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1.
  • 1.1. Goldfish (Carassius auratus) were fitted with ECG electrodes and intra-cranial stainless steel electrodes to monitor cardiac, EEG and SPS responses, during minimal restraint, to presentation of environmental stimuli (light-on, moving shadow, tap).
  • 2.2. All three stimuli evoked a bradycardia and increases in the EEG frequency; correlates of arousal responses in fish.
  • 3.3. EEG frequency changes were most evident in the fore- and midbrain regions; in the hindbrain smaller responses nevertheless showed discrimination between stimuli.
  • 4.4. EEG amplitude changes were more site- and stimulus-specific than frequency changes.
  • 5.5. SPSs occurred on stimulus presentations which were negative in polarity in the midbrain and positive in the forebrain and hindbrain, though the latter were smaller and less consistent.
  • 6.6. Principal components analyses and regression analyses were used to examine detailed associations between peripheral and central physiological changes.
  • 7.7. It was found that increases in the EEG frequency of fore- and midbrain regions were related to cardiac deceleration on early stimulus presentations.
  • 8.8. This was also shown for the negative SPS of the midbrain to the presentation of the tap stimulus.
  • 9.9. Positive SPSs of the forebrain were related to the bradycardia on later stimulus presentation i.e. during habituation of the arousal response.
  • 10.10. The results indicate that in fish, as in other vertebrates, negative SPSs in the midbrain are associated with arousal and implicate the forebrain in the modulation of arousal by its habituation.
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2.
This paper comments on: Low, B. S., Alexander, R. D., and Noonan, K.M. Human hips, breast, and buttocks: Is fat deceptive? Ethology and Sociobiology 8: 249-247, 1987. In it I argue that:
  • 1.1. Sexual selection has probably not been the most important selection pressure on
  • 2.female human body shape.
  • 3.2. Male humans in different cultures find different aspects of the female body attractive
  • 4.and therefore are unlikely to have exerted consistent directional sexual selection on
  • 5.the female body.
  • 6.3. Breast size is not correlated with lactation success.
  • 7.4. Visible hip width is not correlated with parturition success.
  • 8.5. Women would lower their fitness if they tried to deceive men about their internal
  • 9.pelvic dimensions.
  • 10.6. There are many alternative hypothesis to explain the existence of fat onwomen's
  • 11.breast, hips, and buttocks.
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3.
  • 1.1. The rate of oxygen consumption has been monitored continuously in M. edulis during acute exposure to high sublethal concentrations of formaldehyde, phenol and benzene and subsequent recovery periods of 96 hr.
  • 2.2. The results are discussed in relation to changes in the electrochemical potential difference of sodium, the content of ATP and the tissue concentration of strombine.
  • 3.3. After exposure to benzene and phenol, an increase in the rate of oxygen consumption that could not be explained by oxygen debt from the exposure period was observed.
  • 4.4. Depression of the rate of oxygen consumption after exposure to formaldehyde may be explained by a reduced ability to extract oxygen from the water.
  • 5.5. The pattern of oxygen consumption and behavioural responses, as well as the combined changes in the biochemical markers, were distinctly different in the three cases.
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4.
  • 1.1. The ECG of aquatic Amhystoma tigrinum from the Colorado Rocky Mountains was recorded while the animals submerged and emerged in water. Older larvae and metamorphosed adults were compared.
  • 2.2. Free-swimming animals of both types showed slight emergence tachycardia when taking a “gulp” of air.
  • 3.3. Preventing access to air for 30 min or more resulted in a slight bradycardia in larvae. Some adults responded with increased, others with decreased, heart rate depending on their level of excitement.
  • 4.4. Restraining the animals before forced submergence caused a greater bradycardia than when unrestrained.
  • 5.5. Low dissolved oxygen accentuated the cardiac responses of larvae to submergence but not in adults.
  • 6.6. Atropine only partially blocked the diving responses of both forms.
  • 7.7. The degree of submergence bradycardia seems to be a function of the ability to extract oxygen from water. It probably is not an adaptation to diving in these forms. Instead the submerged heart rate in these predominantly aquatic salamanders may be the “normal” rate with emergence tachycardias for breaths of air.
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5.
  • 1.1. A lipoxygenase preparation was obtained from Thermoactinomyces vulgaris and was purified by affinity chromatography on a linoleyl aminoethyl sepharose column.
  • 2.2. Two active fractions were obtained.
  • 3.3. The fraction obtained by elution with 100 mM borate buffer pH 9.0 was used in the subsequent work.
  • 4.4. Th. vulgaris lipoxygenase oxidized linoleic acid into two products: 13-HPOD and 9-HPOD at a ratio of 44 to 56, respectively.
  • 5.5. The identification and characterization of the isomers was done by HPLC, I.R. and mass spectrometry.
