Subordinate Fish Mediate Aggressiveness Using Recent Contest Information

Memorizing dominance relationships can help animals avoid unwinnable subsequent contests. However, when competitive ability changes over time—for example, as a function of condition—it may be adaptive to “forget” these dominance relationships and for subordinates to once again enter contests with previously dominant individuals. Here, we examined the behavior of pairs of male cichlid fish, Julidochromis transcriptus, in repeated contests separated by different time intervals. We found that the time taken to reach resolution of dominance relationships influenced subsequent aggressive behavior of the subordinate toward the dominant, with longer initial contests leading to higher subsequent aggression. Longer time intervals between contests also increased aggression from the subordinate toward the dominant. These results are consistent with increasing uncertainty due to ambiguous contest outcomes and increasing time intervals. Our results also show that a longer time was necessary to resolve contests between larger pairs, suggesting a self-assessment strategy, but not a mutual assessment strategy. Taken together, larger individuals appear to adaptively lose or ignore previously gathered social information because they have a higher fighting ability and better body condition. Therefore, we conclude that losing or ignoring unreliable information may be an adaptive strategy in the context of dominance relationships.

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Effect of Erythropoietin Treatment on Nutritional Status of Continuous Ambulatory Peritoneal Dialysis Patients

Peritoneal Dialysis International ◽

10.1177/089686089301302s133 ◽

1993 ◽

Vol 13 (2_suppl) ◽

pp. 544-549 ◽

Cited By ~ 5

Author(s):

Elias V. Balaskas ◽

I. Rogers Melamed ◽

Amit Gupta ◽

Joanne Bargman ◽

Dimitrios G. Oreopoulos

Keyword(s):

Nutritional Status ◽

Serum Albumin ◽

Absolute Lymphocyte Count ◽

Well Being ◽

Underlying Disease ◽

Phosphate Binders ◽

Self Assessment ◽

Erythropoietin Treatment ◽

Changes Over Time ◽

Over Time

Seventeen patients -10 females, 7 males -mean age 52 years (range: 21–77 years), on CAPD for an average of 35 months (range 10–160 months) were studied. Mean initial dose of EPO was 114±45 U/kg/week subcutaneously (range: 59–209). The dose was adjusted to achieve and maintain a target Hb of 100 g/L and Hct 30%. Fifteen of the patients (88.2%) achieved this target within 6 months [baseline to month 6 changes: Hb 72±10 g/L to 107±12 g/L (p=0.0001); Hct 22±3% to 33±4% (p=0.0001)]. Serum total protein also increased significantly over the time of EPO use (p=0.0133); changes from baseline were significant by the fourth month [68±9 g/L to 72±9 g/L (p=0.0115)]. Serum albumin also increased significantly over time (p=0.0157). The change from the baseline result (37±4 g/L) was statistically significant by month 2 (p=0.0060) and was maintained over the following 4 months [month 6 result: 40±3 g/L (p=0.0180)]. The increase was greater for 8 patients with initial serum albumin <35 g/L (mean change 5.75 g/L) than for the 9 subjects with levels >35 g/L (mean change 0.11 g/L). In a comparison group of 17 patients (matched for age, sex, duration of CAPD, underlying disease and antihypertensive treatment), who did not receive EPO treatment, albumin and protein did not appear to increase over time. Mean body weight increased from 60.9± 14.0 kg at the start to 62.1± 13.9 kg at month 6 (p=0.281) and the absolute lymphocyte count from 1.6±0.8 x 109/L to 1.8±1.0 x 109/L (p=0.0472). Serum potassium, urea, creatinine, phosphorus, cholesterol, tri. glycerides, WBC and platelets did not show significant changes over time. Serum phosphorus increased at the end of the second and third months (from 1.6±0.5 mmol/L to 1.9±0.4 and 1.8±0.4 mmol/L and then decreased at the sixth month (1.7±0.5 mmol/L); this is probably due to an increase in phosphate binders in 9 of 17 patients. An improvement in appetite, sleep and well-being, by patients’ self-assessment, was noted during the treatment. We conclude that the treatment with EPO is associated with improvement of the nutritional status of patients on CAPD.

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Hubungan Perilaku Perdagangan Investor Dengan Volume Perdagangan Di Bursa Efek Indonesia

Jurnal Manajemen Teori dan Terapan | Journal of Theory and Applied Management ◽

10.20473/jmtt.v2i1.2377 ◽

2009 ◽

Vol 2 (1) ◽

Author(s):

Ghazali Syamni

Keyword(s):

Trading Volume ◽

Stock Exchange ◽

Time Interval ◽

Time Intervals ◽

Using Data ◽

Changes Over Time ◽

Relationship Of ◽

The Relationship ◽

Order Pattern ◽

Over Time

This paper examines the relationship of behavior trading investor using data detailed transaction history-corporate edition demand and order history in Indonesia Stock Exchange during period of March, April and May 2005. Peculiarly, behavior placing of investor order at trading volume. The result of this paper indicates that trading volume order pattern to have pattern U shape. The pattern happened that investors have strong desires to places order at the opening and close of compared to in trading periods. While the largest orders are of market at the opening indicates that investor is more conservatively when opening, where many orders when opening has not happened transaction to match. In placing order both of investor does similar strategy. By definition, informed investors’ orders more large than uninformed investors. If comparison of order examined hence both investors behavior relatively changes over time. But, statistically shows there is not ratio significant. This implies behavior trading of informed investors and uninformed investors stable relative over time. The result from regression analysis indicates that informed investors to correlate at trading volume in all time intervals, but not all uninformed investors correlates in every time interval. This imply investor order inform is more can explain trading volume pattern compared to uninformed investor order in Indonesia Stock Exchange. Finally, result of regression also finds that order status match has greater role determines trading volume pattern intraday especially informed buy match and informed sale match. While amend, open and withdraw unable to have role to determine intraday trading volume pattern.

