several days. However if these cells were agitated and aerated in the absence of a carbon and energy source then 80% of the propylene-oxidizing activity Was lost within 24 h. It was shown that this loss of activity was due to the inability of the cells to provide energy to drive the oxidation process rather than the loss of MMO activity per se. If propylene oxide was added to these aerated cells then the rate of inactivation was increased and 50% of the activity was lost over a 10 min period. The addition of an exogenous energy source caused a doubling in the rate of inactivation. These marked increases in the rates of inactivation in the presence of propylene oxide were found to be caused by the loss of the methane monooxygenase activity per se rather than a further loss of the energy-producing systems. Cells actively producing propylene oxide from propylene, using methanol as an energy source, also lost their propylene oxide-producing capacity rapidly due to loss of the methane monooxygenase activity. The rate of inactivation under these circumstances was related to the rate of propylene oxide production from propylene rather than the level of this product in the culture supernatant.

Evidence for a role of translational frameshifting in the expression of transposition activity of the bacterial insertion element IS 1

The bacterial insertion element IS 1 contains two essential open reading frames, insA and insB, arranged in tandem. We have introduced a number of site-specific mutations into the region including the 3′-terminal region of insA, the region between insA and insB, and the ATG codon at the start of insB. Relative transposition activities of mutant and wild-type elements were determined using a modified in vivo cointegration assay. The results support the hypothesis that a translational (−1) frameshift occuring in the 3′-terminal region of insA and linking insB to insA is responsible for the synthesis of the active IS 1 transposition enzyme. Further results with IS 1 elements containing internal deletions are in agreement with a role of the normally terminated insA product as an inhibitor of transposition.

Acute and sustained effects of isosorbide 5-mononitrate in stable angina pectoris

Isosorbide 5-mononitrate (IS 5-MN) is an active metabolite of isosorbide dinitrate and is widely used as an antianginal agent. The acute and subacute (2 weeks) effects of IS 5-MN, 40 mg twice daily, were evaluated in 18 patients with stable angina pectoris using computerized exercise testing and a placebocontrolled, double-blind, randomized trial protocol. There were 2 phases of 2 weeks each in which patients received placebo or active IS 5-MN. Acute testing (8 patients) was performed 2 hours after the first dose and subacute testing 2 hours after the morning dose on day 14. Acute testing showed an increase in exercise time from a mean (± standard error of mean) of 8.2 ± 0.6 minutes to 11.1 ± 0.5 minutes (p < 0.001) after a single dose of IS 5-MN. Time to 1 mm of ST depression increased significantly and peak exercise ST-segment depression decreased significantly. Rest and peak exercise heart rate increased significantly during acute testing with IS 5-MN; blood pressure did not change significantly. After 2 weeks of therapy, exercise time had not changed (9.9 ± 0.6 with placebo to 9.7 ± 0.6 minutes). The beneficial effects on ST-segment variables were sustained at 2 weeks. The data suggest that there is an attenuation of effect with respect to exercise time and sustained beneficial effect on the ST-segment variables. This may be a result of development of partial tolerance to IS 5-MN after 2 weeks of therapy.

Comparative effect of phenobarbital and 3-methyl-cholanthrene on azodye metabolism in rat liver I. In vitro studies on detoxication and activation processes

The effect of phenobarbital (PB) and 3-methylcholanthrene (3-MC) administration on detoxication and activation of the carcinogenic azodye 4-dimethyl-aminoazobenzene (DAB) was studies in rat liver microsomes. Azoreductase activity and in vitro DAB metabolite binding to calf thymus DNA and microsomal protein were simultaneously determined. Pretreatment of rats with 3 daily injections of PB (80 mg/kg) did not significantly modify azoreductase activity by increased DAB metabolite binding to DNA (+ 67%) and to protein (+ 123%). The effect of 3-MC differed according to the route of administration. When it was given intraperitoneally (1 times 20 mg/kg)azoreductase was not modified and DAB metabolite binding to DNA and to protein was eight-fold enhance. After continuous administration of 3-MC in the diet (3.0 MG/KG/DAY)AZOREDUCTASE ACTIVITY WAS DECREASED (MINUS 40%), DAB metabolite binding to DNA was unchanged and DAB metabolite binding to protein tripled. Thus the balance between the formation of DAB metabolites bound to DNA and azoreduction led to an increased activation/reduction ratio only by 3-MC injection. In every case, the formation of DAB metabolites bound to protein was significantly increased as compared with detoxication. Different effects of PB and 3-MC were discussed with reference to the synthesis of distinct cytochromes.

Lubrication at the Second International CONGRESS OF SURFACE ACTIVITY

The EXTENT TO WHICH SURFACE ACTIVITY IS important in lubrication has been assessed differently at various times by research workers. At one time the “oiliness” of a lubricant was attributed by physical chemists to the adsorption of polar molecules on the surfaces undergoing lubrication. Recent workers have tended to discount the importance of such physical adsorption and to stress the existence of chemical reactions which lead to products having a beneficial effect and to which lubrication activity is attributable. It is therefore of some interest to consider what is the present viewpoint, taking as a source of information the series of extremely interesting papers presented in London during the week beginning on the 8th April, 1957.