  • 6.6. When arachidonic acid was used as substrate, 15-HPETE and 15-HETE were found to be the main enzymatic products.
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6.
  • 1.1. A comparison was made of the mechanical performance of heart muscle from mouse, an atricial mammal, with corticosterone as glucocorticoid and spiny mouse (Acomys cahirinus), a precocial mammal, with cortisol as glucocorticoid.
  • 2.2. Force-frequency responses were negative in mouse and positive in spiny mouse.
  • 3.3. During recovery, there was a gradual increase and an overshoot in the mouse, while in the spiny mouse there was an initial enhanced response, diminishing gradually with time.
  • 4.4. High calcium concentration inhibited contractile tension in mouse heart, while it was positively inotropic in spiny mouse heart. Changes in the concentration of calcium did not change the patterns of force-frequency response.
  • 5.5. Lowering the experimental temperature increased the time course and amplitude of the tension curve. However, various parameters exhibited different temperature sensitivity.
  • 6.6. There was a significant difference in the levels of circulating cortisol between male and female spiny mice.
  • 7.7. It is proposed that the differences in the mechanical responses of mouse and spiny mouse hearts may be explained in terms of the effects of the specific glucocorticoid hormone on the development of the sodium-calcium exchanger.
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7.
  • 1.1. The effect of regular handling on fear reactions was investigated in mallard (Anas platyrhynchos) by exposing six hand-reared and four wild ducks to an approaching human being and recording heart rates with an external ECG device.
  • 2.2. All ducks reacted to the approach with tachycardia, but the response was significantly less in tame birds.
  • 3.3. Hand-reared females showed less response than males. No sex-linked differences were apparent in the wild ducks.
  • 4.4. Decreasing responses throughout the experiments were only found in tame birds.
  • 5.5. Fear or stress reactions can apparently be diminished through habituation induced by regular handling.
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8.
  • 1.1. Some aspects of the gas exchange system of a diving lizard, Physignathus lesuewii were studied.
  • 2.2. Breathing patterns were analysed.
  • 3.3. Breathing rate increases logarithmically with temperature and Q10 = 1.8. LogBR = −0.237 + 0.0256 T.
  • 4.4. Gas tensions in lung air and arterial and venous blood were measured. Arterial pH declines with increasing temperature.
  • 5.5. Temperature has a marked effect on oxygen affinity of the blood (ΔH = −10.1 kcal mol). A Bohr effect was also noted.
  • 6.6. CO2 equilibrium curves were drawn.
  • 7.7. The results are considered with a view to anticipating the efficiency of the gas exchange system of this species under conditions of variable temperature and during diving.
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9.
  • 1.1. Low concentrations (0.05−0.38 BU/ml) of a crude venom extract from P. triangulum F. potentiate nerve-evoked contractions of the locust hindgut, possibly due to contamination of the venom preparation with proctolin.
  • 2.2. Higher venom concentrations inhibit nerve-evoked contractions to a dose-independent plateau level.
  • 3.3. The venom has no effect on responses to bath-applied proctolin, but responses to bath-applied L-glutamate are inhibited.
  • 4.4. Spontaneous contractions are unaffected by the venom.
  • 5.5. It is concluded that the plateau contractions are the result of excitation by non-glutamatergic transmission, and are possibly the result of proctolin release.
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10.
  • 1.1. A variety of haematological parameters were determined in adult Dasyurus viverrinus.
  • 2.2. Haemoglobin and red cell counts were high with a very low mean cell volume.
  • 3.3. Basophils are absent but the eosinophils contain small numbers of basophilic granules which may indicate a dual role for this cell.
  • 4.4. “Ring Form” leucocytes are present.
  • 5.5. Three types of red cell picture could be identified, some animals showing large numbers of spherocytes, spicule cells, and inclusion bodies.
  • 6.6. These cells resemble those found in some inherited human haemolytic anaemias but there was no evidence of haemolysis in the animals.
  • 7.7. An alkali resistant haemoglobin component is present.
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11.
  • 1.1. Mortality was 100% at pH 3.5 over a temperature range of 10–30°C for embryos and nymphs of Caenis diminuta and C. hilaris.
  • 2.2. Hatching success for both species was highest at pH values above 4.5.
  • 3.3. Survival capacities were significantly higher at 20°C over a pH range of 4.0-7.2.
  • 4.4. Oxygen consumption rates increase as a function of increasing temperature and reduced acidity.
  • 5.5. Loss of the nymphal righting response was observed at pH 3.5. This response can be used as a behavioral assay for acid stress.
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12.
  • 1.1. Liver nuclei isolated from male mice treated with the carcinogen N,N-diethylnitrosamine were examined for the homopolymer poly(adenosine diphosphate ribose) and for the activity of the conjugate polymerase.
  • 2.2. At all levels of the carcinogen tested, a concomitant increase in both poly(adenosine diphosphate ribose) content and activity of the enzyme were found.