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Two's Company, Three's a Crowd: Differences in Dominance Relationships in Isolated Versus Socially Embedded Pairs of Fish

Behaviour ◽

10.1163/156853903771980558 ◽

2003 ◽

Vol 140 (10) ◽

pp. 1193-1217 ◽

Cited By ~ 38

Author(s):

Peter Murch ◽

Craig Tovey ◽

Ivan Chase

Keyword(s):

Social Context ◽

Cichlid Fish ◽

Dominance Behavior ◽

Dyadic Interactions ◽

Theoretical Approaches ◽

Dominance Relationships ◽

The Social ◽

Game Theoretic ◽

The Stability ◽

Over Time

AbstractWe performed experiments with cichlid fish to test whether several basic aspects of dominance were the same in isolated pairs as in pairs within a social group of three or four. We found that the social context, whether a pair was isolated or within a group, strongly affected the basic properties of dominance relationships. In particular, the stability of relationships over time, the replication of relationships in successive meetings, and the extent of the loser effect were all significantly less in socially embedded pairs than in isolated pairs. We found no significant winner effect in either isolated or socially embedded pairs. These findings call into question many current approaches to dominance that do not consider social context as an important factor in dominance behavior. These findings also cast serious doubt on the validity of empirical and theoretical approaches based on dyadic interactions. Among these approaches are game theoretic models for the evolution of aggressive behavior, experimental designs evaluating how asymmetries in attributes influence the outcome of dominance

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Wind Variability as a Function of Time at Muroc, California

Bulletin of the American Meteorological Society ◽

10.1175/1520-0477-37.5.207 ◽

1956 ◽

Vol 37 (5) ◽

pp. 207-210

Author(s):

Bernard M. Singer

Keyword(s):

Time Variability ◽

Time Interval ◽

Time Intervals ◽

Velocity Change ◽

Wind Variability ◽

Changes Over Time ◽

Vector Wind ◽

Over Time ◽

Horizontal Vector ◽

Height Interval

Records of 226 sets of triple theodolite balloon observations taken at Muroc, California, to heights of 38,000 feet have been analyzed to determined magnitudes of horizontal vector wind changes over time intervals from thirty minutes to five hours. The medians of magnitudes of velocity change vary from 2.0 mph over a time interval of 30 minutes to 6.4 mph over a time interval of five hours. The effect of altitude upon time variability of these winds has been studied. The height interval from the surface to 38,000 feet was separated into four altitude zones and it was found that wind variability is greater near the surface than in the zone above it. From the second zone upward, wind variability increased with height.

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Self-Assessment of Reaction Thresholds in Food Allergy: A New Theory of Risk Taking which Changes Over Time

Journal of Allergy and Clinical Immunology ◽

10.1016/j.jaci.2008.12.529 ◽

2009 ◽

Vol 123 (2) ◽

pp. S142-S142 ◽

Cited By ~ 3

Author(s):

A. DunnGalvin ◽

J.O.B. Hourihane

Keyword(s):

Food Allergy ◽

Risk Taking ◽

Self Assessment ◽

Reaction Thresholds ◽

Changes Over Time ◽

Over Time

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Comparison of two devices for measuring exercise transcutaneous oxygen pressures in patients with claudication

VASA ◽

10.1024/0301-1526/a000454 ◽

2015 ◽

Vol 44 (5) ◽

pp. 355-362 ◽

Cited By ~ 8

Author(s):

Marie Urban ◽

Alban Fouasson-Chailloux ◽

Isabelle Signolet ◽

Christophe Colas Ribas ◽

Mathieu Feuilloy ◽

...

Keyword(s):

Oxygen Pressure ◽

Optical Sensors ◽

Chemical Sensors ◽

Transcutaneous Oxygen ◽

Starting Values ◽

Two Systems ◽

Transcutaneous Oxygen Pressure ◽

New Sensors ◽

Changes Over Time ◽

Over Time

Abstract. Summary: Background: We aimed at estimating the agreement between the Medicap® (photo-optical) and Radiometer® (electro-chemical) sensors during exercise transcutaneous oxygen pressure (tcpO2) tests. Our hypothesis was that although absolute starting values (tcpO2rest: mean over 2 minutes) might be different, tcpO2-changes over time and the minimal value of the decrease from rest of oxygen pressure (DROPmin) results at exercise shall be concordant between the two systems. Patients and methods: Forty seven patients with arterial claudication (65 + / - 7 years) performed a treadmill test with 5 probes each of the electro-chemical and photo-optical devices simultaneously, one of each system on the chest, on each buttock and on each calf. Results: Seventeen Medicap® probes disconnected during the tests. tcpO2rest and DROPmin values were higher with Medicap® than with Radiometer®, by 13.7 + / - 17.1 mm Hg and 3.4 + / - 11.7 mm Hg, respectively. Despite the differences in absolute starting values, changes over time were similar between the two systems. The concordance between the two systems was approximately 70 % for classification of test results from DROPmin. Conclusions: Photo-optical sensors are promising alternatives to electro-chemical sensors for exercise oximetry, provided that miniaturisation and weight reduction of the new sensors are possible.

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