  • 3.3. Both responses were transitory and dose dependent.
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13.
  • 1.1. Changes in the blood and in the rate of oxygen consumption of Japanese eels injected intramuscularly in the head with a lethal dose of typical or atypical Aeromonas salmonicida at 20°C were investigated.
  • 2.2. Eels infected with the bacteria became moribund within 4 to 6 days, and then died within 1 day.
  • 3.3. The O2 consumption rate and blood parameters changed markedly with infections. The responses of hosts to infection by the two kinds of bacteria differed with regard to the following four points: blood pH, plasma Cl, lactic acid, and the numbers of granulocytes and lymphocytes.
  • 4.4. The responses of eels infected with atypical A. salmonicida were larger and more rapid than those of eels infected with typical A. salmonicida.
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14.
  • 1.1. Serum from the Pacific hagfish,Eptatretus stouti,contains a complement-like protein (CLP).
  • 2.2. CLP from unfractionated hagfish serum and from affinity-purified preparations binds to yeast cell surfaces.
  • 3.3. Incubation with CLP enhances the phagocytosis of yeast by hagfish leukocytes.
  • 4.4. CLP-mediated opsonization can be inhibited by anti-CLP antibody, EDTA, d(+)mannose and l(+)rhamnose.
  • 5.5. Additional opsomic factors are also in hagfish serum.
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15.
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Highlights
  • •Auxin responsive proteins in Arabidopsis roots were identified from 3,514 detected proteins.
  • •All six auxin receptors are stable in response to hormone via novel MRM assays.
  • •The >100 differentially expressed proteins exhibit dynamic and transient responses to auxin.
  • •Phenotypic screening of the top responsive proteins uncovered several novel root mutants.
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16.
  • 1.1. Morphological similarities and differences for the urticating apparatus of three Lepidoptera were studied using a scanning electron microscope.
  • 2.2. Complementary anatomical studies of the urticant apparatus were undertaken to explain the morphological results.
  • 3.3. Biochemical identity of a thaumetopoein-like protein (an urticating protein) was demonstrated for Thaumatopoea urticating hairs but not for Hylesia moth spicules.
  • 4.4. Urticating mechanisms appear to be different across species of Lepidoptera.
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17.
  • 1.1. An anatomical and physiological investigation was made of several components in the withdrawal escape response of the hermit crab, Pagurus pollicarus.
  • 2.2. In the fused last thoracic-first abdominal ganglion, the giant axon (GA) synapses with the giant motor (GM) neuron which innervates the abdominal flexor muscles.
  • 3.3. The synapse is unidirectional, conducting impulses only from the GA to the GM.
  • 4.4. The synaptic delay time is less than 0.4 msec.
  • 5.5. Concentrations of MgCl2 and MnCl2 which normally block chemical synapses were ineffective in interfering with GA-GM transmission.
  • 6.6. The GA-GM synapse was reversibly blocked by 0.5 mM DNP.
  • 7.7. It is concluded that GA-GM connection is a rectifying electrical synapse.
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18.
  • 1.1. Six different monoclonal IgG mouse antibodies to heparin lyase I from Flavobacterium heparinum were prepared.
  • 2.2. The monoclonal antibodies were used to detect heparin lyases I, II and III by dot-blotting immunoassay and by Western blotting.
  • 3.3. Individual antibodies showed different reactivity toward the three heparin lyases.
  • 4.4. The reactivity of two of the monoclonal antibodies was destroyed by exposing heparin lyases to sodium dodecyl sulfate.
  • 5.5. The antibodies can be used to rapidly distinguish between the three heparin lyases.
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19.
  • 1.1. A choriolytic enzyme was isolated from the hatching medium of the pike, Esox lucius.
  • 2.2. The enzyme is defined as hatching enzyme.
  • 3.3. The molecular weight of the enzyme is 24,000.
  • 4.4. The enzyme is a glycoprotein containing 2% carbohydrate.
  • 5.5. Its isoelectric point is 6.5.
  • 6.6. The pH optimum is around pH 8.
  • 7.7. The enzyme molecule contains two disulfide bonds but no free cysteine.
  • 8.8. Inhibitor studies and metal analysis show that the enzyme is a zinc-metalloprotease.
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20.
  • 1.1. Seven natural populations of Dacus dorsalis were analyzed for a dimeric esterase by means of horizontal starch-gel electrophoresis.
  • 2.2. The electrophoretic phenotypes were governed by nine codominant Est-D alleles.
  • 3.3. The commonest allele in all seven population samples was Est-D100 which encoded an electrophoretic band with intermediate mobility.
  • 4.4. The distribution of EST-D phenotypes were in accordance with Hardy-Weinberg expectations.
  • 5.5. There was no geographic variation in the distribution of Est-D alleles.
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